<SEC-DOCUMENT>0001558370-20-010230-index.html : 20200810
<SEC-HEADER>0001558370-20-010230.hdr.sgml : 20200810
<ACCEPTANCE-DATETIME>20200810170343
ACCESSION NUMBER:		0001558370-20-010230
CONFORMED SUBMISSION TYPE:	S-3
PUBLIC DOCUMENT COUNT:		6
FILED AS OF DATE:		20200810
DATE AS OF CHANGE:		20200810

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			OLD SECOND BANCORP INC
		CENTRAL INDEX KEY:			0000357173
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				363143493
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-3
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-243746
		FILM NUMBER:		201090190

	BUSINESS ADDRESS:	
		STREET 1:		37 S RIVER ST
		CITY:			AURORA
		STATE:			IL
		ZIP:			60507
		BUSINESS PHONE:		6308920202

	MAIL ADDRESS:	
		STREET 1:		37 SOUTH RIVER STREET
		CITY:			AURORA
		STATE:			IL
		ZIP:			60507
</SEC-HEADER>
<DOCUMENT>
<TYPE>S-3
<SEQUENCE>1
<FILENAME>tmb-20200810xs3.htm
<DESCRIPTION>S-3
<TEXT>
Document 1 - file: tmb-20200810xs3.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-4.8
<SEQUENCE>2
<FILENAME>tmb-20200810xex4d8.htm
<DESCRIPTION>EX-4.8
<TEXT>
Document 2 - file: tmb-20200810xex4d8.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>3
<FILENAME>tmb-20200810xex5d1.htm
<DESCRIPTION>EX-5.1
<TEXT>
Document 3 - file: tmb-20200810xex5d1.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>4
<FILENAME>tmb-20200810xex23d1.htm
<DESCRIPTION>EX-23.1
<TEXT>
Document 4 - file: tmb-20200810xex23d1.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>5
<FILENAME>tmb-20200810xex5d1001.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 5 - file: tmb-20200810xex5d1001.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>6
<FILENAME>tmb-20200810xs3001.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 6 - file: tmb-20200810xs3001.jpg

</DOCUMENT>
</SEC-DOCUMENT>