ONTF

ontf-202602250001110611FALSE00011106112026-02-252026-02-25

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): February 25, 2026

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

301 Howard Street,Suite 1100 San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On February 25, 2026, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the fourth quarter and full year ended December 31, 2025. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01    Exhibits. (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated February 25, 2026

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: February 25, 2026 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-202511100001110611FALSE00011106112025-11-102025-11-10

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): November 10, 2025

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

301 Howard Street,Suite 1100 San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On November 10, 2025, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the third quarter ended September 30, 2025. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 7.01     Regulation FD Disclosure. The Company has received indications of interest for a potential acquisition of the Company. The Board is evaluating the indications of interest with Goldman Sachs, its financial advisor. There can be no assurances as to the outcome of this process.

This document contains “forward-looking statements” under applicable securities laws, including express or implied statements about the outcome of our process to evaluate indications of interest, which are subject to inherent risks and uncertainties, including our ability to attract new customers and expand sales to existing customers; declines in our growth rate; fluctuation in our performance; our history of net losses; competition; technological development in our markets; decline in demand for our solutions; our ability to expand our sales and marketing capabilities and otherwise achieve our growth; the impact of the resumption of in-person marketing activities on our customer growth rate; disruptions or other issues with our technology or third-party services; compliance with data privacy, import and export controls, customs, sanctions and other laws and regulations; intellectual property matters; and matters relating to our common stock, along with the other risks and uncertainties discussed in the filings we make from time to time with the Securities and Exchange Commission. Actual results may differ materially from those indicated in forward-looking statements, and you should not place undue reliance on them. All statements herein are based only on information currently available to us and speak only as of the date hereof. Except as required by law, we undertake no obligation to update any such statement.

Item 9.01    Exhibits. (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated November 10, 2025

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly

ontf-202508070001110611FALSE00011106112025-08-072025-08-07

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): August 7, 2025

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On August 7, 2025, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the second quarter ended June 30, 2025. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Exhibits. (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated August 7, 2025

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: August 7, 2025 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-202505070001110611FALSE00011106112025-05-072025-05-07

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): May 7, 2025

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On May 7, 2025, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the first quarter ended March 31, 2025. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 8.01 Other Events.

Repurchase Program On May 7, 2025, the Company announced that its Board of Directors unanimously approved a share repurchase program pursuant to which the Company may purchase up to $50 million of its common stock.

Under the repurchase program, the Company may purchase shares of common stock on a discretionary basis from time to time through open market repurchases, privately negotiated transactions, or other means, including through Rule 10b5-1 trading plans. The Company expects repurchases under the program to extend over multiple quarters.

The timing and number of shares repurchased under the program will depend on a variety of factors, including stock price, trading volume, and general business and market conditions. The repurchase program does not obligate the Company to acquire any particular amount of common stock and may be modified, suspended, or discontinued at any time at the Company’s discretion. Repurchases under this program will be funded from the company’s existing cash and cash equivalents or future cash flow.

As of March 31, 2025, the Company had $181.0 million in cash, cash equivalents and marketable securities.

Forward-Looking Statements

This report contains “forward-looking statements” under applicable securities laws. Such statements can be identified by words such as: “outlook,” “expect,” “target,” “believe,” “plan,” “future,” “may,” “should,” “will,” and similar references to future periods. Forward-looking statements include express or implied statements regarding the timing, price and amount of potential repurchases of common stock, our expected financial and operating results, the execution of our capital return program, the size of our market opportunity, the success of our new products and capabilities, including our new AI-powered Analytics and Content Engine, and other statements regarding our ability to achieve our business strategies, growth, or other future events or conditions. Such statements are based on our current beliefs, expectations, and assumptions about future events or conditions, which are subjec

ontf-202502250001110611FALSE00011106112025-02-252025-02-25

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): February 25, 2025

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On February 25, 2025, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the fourth quarter and full year ended December 31, 2024. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Exhibits (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated February 25, 2025

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: February 25, 2025 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-202411070001110611FALSE00011106112024-11-072024-11-07

