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              <indexBasketInfo>
                <indexName>2 Year US Treasury Note</indexName>
                <indexIdentifier>TUH0 Comdty</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <expDate>2020-03-31</expDate>
            <notionalAmt>22647411.15</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>-19911.15</unrealizedAppr>
          </futrDeriv>
        </derivativeInfo>
        <securityLending>
          <isCashCollateral>N</isCashCollateral>
          <isNonCashCollateral>N</isNonCashCollateral>
          <isLoanByFund>N</isLoanByFund>
        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Calvert International Opportunities Fund</name>
        <lei>549300125QOYCBC7IB51</lei>
        <title>Calvert International Opportunities Fund</title>
        <cusip>131649758</cusip>
        <identifiers>
          <isin value="US1316497585"/>
        </identifiers>
        <balance>981737.90900000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>17327674.09000000</valUSD>
        <pctVal>9.692717723295</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 Emerging Markets Advancement Fund</name>
        <lei>549300OOWWGW13TF0P06</lei>
        <title>Calvert Emerging Markets Advancement Fund</title>
        <cusip>131649717</cusip>
        <identifiers>
          <isin value="US1316497171"/>
        </identifiers>
        <balance>564589.18700000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>6204835.17000000</valUSD>
        <pctVal>3.470847588084</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 Mercantile Exchange</name>
        <lei>SNZ2OJLFK8MNNCLQOF39</lei>
        <title>S+P500 EMINI FUT  MAR20 XCME 20200320</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="ADI1742S2"/>
        </identifiers>
        <balance>33.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>52133.40000000</valUSD>
        <pctVal>0.029162271146</pctVal>
        <payoffProfile>N/A</payoffProfile>
        <assetCat>DE</assetCat>
        <issuerConditional desc="derivative" issuerCat="OTHER"/>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <derivativeInfo>
          <futrDeriv derivCat="FUT">
            <counterparties>
              <counterpartyName>Chicago Mercantile Exchange</counterpartyName>
              <counterpartyLei>SNZ2OJLFK8MNNCLQOF39</counterpartyLei>
            </counterparties>
            <payOffProf>Long</payOffProf>
            <descRefInstrmnt>
              <indexBasketInfo>
                <indexName>E-mini S&amp;P 500 Index</indexName>
                <indexIdentifier>ESH0 Index</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <expDate>2020-03-20</expDate>
            <notionalAmt>5279181.6</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>52133.4</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>253089.28800000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>6223465.59000000</valUSD>
        <pctVal>3.481269033062</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 Large Cap Core Responsible Index Fund</name>
        <lei>549300PO0F0AV64IR605</lei>
        <title>Calvert US Large Cap Core Responsible Index Fund</title>
        <cusip>131582298</cusip>
        <identifiers>
          <isin value="US1315822981"/>
        </identifiers>
        <balance>1730774.43000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>47613604.57000000</valUSD>
        <pctVal>26.63399752837</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>795351.43800000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>16909171.57000000</valUSD>
        <pctVal>9.458616667852</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) MAR20 XCBT 20200331</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="ADI1CW4N3"/>
        </identifiers>
        <balance>-47.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>24967.81000000</valUSD>
        <pctVal>0.013966440806</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>FVH0 Comdty</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <expDate>2020-03-31</expDate>
            <notionalAmt>-5599608.44</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>24967.81</unrealizedAppr>
          </futrDeriv>
        </derivativeInfo>
        <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>2020-01-24</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>
