<SEC-DOCUMENT>0001209191-21-022349.txt : 20210322
<SEC-HEADER>0001209191-21-022349.hdr.sgml : 20210322
<ACCEPTANCE-DATETIME>20210322162213
ACCESSION NUMBER:		0001209191-21-022349
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20210319
FILED AS OF DATE:		20210322
DATE AS OF CHANGE:		20210322

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Dumbleton Sonia Marie
		CENTRAL INDEX KEY:			0001576956

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-26481
		FILM NUMBER:		21761564

	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]
		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>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-03-19</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000862831</issuerCik>
        <issuerName>FINANCIAL INSTITUTIONS INC</issuerName>
        <issuerTradingSymbol>FISI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001576956</rptOwnerCik>
            <rptOwnerName>Dumbleton Sonia Marie</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>220 LIBERTY STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WARSAW</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>14569</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6266</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Unit</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-03-19</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>582</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2024-03-19</value>
            </exerciseDate>
            <expirationDate>
                <value>2024-03-19</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>582</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>582</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each restricted stock unit represents a contingent right to receive one share of FISI common stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Sonia M. Dumbleton</signatureName>
        <signatureDate>2021-03-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24.4_974809
<SEQUENCE>2
<FILENAME>poa.txt
<DESCRIPTION>POA DOCUMENT
<TEXT>
LIMITED POWER OF ATTORNEY FOR SECTION 16 REPORTING OBLIGATIONS


     The undersigned hereby constitutes and appoints each of Michael D. Grover
and W. Jack Plants, II as the undersigned's true and lawful attorney-in-fact,
and grants each of them full power to act on behalf of the undersigned and in
the undersigned's name, place and stead, for the purpose of completing and
signing, on behalf of the undersigned, any Form 3, Form 4 or Form 5 (including
any amendments thereto) required or permitted to be filed by the undersigned
pursuant to Section 16 of the Securities Exchange Act of 1934, as amended (the
"Exchange Act"), with regard to the undersigned's holdings of or transactions in
the securities of Financial Institutions, Inc., and to file such forms (and
amendments thereto) with the Securities and Exchange Commission, and to do and
perform each and every act and thing requisite or necessary to be done in
connection with such forms (and amendments thereto,) as fully and to all intents
and purposes as the undersigned might or could do in person.

      The authority of Michael D. Grover and W. Jack Plants, II under this
Limited Power of Attorney shall continue until the undersigned is no longer
required to file forms under Section 16(a) of the Exchange Act with regard to
the undersigned's holdings of or transactions in the securities of Financial
Institutions, Inc., unless earlier revoked by the undersigned in writing.

      The undersigned acknowledges that Michael D. Grover and W. Jack Plants, II
are not assuming any of the undersigned's responsibilities to comply with
Section 16 of the Exchange Act.


/s/ Sonia M. Dumbleton
Signature
Name:  Sonia M. Dumbleton
Date:  March 18, 2021
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
