BSRR

EX-99.1

2 bsrr-20260727xex99d1.htm

EX-99.1

Exhibit 99.1

FOR IMMEDIATE RELEASE

​

​

Date:

July 27, 2026

Contact:

Kevin McPhaill, President/CEO

Phone:

(559) 782-4900 or (888) 454-BANK

Website Address:

www.sierrabancorp.com

​

​

SIERRA BANCORP REPORTS FINANCIAL RESULTS FOR SECOND QUARTER AND FIRST SIX MONTHS OF 2026

Porterville, Calif. – (BUSINESS WIRE) – Sierra Bancorp (Nasdaq: BSRR), parent of Bank of the Sierra, today announced its unaudited financial results for the three- and six-month periods ended June 30, 2026. Sierra Bancorp reported consolidated net income of $9.9 million, or $0.77 per diluted share, for the second quarter of 2026, compared to $10.6 million, or $0.78 per diluted share, in the second quarter of 2025. Return on average assets was 1.09% and return on average equity was 10.90% for the second quarter of 2026.

For the first six months of 2026, the Company recognized net income of $22.4 million, or $1.72 per diluted share, as compared to $19.7 million, or $1.43 per diluted share, for the same period in 2025. The Company's improved financial performance metrics for the first half of 2026 include a net interest margin of 3.75% and an efficiency ratio of 57.70%, as compared to a net interest margin of 3.71% and efficiency ratio of 60.00% for the same period in 2025.

Highlights for the second quarter and first half of 2026:

●Strong YTD Earnings and Profitability (first half compared to same period last year)

oDiluted earnings per share increased by $0.29, or 20%, to $1.72 per diluted share.

oReturn on average assets rose to 1.24%, as compared to 1.09%.

oReturn on average equity expanded to 12.38%, as compared to 11.26%.

oNet interest margin remained strong at 3.75%, increasing four basis points from 3.71%.

oEfficiency ratio(1) improved to 57.70%, as compared to 60.00%.

​

●Deposit Franchise Strength and Low Cost of Funds

oTotal deposits increased $54.6 million, or 2%, from December 31, 2025.

oNoninterest-bearing deposits of $1.03 billion at June 30, 2026, represent 35.0% of total deposits.

oCost of total deposits declined to 1.11% compared to 1.30% in the second quarter of 2025, while cost of funds decreased to 1.31% from 1.49%.

oCore non-maturity deposits increased $67.8 million, or 3%, from December 31, 2025.

oUninsured deposits, exclusive of public funds, are approximately 25% of total deposit balances.

​

●Solid Capital and Liquidity

oTangible book value(1) per share increased to $26.19 at June 30, 2026, compared to $23.42 at December 31, 2025.

oRepurchased 396,429 shares of stock during the first half of 2026.

oDeclared dividend of $0.27 per share, payable on August 10, 2026.

oStrong regulatory Community Bank Leverage Ratio of 12.25%, at June 30, 2026, for our subsidiary Bank.

oTangible common equity ratio(1) of 9.19%, at June 30, 2026, on a consolidated basis.

oOverall primary and secondary liquidity sources of $1.9 billion at June 30, 2026.

(1)See reconciliation of non-GAAP financial measures to the corresponding GAAP measurement in "Non-GAAP Financial Measures."

Sierra Bancorp Financial Results

July 27, 2026

Page 2

​

“Coming together is the beginning. Keeping together is progress. Working together is success.”  – Henry Ford

​

“We are proud to serve the Central Valley and Central Coast of California. Our strong commitment to these communities is reflected in our continued solid deposit growth during 2026,” stated Kevin McPhaill, CEO and President. “I am particularly proud of our ability to pivot, as demonstrated by the surge in loan growth in the last couple of months. This shift reflects the team’s laser focus on both loan and deposit growth. In particular, our loan pipeline increased significantly, and we expect this momentum to result in net loan growth in the second half of 2026. Our expense management strategies resulted in a nearly 2% cost reduction in year-to-date expenses compared to the same period last year. We closed the quarter with contagious optimism throughout our Bank, boosting my confidence in what we can accomplish in the next six months and beyond!” concluded Mr. McPhaill.

Quarterly Income Changes (comparisons to the second quarter of 2025)

●Net income for the second quarter of 2026 decreased $0.7 million, or 7%, to $9.9 million. Net interest income remained stable, decreasing $0.2 million, while noninterest income increased slightly and noninterest expense decreased by $0.3 million. Noninterest expense in the second quarter of 2026 included approximately $0.5 million of severance and recruitment related charges resulting from a restructuring of the executive team. These changes were offset by a $1.1 million increase in credit loss expense on loans, resulting primarily from a $2.5 million specific reserve on a single agricultural production loan to a borrower in the lumber industry.

