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        <pctVal>2.010016289123</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Calvert Small Cap Fund</name>
        <lei>549300MIJR64EECJ6M85</lei>
        <title>Calvert Small Cap Fund</title>
        <cusip>13161P672</cusip>
        <identifiers>
          <isin value="US13161P6723"/>
        </identifiers>
        <balance>277256.76900000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>10142052.61000000</valUSD>
        <pctVal>3.504280215234</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Calvert Equity Fund</name>
        <lei>5493008KHIQHXPKPLB89</lei>
        <title>Calvert Equity Fund</title>
        <cusip>131582280</cusip>
        <identifiers>
          <isin value="US1315822809"/>
        </identifiers>
        <balance>148679.42200000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>13062974.02000000</valUSD>
        <pctVal>4.513516461674</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Chicago Board of Trade</name>
        <lei>549300EX04Q2QBFQTQ27</lei>
        <title>US 5YR NOTE (CBT) SEP21 XCBT 20210930</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Bloomberg Identifier" value="BBG00YN8BCD9"/>
        </identifiers>
        <balance>-55.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>20560.60000000</valUSD>
        <pctVal>0.007104094857</pctVal>
        <payoffProfile>N/A</payoffProfile>
        <assetCat>DIR</assetCat>
        <issuerConditional desc="derivative" issuerCat="OTHER"/>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <derivativeInfo>
          <futrDeriv derivCat="FUT">
            <counterparties>
              <counterpartyName>Chicago Board of Trade</counterpartyName>
              <counterpartyLei>549300EX04Q2QBFQTQ27</counterpartyLei>
            </counterparties>
            <payOffProf>Short</payOffProf>
            <descRefInstrmnt>
              <indexBasketInfo>
                <indexName>5 Year US Treasury Note</indexName>
                <indexIdentifier>FVU1 Comdty</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <expDate>2021-09-30</expDate>
            <notionalAmt>-6809193.44000000</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>20560.60000000</unrealizedAppr>
          </futrDeriv>
        </derivativeInfo>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Calvert International Responsible Index Fund</name>
        <lei>5493002R7L7YSTUULM88</lei>
        <title>Calvert International Responsible Index Fund</title>
        <cusip>13161Y848</cusip>
        <identifiers>
          <isin value="US13161Y8488"/>
        </identifiers>
        <balance>671438.71200000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>20559453.36000000</valUSD>
        <pctVal>7.103698670862</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Calvert US Mid Cap Core Responsible Index Fund</name>
        <lei>549300I74Z158YTBPO44</lei>
        <title>Calvert US Mid Cap Core Responsible Index Fund</title>
        <cusip>13161Y301</cusip>
        <identifiers>
          <isin value="US13161Y3018"/>
        </identifiers>
        <balance>367314.90400000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>14549343.35000000</valUSD>
        <pctVal>5.027086528399</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Calvert International Equity Fund</name>
        <lei>549300DYXGATLWKZ1990</lei>
        <title>Calvert International Equity Fund</title>
        <cusip>131649741</cusip>
        <identifiers>
          <isin value="US1316497411"/>
        </identifiers>
        <balance>1103704.04400000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>29711712.86000000</valUSD>
        <pctVal>10.26598574664</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
    </invstOrSecs>
    <explntrNotes>
      <explntrNote note="Monthly returns presented in Item B.5(a) have been calculated without deducting any applicable sales loads or redemption fees." noteItem="B.5.a"/>
    </explntrNotes>
    <signature>
      <ncom:dateSigned>2021-07-26</ncom:dateSigned>
      <ncom:nameOfApplicant>CALVERT SOCIAL INVESTMENT FUND</ncom:nameOfApplicant>
      <ncom:signature>James Kirchner</ncom:signature>
      <ncom:signerName>James Kirchner</ncom:signerName>
      <ncom:title>Treasurer</ncom:title>
    </signature>
  </formData>
  <documents>XXXX</documents>
</edgarSubmission>
