WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000741375
<NAME> MAS FUNDS
<SERIES>
<NUMBER> 131
<NAME> CASH RESERVES PORTFOLIO, INVESTMENT CLASS
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-2000
<PERIOD-START> OCT-01-1999
<PERIOD-END> SEP-30-2000
<INVESTMENTS-AT-COST> 117,826
<INVESTMENTS-AT-VALUE> 117,826
<RECEIVABLES> 667
<ASSETS-OTHER> 13
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 118,506
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 1,016
<TOTAL-LIABILITIES> 1,016
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 117,477
<SHARES-COMMON-STOCK> 1,977
<SHARES-COMMON-PRIOR> 919
<ACCUMULATED-NII-CURRENT> 13
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 117,490
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 7,554
<OTHER-INCOME> 0
<EXPENSES-NET> (401)
<NET-INVESTMENT-INCOME> 7,153
<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 7,153
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (84)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 14,600
<NUMBER-OF-SHARES-REDEEMED> (13,627)
<SHARES-REINVESTED> 84
<NET-CHANGE-IN-ASSETS> (39,939)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 12
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 312
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 460
<AVERAGE-NET-ASSETS> 124,972
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.056
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> (0.056)
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.52
</TABLE>
