27 CFR § 70.64 - Receipt for taxes.
The appropriate TTB officer must, upon request, issue a receipt for each tax payment made (other than a payment for stamps sold or delivered). In addition, an appropriate TTB officer or employee must issue a receipt for each payment of 1 dollar or more made in cash, whether or not requested. In the case of payments made by check, the canceled check is usually a sufficient receipt. No receipt shall be issued in lieu of a stamp representing a tax, whether the payment is in cash or otherwise.
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