<SEC-DOCUMENT>0001562180-21-000253.txt : 20210107
<SEC-HEADER>0001562180-21-000253.hdr.sgml : 20210107
<ACCEPTANCE-DATETIME>20210107173537
ACCESSION NUMBER:		0001562180-21-000253
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210105
FILED AS OF DATE:		20210107
DATE AS OF CHANGE:		20210107

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			FRANCIS LAURA
		CENTRAL INDEX KEY:			0001218802

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38701
		FILM NUMBER:		21515001

	MAIL ADDRESS:	
		STREET 1:		C/O SI-BONE, INC.
		STREET 2:		471 EL CAMINO REAL, SUITE 101
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95050

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SI-BONE, Inc.
		CENTRAL INDEX KEY:			0001459839
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				262216351
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		471 EL CAMINO REAL, SUITE 101
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95050
		BUSINESS PHONE:		4082070700

	MAIL ADDRESS:	
		STREET 1:		471 EL CAMINO REAL, SUITE 101
		CITY:			SANTA CLARA
		STATE:			CA
		ZIP:			95050

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SI-Bone Inc.
		DATE OF NAME CHANGE:	20090326
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primarydocument.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-01-05</periodOfReport>

    <notSubjectToSection16>false</notSubjectToSection16>

    <issuer>
        <issuerCik>0001459839</issuerCik>
        <issuerName>SI-BONE, Inc.</issuerName>
        <issuerTradingSymbol>SIBN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001218802</rptOwnerCik>
            <rptOwnerName>FRANCIS LAURA</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SI-BONE, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>471 EL CAMINO REAL, SUITE 101</rptOwnerStreet2>
            <rptOwnerCity>SANTA CLARA</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95050</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>Chief Financial Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-01-05</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>49280.00</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>180616.00</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Reflects shares issuable on the settlement of restricted stock units granted to the Reporting Person. Each restricted stock unit represents a
contingent right to receive one share of the Issuer's common stock. The shares subject to the restricted stock unit will vest over four
years beginning on January 1, 2021 and will be released in quarterly installments commencing on May 15, 2021, subject to the Reporting
Person's continued service through each relevant vesting date.</footnote>
        <footnote id="F2">Includes 121,456 shares issuable on the settlement of restricted stock units granted to the Reporting Person. Each restricted stock unit represents a contingent right to receive one share of the Issuer's common stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Michael A. Pisetsky, Attorney-in-Fact for Laura A. Francis</signatureName>
        <signatureDate>2021-01-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
