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        </identifiers>
        <balance>1861341.18400000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>16752070.66000000</valUSD>
        <pctVal>7.286755219386</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 Bond Fund</name>
        <lei>549300T75TF7NTCFI791</lei>
        <title>Calvert Bond Fund</title>
        <cusip>131582322</cusip>
        <identifiers>
          <isin value="US1315823229"/>
        </identifiers>
        <balance>4017723.10500000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>67578102.63000000</valUSD>
        <pctVal>29.39487911970</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 CASH RESERVES FUND CALVERT CASH RESERVES FUND</name>
        <lei>N/A</lei>
        <title>CALVERT CASH RESERVES FUND CALVERT CASH RESERVES FUND</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="966PLJ904"/>
        </identifiers>
        <balance>7780147.79000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>7780147.79000000</valUSD>
        <pctVal>3.384180598745</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>EC</assetCat>
        <issuerCat>RF</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</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>912810RL4</cusip>
        <identifiers>
          <isin value="US912810RL44"/>
        </identifiers>
        <balance>3175611.48000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>3890942.07000000</valUSD>
        <pctVal>1.692467934999</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2045-02-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>0.75000000</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>United States Treasury</name>
        <lei>254900HROIFWPRGM1V77</lei>
        <title>United States Treasury Inflation Indexed Bonds</title>
        <cusip>9128285W6</cusip>
        <identifiers>
          <isin value="US9128285W63"/>
        </identifiers>
        <balance>5407160.88000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>6166874.72000000</valUSD>
        <pctVal>2.682444902799</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>0.88000000</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 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>1384923.39100000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>13627646.17000000</valUSD>
        <pctVal>5.927704334145</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>13162A708</cusip>
        <identifiers>
          <isin value="US13162A7081"/>
        </identifiers>
        <balance>745907.00900000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>16037000.69000000</valUSD>
        <pctVal>6.975716665294</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>9128284H0</cusip>
        <identifiers>
          <isin value="US9128284H06"/>
        </identifiers>
        <balance>3348170.49000000</balance>
        <units>PA</units>
        <curCd>USD</curCd>
        <valUSD>3485232.97000000</valUSD>
        <pctVal>1.515994055323</pctVal>
        <payoffProfile>Long</payoffProfile>
        <assetCat>DBT</assetCat>
        <issuerCat>UST</issuerCat>
        <invCountry>US</invCountry>
        <isRestrictedSec>N</isRestrictedSec>

        <fairValLevel>2</fairValLevel>
        <debtSec>
          <maturityDt>2023-04-15</maturityDt>
          <couponKind>Fixed</couponKind>
          <annualizedRt>0.63000000</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 Opportunities Fund</name>
        <lei>549300125QOYCBC7IB51</lei>
        <title>Calvert International Opportunities Fund</title>
        <cusip>131649758</cusip>
        <identifiers>
          <isin value="US1316497585"/>
        </identifiers>
        <balance>360250.78200000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>5745999.97000000</valUSD>
        <pctVal>2.499374323436</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 High Yield Bond Fund</name>
        <lei>549300CCIV46L1T22Z08</lei>
        <title>Calvert High Yield Bond Fund</title>
        <cusip>131582439</cusip>
        <identifiers>
          <isin value="US1315824391"/>
        </identifiers>
        <balance>177508.11100000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>4514031.26000000</valUSD>
        <pctVal>1.963497021464</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) SEP20 XCBT 20200930</title>
        <cusip>000000000</cusip>
        <identifiers>
          <other otherDesc="Internal Identifier" value="ADI1HVCQ4"/>
        </identifiers>
        <balance>73.00000000</balance>
        <units>NC</units>
        <curCd>USD</curCd>
        <valUSD>24627.28000000</valUSD>
        <pctVal>0.010712285347</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>FVU0 Comdty</indexIdentifier>
              </indexBasketInfo>
            </descRefInstrmnt>
            <expDate>2020-09-30</expDate>
            <notionalAmt>9154552.44000000</notionalAmt>
            <curCd>USD</curCd>
            <unrealizedAppr>24627.28000000</unrealizedAppr>
          </futrDeriv>
        </derivativeInfo>
        <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>40672.01800000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>1103025.13000000</valUSD>
        <pctVal>0.479789889039</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>2020-07-31</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>