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): November 7, 2024

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On November 7, 2024, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the third quarter ended September 30, 2024. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Exhibits (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated November 7, 2024

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: November 7, 2024 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-202408060001110611FALSE00011106112024-08-062024-08-06

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): August 6, 2024

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On August 6, 2024, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the second quarter ended June 30, 2024. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Exhibits (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated August 6, 2024

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: August 6, 2024 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-202405070001110611FALSE00011106112024-05-072024-05-07

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): May 7, 2024

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On May 7, 2024, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the first quarter ended March 31, 2024. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Exhibits (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated May 7, 2024

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: May 7, 2024 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-20240222February 22, 20240001110611FALSE00011106112024-02-222024-02-22

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): February 22, 2024

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On February 22, 2024, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the fourth quarter and full year ended December 31, 2023. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Exhibits (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated February 22, 2024

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: February 22, 2024 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-202311070001110611FALSE00011106112023-11-072023-11-07

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): November 7, 2023

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On November 7, 2023, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the third quarter ended September 30, 2023. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Exhibits (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated November 7, 2023

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: November 7, 2023 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-202308080001110611FALSE00011106112023-08-082023-08-08

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): August 8, 2023

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFThe New York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On August 8, 2023, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the second quarter ended June 30, 2023. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Exhibits (d) Exhibits.

Exhibit No.Description

99.1 Press Release dated August 8, 2023

104Cover Page Interactive Data File (formatted as Inline XBRL document)

SIGNATURES

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

Date: August 8, 2023ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

ontf-202305090001110611FALSE00011106112023-05-092023-05-09

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): May 9, 2023

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFNew York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On May 9, 2023, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the first quarter ended March 31, 2023. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01     Financial Statements and Exhibits. (d) Exhibits.

Exhibit No.Description of Exhibits

99.1 Press Release dated May 9, 2023

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

2

SIGNATURES

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

Date: May 9, 2023 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

3

ontf-202302280001110611FALSE00011106112023-02-282023-02-28

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): February 28, 2023

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFNew York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On February 28, 2023, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the fourth quarter and full year ended December 31, 2022. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference. Except as otherwise provided in Item 8.01, the information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 2.05     Costs Associated with Exit or Disposal Activities. On February 28, 2022, in an effort to streamline its organization, the Company committed to a restructuring plan to reduce expenses (the “Plan”). In connection with the Plan, the Company currently estimates it will incur a charge of between approximately $2.8 million to $3.3 million by the end of the first quarter of 2023, which consists of $1.5 million to $1.8 million for the reduction in force in cash severance costs and a $1.3 million to $1.5 million impairment charge for underutilized real estate. This is in addition to the $1.0 million charge incurred in January 2023 pursuant to a separate expense reduction plan. The Company expects the Plan to be substantially complete by the end of the first quarter of 2023 but may incur additional charges in the following quarter. The estimates of expenses that the Company expects to incur in connection with the Plan are subject to a number of assumptions and actual results may differ materially. The Company may also incur additional expenses not currently contemplated due to events that may occur as a result of, or that are associated with, the Plan.

Item 8.01     Other Events. The three paragraphs under the heading “$100 Million Capital Return Program” in the press release attached hereto as Exhibit 99.1 are incorporated by reference herein.

Item 9.01     Financial Statements and Exhibits. (d) Exhibits.

Exhibit No.Description of Exhibits

99.1 Press Release dated February 28, 2023

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

2

SIGNATURES

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

Date: February 28, 2023 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

3

ontf-202211090001110611FALSE00011106112022-11-092022-11-09

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): November 9, 2022

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFNew York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On November 9, 2022, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the third quarter ended September 30, 2022. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference. The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01     Financial Statements and Exhibits. (d) Exhibits.

Exhibit No.Description of Exhibits

99.1 Press Release dated November 9, 2022

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

2

SIGNATURES

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

Date: November 9, 2022 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

3

ontf-202208090001110611FALSE00011106112022-08-092022-08-09

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): August 9, 2022

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFNew York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On August 9, 2022, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the second quarter ended June 30, 2022. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference. The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01     Financial Statements and Exhibits. (d) Exhibits.

