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26 U.S. Code § 7504 - Fractional parts of a dollar

The Secretary may by regulations provide that in the allowance of any amount as a credit or refund, or in the collection of any amount as a deficiency or underpayment, of any tax imposed by this title, a fractional part of a dollar shall be disregarded, unless it amounts to 50 cents or more, in which case it shall be increased to 1 dollar.

Editorial Notes
Amendments

1976—Pub. L. 94–455 struck out “or his delegate” after “Secretary”.