●Noninterest income and noninterest expense changes included a $0.4 million increase in earnings from separate

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SIERRA BANCORP_February 2, 2026 0001130144false00011301442026-02-022026-02-02 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) February 2, 2026

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On February 2, 2026, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the quarter and year ended December 31, 2025. A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No. ​ ​ ​ Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated February 2, 2026

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: February 2, 2026

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

SIERRA BANCORP_October 27, 2025 0001130144false00011301442025-10-272025-10-27 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) October 27, 2025

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On October 27, 2025, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and nine-month periods ended September 30, 2025.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated October 27, 2025

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: October 27, 2025

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

0001130144false00011301442025-07-282025-07-28 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) July 28, 2025

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices)             (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On July 28, 2025, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and six-month periods ended June 30, 2025.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

19

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated July 28, 2025

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: July 28, 2025

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​

0001130144false00011301442025-04-282025-04-28 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) April 28, 2025

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On April 28, 2025, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three-month period ended March 31, 2025.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

19

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated April 28, 2025

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: April 28, 2025

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​

0001130144false00011301442025-01-272025-01-27 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) January 27, 2025

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On January 27, 2025, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the quarter and year ended December 31, 2024. A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated January 27, 2025

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: January 27, 2025

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

0001130144false00011301442024-10-212024-10-21 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) October 21, 2024

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On October 21, 2024, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and nine-month periods ended September 30, 2024.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated October 21, 2024

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: October 21, 2024

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

0001130144false00011301442024-07-222024-07-22 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) July 22, 2024

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices)             (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On July 22, 2024, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and six-month periods ended June 30, 2024.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

19

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated July 22, 2024

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: July 22, 2024

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​

0001130144false00011301442024-04-222024-04-22 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) April 22, 2024

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On April 22, 2024, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three-month period ended March 31, 2024.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

19

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated April 22, 2024

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: April 22, 2024

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​

0001130144false00011301442024-01-292024-01-29 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) January 29, 2024

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On January 29, 2024, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the quarter and year ended December 31, 2023. A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated January 29, 2024

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: January 29, 2024

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

0001130144false00011301442023-10-232023-10-23 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) October 23, 2023

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On October 23, 2023, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and nine-month periods ended September 30, 2023.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated October 23, 2023

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: October 23, 2023

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

0001130144false00011301442023-07-242023-07-24 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) July 24, 2023

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices)             (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On July 24, 2023, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and six-month periods ended June 30, 2023.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

19

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated July 24, 2023

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: July 24, 2023

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​

0001130144false00011301442023-04-242023-04-24 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) April 24, 2023

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On April 24, 2023, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three-month period ended March 31, 2023.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

19

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated April 24, 2023

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: April 24, 2023

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​

0001130144false00011301442023-01-302023-01-30 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) January 30, 2023

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On January 30, 2023, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the quarter and year ended December 31, 2022. A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated January 30, 2023

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: January 30, 2023

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

0001130144false00011301442022-10-242022-10-24 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) October 24, 2022

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On October 24, 2022, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and nine-month periods ended September 30, 2022.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated October 24, 2022

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: October 24, 2022

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

0001130144false00011301442022-07-252022-07-25 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) July 25, 2022

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices)             (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On July 25, 2022, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and six-month periods ended June 30, 2022.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

19

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated July 25, 2022

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: July 25, 2022

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​

0001130144false00011301442022-04-252022-04-25 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) April 25, 2022

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On April 25, 2022, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three-month period ended March 31, 2022.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

19

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated April 25, 2022

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: April 25, 2022

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​

0001130144false00011301442022-01-242022-01-24 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) January 24, 2022

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On January 24, 2022, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the quarter and year ended December 31, 2021.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated January 24, 2022

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: January 24, 2022

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​

0001130144false00011301442021-10-252021-10-25 ​ ​

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549 Form 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported) October 25, 2021

SIERRA BANCORP

(Exact name of registrant as specified in its charter)

​ ​

​

​

California 000-33063 33-0937517

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

86 North Main Street, Porterville, CA 93257

(Address of principal executive offices) (Zip code)

​ (559) 782-4900 (Registrant’s telephone number including area code) Not applicable (Former name or former address, if changed since last report) Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below): ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act:

​

​

Title of each class ​ Trading Symbol(s) ​ Name of each exchange on which registered

Common Stock, no par value ​

BSRR

​ NASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ ​

ITEM 2.02RESULTS OF OPERATIONS AND FINANCIAL CONDITION

On October 25, 2021, Sierra Bancorp issued a press release announcing its unaudited consolidated financial results for the three- and nine-month periods ended September 30, 2021.  A copy of the press release is attached as Exhibit 99.1 to this Current Report. The information in this report (including Exhibit 99.1) is being furnished pursuant to Item 2.02 and shall not be deemed to be “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be deemed to be incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act.

ITEM 9.01FINANCIAL STATEMENTS AND EXHIBITS

(d)Exhibits. The information required to be furnished pursuant to this item is set forth in the Exhibit Index which appears below, immediately before the signatures.

EXHIBIT INDEX

Exhibit No.

Description

​ ​ ​

99.1 ​ Press release issued by Sierra Bancorp dated October 25, 2021

104 ​ Cover Page Interactive Data File (formatted in Inline XBRL and contained in Exhibit 101)

​ ​

SIGNATURES

Pursuant to the requirements of the Securities and Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. ​ ​ ​ ​ ​

​ Executive Vice President & Chief Financial Officer

​ ​ ​ ​ Dated: October 25, 2021

SIERRA BANCORP

By: /s/ Christopher G. Treece​ ​ Christopher G. Treece Executive Vice President & Chief Financial Officer

​ ​ ​