<TABLE> <S> <C>
<PAGE>
<ARTICLE> 5
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE BALANCE
SHEET AND INCOME STATEMENT OF TYCO INTERNATIONAL LTD. AS OF AND FOR THE FISCAL
YEAR ENDED SEPTEMBER 30, 1999 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-START> OCT-01-1998
<PERIOD-END> SEP-30-1999
<CASH> 1,762
<SECURITIES> 0
<RECEIVABLES> 4,846
<ALLOWANCES> 330
<INVENTORY> 2,849
<CURRENT-ASSETS> 11,146
<PP&E> 13,307
<DEPRECIATION> 5,984
<TOTAL-ASSETS> 32,344
<CURRENT-LIABILITIES> 9,125
<BONDS> 9,109
0
0
<COMMON> 338
<OTHER-SE> 12,031
<TOTAL-LIABILITY-AND-EQUITY> 32,344
<SALES> 22,497
<TOTAL-REVENUES> 22,497
<CGS> 14,433
<TOTAL-COSTS> 14,433
<OTHER-EXPENSES> 0
<LOSS-PROVISION> 142
<INTEREST-EXPENSE> 486
<INCOME-PRETAX> 1,705
<INCOME-TAX> 638
<INCOME-CONTINUING> 1,068
<DISCONTINUED> 0
<EXTRAORDINARY> (46)
<CHANGES> 0
<NET-INCOME> 1,022
<EPS-BASIC> 0.62
<EPS-DILUTED> 0.61
</TABLE>