<SEC-DOCUMENT>0001193125-18-250266-index.html : 20180816
<SEC-HEADER>0001193125-18-250266.hdr.sgml : 20180816
<ACCEPTANCE-DATETIME>20180816090727
ACCESSION NUMBER:		0001193125-18-250266
CONFORMED SUBMISSION TYPE:	S-3
PUBLIC DOCUMENT COUNT:		8
FILED AS OF DATE:		20180816
DATE AS OF CHANGE:		20180816

FILER:

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

	FILING VALUES:
		FORM TYPE:		S-3
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-226861
		FILM NUMBER:		181022459

	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>S-3
<SEQUENCE>1
<FILENAME>d606189ds3.htm
<DESCRIPTION>S-3
<TEXT>
Document 1 - file: d606189ds3.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>2
<FILENAME>d606189dex51.htm
<DESCRIPTION>EX-5.1
<TEXT>
Document 2 - file: d606189dex51.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-12.1
<SEQUENCE>3
<FILENAME>d606189dex121.htm
<DESCRIPTION>EX-12.1
<TEXT>
Document 3 - file: d606189dex121.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>4
<FILENAME>d606189dex231.htm
<DESCRIPTION>EX-23.1
<TEXT>
Document 4 - file: d606189dex231.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-25.1
<SEQUENCE>5
<FILENAME>d606189dex251.htm
<DESCRIPTION>EX-25.1
<TEXT>
Document 5 - file: d606189dex251.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>6
<FILENAME>g606189g50u27.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 6 - file: g606189g50u27.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>7
<FILENAME>g606189page38.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 7 - file: g606189page38.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>8
<FILENAME>g606189page39.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 8 - file: g606189page39.jpg

</DOCUMENT>
</SEC-DOCUMENT>