27 CFR § 479.161
National Firearms Act stamps
April 24, 2020
“National Firearms Act” stamps evidencing payment of the transfer tax or tax on the making of a firearm are maintained by the Director. The remittance for purchase of the appropriate tax stamp shall be submitted with the application. Upon approval of the application, the Director will cause the appropriate tax to be paid by affixing the appropriate stamp to the application.
[T.D. ATF-270, 53 FR 10511, Mar. 31, 1988]