27 CFR §46.233

1. (a)Electronic funds transfer. If the dealer pays any other excise taxes collected by TTB by electronic funds transfer, then the dealer must also send the payment for the floor stocks tax by an electronic funds transfer. Other dealers may voluntarily elect to pay the floor stocks tax by electronic funds transfer. Electronic funds transfers of floor stocks tax must be received on or before July 31, 2009.
2. (b)Check or money order. Dealers not paying floor stocks tax by electronic fund transfer must pay by a check or money order sent with Form 5000.28T09.