<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000917286
<NAME> Fidelity Hereford Street Trust
<SERIES>
<NUMBER> 21
<NAME> Spartan U.S. Government Money Market Fund
<MULTIPLIER> 1,000
<S>
<C>
<PERIOD-TYPE>
6-MOS
<FISCAL-YEAR-END>
APR-30-2001
<PERIOD-END>
OCT-31-2000
<INVESTMENTS-AT-COST>
780,506
<INVESTMENTS-AT-VALUE>
780,506
<RECEIVABLES>
24,237
<ASSETS-OTHER>
0
<OTHER-ITEMS-ASSETS>
0
<TOTAL-ASSETS>
804,743
<PAYABLE-FOR-SECURITIES>
44,929
<SENIOR-LONG-TERM-DEBT>
0
<OTHER-ITEMS-LIABILITIES>
1,504
<TOTAL-LIABILITIES>
46,433
<SENIOR-EQUITY>
0
<PAID-IN-CAPITAL-COMMON>
758,436
<SHARES-COMMON-STOCK>
758,436
<SHARES-COMMON-PRIOR>
815,782
<ACCUMULATED-NII-CURRENT>
0
<OVERDISTRIBUTION-NII>
0
<ACCUMULATED-NET-GAINS>
(126)
<OVERDISTRIBUTION-GAINS>
0
<ACCUM-APPREC-OR-DEPREC>
0
<NET-ASSETS>
758,310
<DIVIDEND-INCOME>
0
<INTEREST-INCOME>
25,935
<OTHER-INCOME>
0
<EXPENSES-NET>
1,772
<NET-INVESTMENT-INCOME>
24,163
<REALIZED-GAINS-CURRENT>
(3)
<APPREC-INCREASE-CURRENT>
0
<NET-CHANGE-FROM-OPS>
24,160
<EQUALIZATION>
0
<DISTRIBUTIONS-OF-INCOME>
24,163
<DISTRIBUTIONS-OF-GAINS>
0
<DISTRIBUTIONS-OTHER>
0
<NUMBER-OF-SHARES-SOLD>
205,375
<NUMBER-OF-SHARES-REDEEMED>
285,680
<SHARES-REINVESTED>
22,959
<NET-CHANGE-IN-ASSETS>
(57,349)
<ACCUMULATED-NII-PRIOR>
0
<ACCUMULATED-GAINS-PRIOR>
(123)
<OVERDISTRIB-NII-PRIOR>
0
<OVERDIST-NET-GAINS-PRIOR>
0
<GROSS-ADVISORY-FEES>
1,788
<INTEREST-EXPENSE>
0
<GROSS-EXPENSE>
1,789
<AVERAGE-NET-ASSETS>
788,671
<PER-SHARE-NAV-BEGIN>
1.000
<PER-SHARE-NII>
.031
<PER-SHARE-GAIN-APPREC>
0
<PER-SHARE-DIVIDEND>
.031
<PER-SHARE-DISTRIBUTIONS>
0
<RETURNS-OF-CAPITAL>
0
<PER-SHARE-NAV-END>
1.000
<EXPENSE-RATIO>
45
</TABLE>
