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sui-20260224false000091259300009125932026-02-242026-02-24

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: February 24, 2026 (Date of earliest event reported)

SUN COMMUNITIES, INC

(Exact name of registrant as specified in its charter)

Maryland1-1261638-2730780 (State or other jurisdiction of incorporation)Commission File Number(IRS Employer Identification No.)

27777 Franklin Rd.Suite 300,Southfield,Michigan 48034 (Address of Principal Executive Offices) (Zip Code)

(248) 208-2500 (Registrant’s telephone number, including area code)

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:

☐ 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, $0.01 par value SUI 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 24, 2026, Sun Communities, Inc. (the "Company") issued a press release, furnished as Exhibit 99.1 and incorporated herein by reference, announcing its financial results for the period ended December 31, 2025, and certain other information.

The Company will hold an investor conference call and webcast at 11:00 a.m. ET on February 25, 2026 to discuss the financial results for the period ended December 31, 2025.

The information contained in this Item 2.02, including Exhibit 99.1, is being furnished and shall not be deemed to be "filed" for purposes of the Securities Exchange Act of 1934, as amended (the "Exchange Act").

Item 9.01 Financial Statements and Exhibits

(d)        Exhibits.

Exhibit No. Description

99.1Press release dated February 24, 2026

104Cover Page Interactive Data File (embedded within the 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.

SUN COMMUNITIES, INC.

Dated: February 24, 2026By: /s/ Fernando Castro-Caratini Fernando Castro-Caratini, Executive Vice President, Chief Financial Officer, Secretary and Treasurer

sui-20251029false000091259300009125932025-10-292025-10-29

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: October 29, 2025 (Date of earliest event reported)

SUN COMMUNITIES, INC

(Exact name of registrant as specified in its charter)

Maryland1-1261638-2730780 (State or other jurisdiction of incorporation)Commission File Number(IRS Employer Identification No.)

27777 Franklin Rd.Suite 300,Southfield,Michigan 48034 (Address of Principal Executive Offices) (Zip Code)

(248) 208-2500 (Registrant’s telephone number, including area code)

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:

☐ 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, $0.01 par value SUI 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 October 29, 2025, Sun Communities, Inc. (the "Company") issued a press release, furnished as Exhibit 99.1 and incorporated herein by reference, announcing its financial results for the period ended September 30, 2025, and certain other information.

The Company will hold an investor conference call and webcast at 2:00 p.m. ET on October 30, 2025 to discuss the financial results for the period ended September 30, 2025.

The information contained in this Item 2.02, including Exhibit 99.1, is being furnished and shall not be deemed to be "filed" for purposes of the Securities Exchange Act of 1934, as amended (the "Exchange Act").

Item 9.01 Financial Statements and Exhibits

(d)        Exhibits.

Exhibit No. Description

99.1Press release dated October 29, 2025

104Cover Page Interactive Data File (embedded within the 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.

SUN COMMUNITIES, INC.

Dated: October 29, 2025By: /s/ Fernando Castro-Caratini Fernando Castro-Caratini, Executive Vice President, Chief Financial Officer, Secretary and Treasurer