31 CFR § 205.28 - How are interest payments exchanged?
(a) We offset the adjusted total State interest liability and the adjusted total Federal interest liability for each State to determine the net interest payable to or from each specific State. The payment of net interest and any Interest Calculation Costs, as set forth in § 205.27, for the most recently completed fiscal year must occur no later than March 31. We will notify a State of the final net interest liability. A State must submit a claim to receive payment.
(b) A State may appeal a decision by us on interest liabilities and interest calculation cost claims in accordance with § 205.31.
(c) If a State appeals the amount of interest payable in accordance with the provisions of § 205.31, payment must occur by March 31 for any portions not subject to the appeal.
(d) The Federal government will not be liable for interest on any payment of interest to a State.