    <SEC-DOCUMENT>0001564590-20-020334-index.html : 20200501
    <SEC-HEADER>0001564590-20-020334.hdr.sgml : 20200501
    <ACCEPTANCE-DATETIME>20200430211535
    ACCESSION NUMBER:		0001564590-20-020334
    CONFORMED SUBMISSION TYPE:	8-K
    PUBLIC DOCUMENT COUNT:		31
    CONFORMED PERIOD OF REPORT:	20200501
    ITEM INFORMATION:		Regulation FD Disclosure
    ITEM INFORMATION:		Financial Statements and Exhibits
    FILED AS OF DATE:		20200501
    DATE AS OF CHANGE:		20200430

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			BYLINE BANCORP, INC.
    		CENTRAL INDEX KEY:			0001702750
    		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
    		IRS NUMBER:				363012593

    	FILING VALUES:
    		FORM TYPE:		8-K
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-38139
    		FILM NUMBER:		20838059

    	BUSINESS ADDRESS:
    		BUSINESS PHONE:		773-244-7000

    	MAIL ADDRESS:
    		STREET 1:		180 NORTH LASALLE STREET, SUITE 300
    		CITY:			CHICAGO
    		STATE:			IL
    		ZIP:			60601
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>8-K
    <SEQUENCE>1
    <FILENAME>by-8k_20200430.htm
    <DESCRIPTION>8-K
    <TEXT>
    Document 1 - file: by-8k_20200430.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>EX-99.1
    <SEQUENCE>2
    <FILENAME>by-ex991_6.htm
    <DESCRIPTION>EX-99.1
    <TEXT>
    Document 2 - file: by-ex991_6.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
    <FILENAME>grpmqxivlkmv000006.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: grpmqxivlkmv000006.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>4
    <FILENAME>grpmqxivlkmv000014.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 4 - file: grpmqxivlkmv000014.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>5
    <FILENAME>grpmqxivlkmv000027.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 5 - file: grpmqxivlkmv000027.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>6
    <FILENAME>grpmqxivlkmv000016.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 6 - file: grpmqxivlkmv000016.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>7
    <FILENAME>grpmqxivlkmv000026.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 7 - file: grpmqxivlkmv000026.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>8
    <FILENAME>grpmqxivlkmv000011.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 8 - file: grpmqxivlkmv000011.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>9
    <FILENAME>grpmqxivlkmv000018.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 9 - file: grpmqxivlkmv000018.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>10
    <FILENAME>grpmqxivlkmv000021.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 10 - file: grpmqxivlkmv000021.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>11
    <FILENAME>grpmqxivlkmv000005.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 11 - file: grpmqxivlkmv000005.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>12
    <FILENAME>grpmqxivlkmv000025.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 12 - file: grpmqxivlkmv000025.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>13
    <FILENAME>grpmqxivlkmv000001.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 13 - file: grpmqxivlkmv000001.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>14
    <FILENAME>grpmqxivlkmv000004.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 14 - file: grpmqxivlkmv000004.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>15
    <FILENAME>grpmqxivlkmv000010.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 15 - file: grpmqxivlkmv000010.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>16
    <FILENAME>grpmqxivlkmv000029.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 16 - file: grpmqxivlkmv000029.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>17
    <FILENAME>grpmqxivlkmv000019.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 17 - file: grpmqxivlkmv000019.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>18
    <FILENAME>grpmqxivlkmv000008.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 18 - file: grpmqxivlkmv000008.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>19
    <FILENAME>grpmqxivlkmv000013.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 19 - file: grpmqxivlkmv000013.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>20
    <FILENAME>grpmqxivlkmv000002.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 20 - file: grpmqxivlkmv000002.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>21
    <FILENAME>grpmqxivlkmv000017.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 21 - file: grpmqxivlkmv000017.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>22
    <FILENAME>grpmqxivlkmv000012.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 22 - file: grpmqxivlkmv000012.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>23
    <FILENAME>grpmqxivlkmv000003.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 23 - file: grpmqxivlkmv000003.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>24
    <FILENAME>grpmqxivlkmv000015.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 24 - file: grpmqxivlkmv000015.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>25
    <FILENAME>grpmqxivlkmv000022.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 25 - file: grpmqxivlkmv000022.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>26
    <FILENAME>grpmqxivlkmv000023.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 26 - file: grpmqxivlkmv000023.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>27
    <FILENAME>grpmqxivlkmv000028.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 27 - file: grpmqxivlkmv000028.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>28
    <FILENAME>grpmqxivlkmv000007.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 28 - file: grpmqxivlkmv000007.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>29
    <FILENAME>grpmqxivlkmv000024.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 29 - file: grpmqxivlkmv000024.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>30
    <FILENAME>grpmqxivlkmv000009.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 30 - file: grpmqxivlkmv000009.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>31
    <FILENAME>grpmqxivlkmv000020.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 31 - file: grpmqxivlkmv000020.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>