<SEC-DOCUMENT>0000950170-24-040134-index.html : 20240402
<SEC-HEADER>0000950170-24-040134.hdr.sgml : 20240402
<ACCEPTANCE-DATETIME>20240402160510
ACCESSION NUMBER:		0000950170-24-040134
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20240327
FILED AS OF DATE:		20240402
DATE AS OF CHANGE:		20240402

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BYERS SANDRA L
		CENTRAL INDEX KEY:			0002017961
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26481
		FILM NUMBER:		24814131

	MAIL ADDRESS:	
		STREET 1:		220 LIBERTY STREET
		CITY:			WARSAW
		STATE:			NY
		ZIP:			14569

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			FINANCIAL INSTITUTIONS INC
		CENTRAL INDEX KEY:			0000862831
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		ORGANIZATION NAME:           	02 Finance
		IRS NUMBER:				160816610
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		220 LIBERTY STREET
		CITY:			WARSAW
		STATE:			NY
		ZIP:			14569
		BUSINESS PHONE:		5857861100

	MAIL ADDRESS:	
		STREET 1:		220 LIBERTY STREET
		CITY:			WARSAW
		STATE:			NY
		ZIP:			14569
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>ownership.xml
<DESCRIPTION>3
<TEXT>
Document 1 - file: ownership.html

Document 1 - RAW XML: ownership.xml

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24.1
<SEQUENCE>2
<FILENAME>fisi-ex24_1.htm
<DESCRIPTION>EX-24.1
<TEXT>
Document 2 - file: fisi-ex24_1.htm

</DOCUMENT>
</SEC-DOCUMENT>