<?xml version="1.0" encoding="UTF-8"?><edgarSubmission xmlns="http://www.sec.gov/edgar/nport" xmlns:com="http://www.sec.gov/edgar/common" xmlns:ncom="http://www.sec.gov/edgar/nportcommon" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sec.gov/edgar/nport eis_NPORT_Filer.xsd">
  <headerData>
    <submissionType>NPORT-P</submissionType>
    <isConfidential>false</isConfidential>
    <filerInfo>

      <filer>
        <issuerCredentials>
          <cik>0001065698</cik>
          <ccc>XXXXXXXX</ccc>
        </issuerCredentials>
      </filer>


      <seriesClassInfo>
        <seriesId>S000023371</seriesId>
        <classId>C000068441</classId>
        <classId>C000068440</classId>
      </seriesClassInfo>


    </filerInfo>
  </headerData>
  <formData>
    <genInfo>
      <regName>MFS VARIABLE INSURANCE TRUST III</regName>
      <regFileNumber>811-08879</regFileNumber>
      <regCik>0001065698</regCik>
      <regLei>549300QPPZUNGK3D0K61</regLei>
      <regStreet1>111 HUNTINGTON AVENUE</regStreet1>
      <regCity>BOSTON</regCity>
      <regStateConditional regCountry="US" regState="US-MA"/>
      <regZipOrPostalCode>02199</regZipOrPostalCode>
      <regPhone>617-954-5000</regPhone>
      <seriesName>MFS Conservative Allocation Portfolio</seriesName>
      <seriesId>S000023371</seriesId>
      <seriesLei>549300S8ONCJ2KJ3TE57</seriesLei>
      <repPdEnd>2024-12-31</repPdEnd>
      <repPdDate>2024-12-31</repPdDate>
      <isFinalFiling>N</isFinalFiling>
    </genInfo>
    <fundInfo>
      <totAssets>249842496.11</totAssets>
      <totLiabs>420529.31</totLiabs>
      <netAssets>249421966.80</netAssets>
      <assetsAttrMiscSec>0.00000000</assetsAttrMiscSec>
      <assetsInvested>0.00000000</assetsInvested>
      <amtPayOneYrBanksBorr>0.00000000</amtPayOneYrBanksBorr>
      <amtPayOneYrCtrldComp>0.00000000</amtPayOneYrCtrldComp>
      <amtPayOneYrOthAffil>0.00000000</amtPayOneYrOthAffil>
      <amtPayOneYrOther>0.00000000</amtPayOneYrOther>
      <amtPayAftOneYrBanksBorr>0.00000000</amtPayAftOneYrBanksBorr>
      <amtPayAftOneYrCtrldComp>0.00000000</amtPayAftOneYrCtrldComp>
      <amtPayAftOneYrOthAffil>0.00000000</amtPayAftOneYrOthAffil>
      <amtPayAftOneYrOther>0.00000000</amtPayAftOneYrOther>
      <delayDeliv>0.00000000</delayDeliv>
      <standByCommit>0.00000000</standByCommit>
      <liquidPref>0.00000000</liquidPref>
      <cshNotRptdInCorD>0.00000000</cshNotRptdInCorD>
      <isNonCashCollateral>N</isNonCashCollateral>
      <returnInfo>
        <monthlyTotReturns>
          <monthlyTotReturn classId="C000068441" rtn1="-2.11000000" rtn2="2.16000000" rtn3="-2.72000000"/>
          <monthlyTotReturn classId="C000068440" rtn1="-2.13000000" rtn2="2.18000000" rtn3="-2.64000000"/>
        </monthlyTotReturns>
        <othMon1 netRealizedGain="3303.12000000" netUnrealizedAppr="-5733747.56000000"/>
        <othMon2 netRealizedGain="646013.06000000" netUnrealizedAppr="4952944.37000000"/>
        <othMon3 netRealizedGain="68224.93000000" netUnrealizedAppr="-6898511.07000000"/>
      </returnInfo>
      <mon1Flow redemption="5186426.53000000" reinvestment="0.00000000" sales="139251.37000000"/>
      <mon2Flow redemption="4306656.31000000" reinvestment="0.00000000" sales="137193.34000000"/>
      <mon3Flow redemption="3521967.81000000" reinvestment="0.00000000" sales="124062.74000000"/>



    </fundInfo>
    <invstOrSecs>
      <invstOrSec>
        <name>MFS VIT Mid Cap Growth Series</name>
        <lei>DQS0BFT7TBCF2MYV2M94</lei>
        <title>MFS VIT Mid Cap Growth Series</title>
        <cusip>55273F670</cusip>
        <identifiers>
          <isin value="US55273F6705"/>
        </identifiers>
        <balance>1058448.79000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>9737728.85000000</valUSD>
        <pctVal>3.904118380161</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>MFS Variable Insurance Trust II - MFS International Growth Portfolio</name>
        <lei>8UVRTCWHDB4PB6VBAF77</lei>
        <title>MFS Variable Insurance Trust II - MFS International Growth Portfolio</title>
        <cusip>55274F463</cusip>
