<SEC-DOCUMENT>0001123292-16-002248.txt : 20160510
<SEC-HEADER>0001123292-16-002248.hdr.sgml : 20160510
<ACCEPTANCE-DATETIME>20160510161411
ACCESSION NUMBER:		0001123292-16-002248
CONFORMED SUBMISSION TYPE:	3/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20160503
FILED AS OF DATE:		20160510
DATE AS OF CHANGE:		20160510

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NBT BANCORP INC
		CENTRAL INDEX KEY:			0000790359
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		IRS NUMBER:				161268674
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		52 S BROAD ST
		CITY:			NORWICH
		STATE:			NY
		ZIP:			13815
		BUSINESS PHONE:		6073372265

	MAIL ADDRESS:	
		STREET 1:		52 S. BROAD STREET
		CITY:			NORWICH
		STATE:			NY
		ZIP:			13815

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			WATT JOHN H JR
		CENTRAL INDEX KEY:			0001265126

	FILING VALUES:
		FORM TYPE:		3/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14703
		FILM NUMBER:		161635948

	MAIL ADDRESS:	
		STREET 1:		52 SOUTH BROAD STREET
		CITY:			NORWICH
		STATE:			NY
		ZIP:			13815
</SEC-HEADER>
<DOCUMENT>
<TYPE>3/A
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0206</schemaVersion>

    <documentType>3/A</documentType>

    <periodOfReport>2016-05-03</periodOfReport>

    <dateOfOriginalSubmission>2016-05-10</dateOfOriginalSubmission>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000790359</issuerCik>
        <issuerName>NBT BANCORP INC</issuerName>
        <issuerTradingSymbol>NBTB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001265126</rptOwnerCik>
            <rptOwnerName>WATT JOHN H JR</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>52 SOUTH BROAD STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>NORWICH</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>13815</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, Pres of NBT Bank, N.A.</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>NBT Bancorp Inc. Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40934</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">This amendment is being filed solely to correct a typographical error in the address of the reporting person.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ F. Sheldon Prentice, Power of Attorney</signatureName>
        <signatureDate>2016-05-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
