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        <pctVal>7.320514858999</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>1528539.42000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>17165497.72000000</valUSD>
        <pctVal>4.380683433675</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>479375.58000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>7948047.03000000</valUSD>
        <pctVal>2.028364019636</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 Flexible Bond Fund</name>
        <lei>549300HDLJYKTU171023</lei>
        <title>Calvert Flexible Bond Fund</title>
        <cusip>13161X840</cusip>
        <identifiers>
          <isin value="US13161X8406"/>
        </identifiers>
        <balance>807371.36000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>11666516.18000000</valUSD>
        <pctVal>2.977327834711</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 Value Responsible Index Fund</name>
        <lei>5493005WGBW1GHF4CG37</lei>
        <title>Calvert US Large Cap Value Responsible Index Fund</title>
        <cusip>131618464</cusip>
        <identifiers>
          <isin value="US1316184647"/>
        </identifiers>
        <balance>889993.54000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>28604392.28000000</valUSD>
        <pctVal>7.299921588953</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>1406400.28000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12657602.48000000</valUSD>
        <pctVal>3.230255853844</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>86693.33000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>3985292.47000000</valUSD>
        <pctVal>1.017057878918</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>Morgan Stanley &amp; Co. LLC</name>
        <lei>549300BI6Y5SI6BYPB26</lei>
        <title>Morgan Stanley Institutional Liquidity Funds - Government Portfolio</title>
        <cusip>61747C707</cusip>
        <identifiers>
          <isin value="US61747C7074"/>
        </identifiers>
        <balance>2805606.68000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2805606.68000000</valUSD>
        <pctVal>0.715998737989</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>STIV</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>311091.05000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>11140170.32000000</valUSD>
        <pctVal>2.843002886673</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>199244.08000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>19187204.42000000</valUSD>
        <pctVal>4.896628685768</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 ULTRA BOND CBT JUN24</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Bloomberg Identifier" value="BBG01JD1QQY7"/>
        </identifiers>
        <balance>25.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>49184.50000000</valUSD>
        <pctVal>0.012552023125</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>CME Ultra Long Term U.S. Treasury Bond Futures</indexName>
                <indexIdentifier>WNM4 Comdty</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <expDate>2024-06-18</expDate>
            <notionalAmt>3175815.50000000</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>49184.50000000</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>552468.92000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>16817153.99000000</valUSD>
        <pctVal>4.291785131271</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>U.S. Treasury Inflation-Indexed Notes</title>
        <cusip>91282CEZ0</cusip>
        <identifiers>
          <isin value="US91282CEZ05"/>
        </identifiers>
        <balance>8569016.94000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>7774485.78000000</valUSD>
        <pctVal>1.984070699104</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2032-07-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>0.62500000</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>Chicago Board of Trade</name>
        <lei>549300EX04Q2QBFQTQ27</lei>
        <title>US 2YR NOTE (CBT) JUN24</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Bloomberg Identifier" value="BBG01JJ9YYW0"/>
        </identifiers>
        <balance>11.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>-1890.83000000</valUSD>
        <pctVal>-0.00048254514</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>CBOT 2 Year U.S. Treasury Notes Futures</indexName>
                <indexIdentifier>TUM4 Comdty</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <expDate>2024-06-28</expDate>
            <notionalAmt>2251218.97000000</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>-1890.83000000</unrealizedAppr>
          </futrDeriv>
        </derivativeInfo>
        <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>836930.37000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>20496424.74000000</valUSD>
        <pctVal>5.230745404107</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>786608.87000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>7755963.47000000</valUSD>
        <pctVal>1.979343753349</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>371332.10000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5789067.44000000</valUSD>
        <pctVal>1.477386338835</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>2024-04-25</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>
</edgarSubmission>