        <identifiers>
          <isin value="US55274F4634"/>
        </identifiers>
        <balance>316086.43000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>4991004.79000000</valUSD>
        <pctVal>2.001028559766</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>MFS VIT III Limited Maturity Portfolio</name>
        <lei>549300278SPJGR06E765</lei>
        <title>MFS VIT III Limited Maturity Portfolio</title>
        <cusip>86664T540</cusip>
        <identifiers>
          <isin value="US86664T5406"/>
        </identifiers>
        <balance>2756383.00000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>27839468.33000000</valUSD>
        <pctVal>11.16159442056</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>MFS Variable Insurance Trust - MFS Value Series</name>
        <lei>36LLVSYF4DQZKJ4FYT68</lei>
        <title>MFS Variable Insurance Trust - MFS Value Series</title>
        <cusip>55273F654</cusip>
        <identifiers>
          <isin value="US55273F6549"/>
        </identifiers>
        <balance>675757.93000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>14616644.03000000</valUSD>
        <pctVal>5.860207189257</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>MFS VIT III Global Real Estate Portfolio</name>
        <lei>549300YBJ6K5SOLBY732</lei>
        <title>MFS VIT III Global Real Estate Portfolio</title>
        <cusip>86664T300</cusip>
        <identifiers>
          <isin value="US86664T3005"/>
        </identifiers>
        <balance>386132.19000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>4815068.46000000</valUSD>
        <pctVal>1.930490935411</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>MFS Variable Insurance Trust II - MFS Government Securities Portfolio</name>
        <lei>TC07MNDC26S0HMWGJ177</lei>
        <title>MFS Variable Insurance Trust II - MFS Government Securities Portfolio</title>
        <cusip>55274F489</cusip>
        <identifiers>
          <isin value="US55274F4899"/>
        </identifiers>
        <balance>2267367.08000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>23966070.06000000</valUSD>
        <pctVal>9.608644486079</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>MFS VIT III Mid Cap Value Portfolio</name>
        <lei>549300DTS6NIQDMEIL78</lei>
        <title>MFS VIT III Mid Cap Value Portfolio</title>
        <cusip>86664T532</cusip>
        <identifiers>
          <isin value="US86664T5323"/>
        </identifiers>
        <balance>909027.65000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>9626602.77000000</valUSD>
        <pctVal>3.859564934679</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>MFS VIT III New Discovery Value Portfolio</name>
        <lei>549300X8U0YDKOFKNA72</lei>
        <title>MFS VIT III New Discovery Value Portfolio</title>
        <cusip>86664T441</cusip>
        <identifiers>
          <isin value="US86664T4417"/>
        </identifiers>
        <balance>291027.53000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2380605.22000000</valUSD>
        <pctVal>0.954448900609</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>MFS VIT II - International Intrinsic Value Portfolio</name>
        <lei>R8FUCFNPB06NBDV4PQ02</lei>
        <title>MFS VIT II - International Intrinsic Value Portfolio</title>
        <cusip>55274F455</cusip>
        <identifiers>
          <isin value="US55274F4550"/>
        </identifiers>
        <balance>167679.82000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>4995181.84000000</valUSD>
        <pctVal>2.002703251877</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>MFS Growth Series</name>
        <lei>IVAD1C1VZOLTR3W5MQ64</lei>
        <title>MFS Growth Series</title>
        <cusip>55273F100</cusip>
        <identifiers>
          <isin value="US55273F1003"/>
        </identifiers>
        <balance>176359.14000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12928888.70000000</valUSD>
        <pctVal>5.183540514042</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>MFS Variable Insurance Trust - Research Series</name>
