UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER
PURSUANT TO RULE 13a-16 OR 15d-16 UNDER
THE SECURITIES EXCHANGE ACT OF 1934

For the month of May 2026

Commission File Number: 001-38049

Azul S.A.
(Name of Registrant)

Edifício Jatobá, 8th Floor, Condomínio Castelo Branco Office Park
Avenida Marcos Penteado de Ulhôa Rodrigues, No. 939
Tamboré, Barueri, SP, 06460-040, Brazil
+55 (11) 4831 2880
(Address of Principal Executive Office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):

Unaudited Interim Financial Statements for the First Quarter of 2026

Attached hereto as Exhibit 99.1 are the unaudited interim consolidated financial statements of Azul S.A. as of and for the three-month period ended March 31, 2026.

EXHIBIT INDEX

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, thereunto duly authorized.

Date: May 19, 2026

Azul S.A.

By: /s/ Antonio Carlos Garcia
Name: Antonio Carlos Garcia
Title: Chief Financial Officer