Byline Bancorp (BY) 10-Q 2023 Q3 Quarterly report

EXHIBIT 32.1

CERTIFICATIONS PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report of Byline Bancorp, Inc. (the “Company”) on Form 10-Q for the period ended September 30, 2023 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), the undersigned, the Chief Executive Officer and Chief Financial Officer of the Company, each hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to his or her knowledge:

1. The Report fully complies with the requirements of Sections 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/	Roberto R. Herencia
	Roberto R. Herencia
	Chief Executive Officer
	(Principal Executive Officer)
	November 3, 2023
/s/	Thomas J. Bell
	Thomas J. Bell
	Executive Vice President, Chief Financial Officer and Treasurer
	(Principal Financial Officer)
	November 3, 2023