        <lei>7AZFU5SPWYPK4FGVLU76</lei>
        <title>MFS Variable Insurance Trust - Research Series</title>
        <cusip>55273F308</cusip>
        <identifiers>
          <isin value="US55273F3082"/>
        </identifiers>
        <balance>434711.68000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>15471388.58000000</valUSD>
        <pctVal>6.202897354428</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>MFS Institutional Money Market Portfolio</name>
        <lei>5L2W638H85N8T1136O07</lei>
        <title>MFS Institutional Money Market Portfolio</title>
        <cusip>55291X109</cusip>
        <identifiers>
          <isin value="US55291X1090"/>
        </identifiers>
        <balance>6358967.81000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>6360239.60000000</valUSD>
        <pctVal>2.549991759587</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>MFS Variable Insurance Trust II - MFS Research International Portfolio</name>
        <lei>X2VCGKUPS3KBELF38X91</lei>
        <title>MFS Variable Insurance Trust II - MFS Research International Portfolio</title>
        <cusip>55274F356</cusip>
        <identifiers>
          <isin value="US55274F3560"/>
        </identifiers>
        <balance>728285.46000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12475529.84000000</valUSD>
        <pctVal>5.001776707984</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>MFS VIT III Inflation Adjusted Bond Portfolio</name>
        <lei>5493008RHGZT7FZTCC74</lei>
        <title>MFS VIT III Inflation Adjusted Bond Portfolio</title>
        <cusip>86664T359</cusip>
        <identifiers>
          <isin value="US86664T3591"/>
        </identifiers>
        <balance>3253494.25000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>25084440.68000000</valUSD>
        <pctVal>10.05702945968</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>MFS Total Return Bond Series</name>
        <lei>OBXD0C7FWK5N6XF1PG71</lei>
        <title>MFS Total Return Bond Series</title>
        <cusip>55273F878</cusip>
        <identifiers>
          <isin value="US55273F8784"/>
        </identifiers>
        <balance>3397936.90000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>39076274.30000000</valUSD>
        <pctVal>15.66673328790</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>MFS High Yield Portfolio</name>
        <lei>ZJO44YL9IRHSPRALW090</lei>
        <title>MFS High Yield Portfolio</title>
        <cusip>55274F471</cusip>
        <identifiers>
          <isin value="US55274F4717"/>
        </identifiers>
        <balance>2516656.71000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>12633616.66000000</valUSD>
        <pctVal>5.065157981907</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>MFS Variable Insurance Trust II - MFS Global Governments Portfolio</name>
        <lei>6UIE5ULN0F0W22N47U94</lei>
        <title>MFS Variable Insurance Trust II - MFS Global Governments Portfolio</title>
        <cusip>55274F539</cusip>
        <identifiers>
          <isin value="US55274F5391"/>
        </identifiers>
        <balance>2388179.26000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>20084587.55000000</valUSD>
        <pctVal>8.052453361537</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>MFS New Discovery Series</name>
        <lei>UL64BH8MFVUS63PN5829</lei>
        <title>MFS New Discovery Series</title>
        <cusip>55273F845</cusip>
        <identifiers>
          <isin value="US55273F8453"/>
        </identifiers>
        <balance>173181.53000000</balance>
        <units>NS</units>
        <curCd>USD</curCd>
        <valUSD>2391636.87000000</valUSD>
        <pctVal>0.958871786909</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>2025-01-15</ncom:dateSigned>
      <ncom:nameOfApplicant>MFS VARIABLE INSURANCE TRUST III</ncom:nameOfApplicant>
      <ncom:signature>James Byrne</ncom:signature>
      <ncom:signerName>James Byrne</ncom:signerName>
      <ncom:title>Assistant Treasurer</ncom:title>
    </signature>
  </formData>
</edgarSubmission>
