<SEC-DOCUMENT>0001562180-21-004256.txt : 20210614
<SEC-HEADER>0001562180-21-004256.hdr.sgml : 20210614
<ACCEPTANCE-DATETIME>20210614174123
ACCESSION NUMBER:		0001562180-21-004256
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210610
FILED AS OF DATE:		20210614
DATE AS OF CHANGE:		20210614

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Valentine Keith
		CENTRAL INDEX KEY:			0001289408

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38701
		FILM NUMBER:		211015778

	MAIL ADDRESS:	
		STREET 1:		7475 LUSK BLVD.
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121

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>2021-06-10</periodOfReport>

    <notSubjectToSection16>false</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001289408</rptOwnerCik>
            <rptOwnerName>Valentine Keith</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>true</isDirector>
            <isOfficer>false</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-06-10</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3848.00</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>44019.00</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 be vesting 100% upon
the earlier of (i) the next annual general meeting of the stockholders of the Company or (ii) the date one year from the Vesting Commencement Date, subject to the Reporting Person's continuous service as a member of the Company's Board of Directors until such
date.</footnote>
        <footnote id="F2">Includes 3,848 shares issuable on 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 Keith C. Valentine</signatureName>
        <signatureDate>2021-06-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