Exhibit No.Description of Exhibits

99.1 Press Release dated August 9, 2022

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

2

SIGNATURES

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

Date: August 9, 2022 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

3

ontf-202205100001110611FALSE00011106112022-05-102022-05-10

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): May 10, 2022

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFNew York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On May 10, 2022, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the first quarter ended March 31, 2022. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference. The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01     Financial Statements and Exhibits. (d) Exhibits.

Exhibit No.Description of Exhibits

99.1 Press Release dated May 10, 2022

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

2

SIGNATURES

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

Date: May 10, 2022 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

3

ontf-202202280001110611FALSE00011106112022-02-282022-02-28

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): February 28, 2022

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFNew York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On February 28, 2022, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the fourth quarter and full year ended December 31, 2021. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference. The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01     Financial Statements and Exhibits. (d) Exhibits.

Exhibit No.Description of Exhibits

99.1 Press Release dated February 28, 2022

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

2

SIGNATURES

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

Date: February 28, 2022 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

3

ontf-202111090001110611FALSE00011106112021-11-092021-11-09

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): November 9, 2021

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3996594-3292599 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

50 Beale Street, 8th Floor San Francisco,

CA94105

(Address of principal executive offices)(Zip Code)

(415) 369-8000 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐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 classTrading SymbolName of each exchange on which registered Common stock, par value $0.0001 per shareONTFNew York Stock Exchange

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 2.02     Results of Operations and Financial Condition. On November 9, 2021, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the third quarter ended September 30, 2021. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference. The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01     Financial Statements and Exhibits. (d) Exhibits.

Exhibit No.Description of Exhibits

99.1 Press Release dated November 9, 2021.

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

2

SIGNATURES

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

Date: November 9, 2021 ON24, Inc.

By:/s/ Steven Vattuone Steven Vattuone Chief Financial Officer

3

8-K 1 d153590d8k.htm 8-K

8-K

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): August 10, 2021

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware

001-39965

94-3292599

(State or other jurisdictionof incorporation)

(CommissionFile Number)

(IRS EmployerIdentification No.)

50 Beale Street, 8th Floor

San Francisco, CA 94105

94105

(Address of principal executive offices)

(Zip Code)

(415) 369-8000

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ 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

TradingSymbol

Name of each exchangeon which registered

Common stock, par value $0.0001 per share

ONTF

The New York Stock Exchange

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 2.02 Results of Operations and Financial Condition.

On August 10, 2021, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the second quarter ended June 30, 2021. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference. The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.

Description of Exhibits

99.1

Press Release dated August 10, 2021.

2

SIGNATURES

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

Date: August 10, 2021

ON24, Inc.

By:

/s/ Steven Vattuone

Steven Vattuone

Chief Financial Officer

3

8-K 1 d924168d8k.htm 8-K

8-K

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): May 12, 2021

ON24, INC.

(Exact name of registrant as specified in its charter)

Delaware

001-39965

94-3292599

(State or other jurisdictionof incorporation)

(CommissionFile Number)

(IRS EmployerIdentification No.)

50 Beale Street, 8th Floor

San Francisco, CA 94105

94105

(Address of principal executive offices)

(Zip Code)

(415) 369-8000

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ 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

TradingSymbol

Name of each exchangeon which registered

Common stock, par value $0.0001 per share

ONTF

The New York Stock Exchange

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 2.02 Results of Operations and Financial Condition.

On May 12, 2021, ON24, Inc. (the “Company”), issued a press release announcing its financial results for the first quarter ended March 31, 2021. A copy of the press release is furnished herewith as Exhibit 99.1 and incorporated herein by reference. The information contained in this report, including Exhibit 99.1 attached hereto, is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.

Description of Exhibits

99.1

Press Release dated May 12, 2021.

2

SIGNATURES

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

Date: May 12, 2021

ON24, Inc.

By:

/s/ Steven Vattuone

Steven Vattuone

Chief Financial Officer

3