<TABLE> <S> <C>
<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
FINANCIAL STATEMENTS FOR ADC TELECOMMUNICATIONS, INC. AND SUBSIDIARIES FOR
THE SIX-MONTH PERIOD ENDED APRIL 30, 1999 AND IS QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<RESTATED>
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> OCT-31-1999
<PERIOD-START> NOV-01-1998
<PERIOD-END> APR-30-1999
<CASH> 171,528
<SECURITIES> 41,285
<RECEIVABLES> 358,811<F1>
<ALLOWANCES> 7,942
<INVENTORY> 215,759<F2>
<CURRENT-ASSETS> 856,216
<PP&E> 559,119
<DEPRECIATION> 265,948
<TOTAL-ASSETS> 1,465,442
<CURRENT-LIABILITIES> 336,082
<BONDS> 0
0
0
<COMMON> 27,216
<OTHER-SE> 1,088,352
<TOTAL-LIABILITY-AND-EQUITY> 1,465,442
<SALES> 860,885
<TOTAL-REVENUES> 860,885
<CGS> 452,776
<TOTAL-COSTS> 452,776
<OTHER-EXPENSES> 342,657
<LOSS-PROVISION> 2,307
<INTEREST-EXPENSE> 5,914
<INCOME-PRETAX> 64,285
<INCOME-TAX> 28,677
<INCOME-CONTINUING> 35,608
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> 35,608
<EPS-BASIC> 0.13
<EPS-DILUTED> 0.13
<FN>
<F1>AMOUNT IS NET OF ALLOWANCE FOR BAD DEBT AND RETURNS
<F2>AMOUNT IS NET OF OBSOLESCENCE RESERVES
</FN>
</TABLE>