18 CFR §382.103

1. (a)Annual charges assessed under this part must be paid within 45 days of the issuance of the bill by the Commission, unless a petition for waiver has been filed under § 382.105 of this part.
2. (b)Payment must be made by check, draft, or money order, payable to the United States Treasury.
3. (c)If payment is not made within 45 days of issuance of a bill, interest will be assessed. Interest will be computed in accordance with § 154.501(d) of this chapter, from the date on which the bill becomes delinquent.