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        </securityLending>
      </invstOrSec>
      <invstOrSec>
        <name>Options Clearing Corp.</name>
        <lei>549300CII6SLYGKNHA04</lei>
        <title>S+P 500 INDEX SEP21 3850 PUT</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Bloomberg Identifier" value="BBG00WMZ1RZ8"/>
        </identifiers>
        <balance>-11.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>-35750.00000000</valUSD>
        <pctVal>-0.01215399397</pctVal>
        <payoffProfile>N/A</payoffProfile>
        <assetCat>DE</assetCat>
        <issuerConditional desc="derivative" issuerCat="OTHER"/>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>1</fairValLevel>
        <derivativeInfo>
          <optionSwaptionWarrantDeriv derivCat="OPT">
            <counterparties>
              <counterpartyName>Options Clearing Corp.</counterpartyName>
              <counterpartyLei>549300CII6SLYGKNHA04</counterpartyLei>
            </counterparties>
            <putOrCall>Put</putOrCall>
            <writtenOrPur>Written</writtenOrPur>
            <descRefInstrmnt>
              <indexBasketInfo>
                <indexName>S&amp;P 500 Index</indexName>
                <indexIdentifier>SPX Index</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <shareNo>100.00000000</shareNo>
            <exercisePrice>3850.00000000</exercisePrice>
            <exercisePriceCurCd>USD</exercisePriceCurCd>
            <expDt>2021-09-17</expDt>
            <delta>XXXX</delta>
            <unrealizedAppr>2767.44000000</unrealizedAppr>
          </optionSwaptionWarrantDeriv>
        </derivativeInfo>
        <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>73.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>-27429.10000000</valUSD>
        <pctVal>-0.00932512212</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>Long</payOffProf>
            <descRefInstrmnt>
              <indexBasketInfo>
                <indexName>5 Year US Treasury Note</indexName>
                <indexIdentifier>FVU1 Comdty</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <expDate>2021-09-30</expDate>
            <notionalAmt>9037796.32000000</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>-27429.10000000</unrealizedAppr>
          </futrDeriv>
        </derivativeInfo>
        <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>385469.08700000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5180704.53000000</valUSD>
        <pctVal>1.761293751966</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 Equity Fund</name>
        <lei>549300L4S5NY62FOKA38</lei>
        <title>Calvert Emerging Markets Equity Fund</title>
        <cusip>131649766</cusip>
        <identifiers>
          <isin value="US1316497668"/>
        </identifiers>
        <balance>224115.10700000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5172576.67000000</valUSD>
        <pctVal>1.758530508289</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 Absolute Return Bond Fund</name>
        <lei>549300HDLJYKTU171023</lei>
        <title>Calvert Absolute Return Bond Fund</title>
        <cusip>13161X840</cusip>
        <identifiers>
          <isin value="US13161X8406"/>
        </identifiers>
        <balance>1025720.61300000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>15990984.36000000</valUSD>
        <pctVal>5.436484686198</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 Floating-Rate Advantage Fund</name>
        <lei>549300GG1YFY0YH1UJ86</lei>
        <title>Calvert Floating-Rate Advantage Fund</title>
        <cusip>13161X865</cusip>
        <identifiers>
          <isin value="US13161X8653"/>
        </identifiers>
        <balance>2064520.67500000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>19612946.41000000</valUSD>
        <pctVal>6.667849858943</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 Mid-Cap Fund</name>
        <lei>549300Y1UC9HCBUDKZ85</lei>
        <title>Calvert Mid-Cap Fund</title>
        <cusip>131649709</cusip>
        <identifiers>
          <isin value="US1316497098"/>
        </identifiers>
        <balance>43952.39100000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2249043.85000000</valUSD>
        <pctVal>0.764611619513</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>102094.17200000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3734604.81000000</valUSD>
        <pctVal>1.269660541308</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>102163.23500000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>8976061.83000000</valUSD>
        <pctVal>3.051608430261</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>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>United States Treasury Inflation Indexed Bonds</title>
        <cusip>9128285W6</cusip>
        <identifiers>
          <isin value="US9128285W63"/>
        </identifiers>
        <balance>5111181.56000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>5918027.37000000</valUSD>
        <pctVal>2.011962768845</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2029-01-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>0.87500000</annualizedRt>
          <isDefault>N</isDefault>
          <areIntrstPmntsInArrs>N</areIntrstPmntsInArrs>
          <isPaidKind>N</isPaidKind>
        </debtSec>
        <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>238641.22100000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>7307194.19000000</valUSD>
        <pctVal>2.484240395630</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>113575.84600000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>4498739.26000000</valUSD>
        <pctVal>1.529444751091</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>352104.49000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>9478652.87000000</valUSD>
        <pctVal>3.222475240638</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 Ultra-Short Duration Income Fund</name>
        <lei>549300IXKXR5NQT6M528</lei>
        <title>Calvert Ultra-Short Duration Income Fund</title>
        <cusip>131582314</cusip>
        <identifiers>
          <isin value="US1315823146"/>
        </identifiers>
        <balance>1828821.35200000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>18178484.24000000</valUSD>
        <pctVal>6.180173087796</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 Short-Duration Income Fund</name>
        <lei>549300KRHGOWQEB8SR45</lei>
        <title>Calvert Short-Duration Income Fund</title>
        <cusip>131582264</cusip>
        <identifiers>
          <isin value="US1315822643"/>
        </identifiers>
        <balance>701020.20100000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>11629925.13000000</valUSD>
        <pctVal>3.953847270905</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>
