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Rule 497(d)
File No. 333-95751
Supplement dated April 14, 2000 to the Prospectus dated February 17, 2000
Nuveen Unit
Trusts, Series 81
Nuveen Nasdaq 100 Index Portfolio, February 2000
The maximum sales charge for the Portfolio is a fixed dollar amount of $0.45 per
Unit. The maximum sales charge is reduced in accordance with the schedule
provided in the Prospectus. Previously, the maximum sales charge could not
exceed 5.5% of the Public Offering Price. Effective April 14, 2000,
notwithstanding anything to contrary in the Prospectus, the maximum sales charge
may not exceed 7.25% of the Public Offering Price.
