(a) Except as provided in paragraphs (g), (h), and (i) of this section, we will charge interest, penalties, and administrative costs on delinquent debts owed to the United States. These charges will continue to accrue until the debtor pays the debt in full or otherwise resolves the debt through compromise, termination, or an approved waiver.

(b) Interest. We will charge interest on delinquent administrative debts owed the agency as follows:

(1) Interest will accrue from the date of delinquency or as otherwise provided by law. For debts not paid by the date specified in the written demand for payment made under § 422.805, the date of delinquency is the date of mailing of the notice. The date of delinquency for an installment payment is the due date specified in the payment agreement.

(2) Unless a different rate is prescribed by statute, contract, or a repayment agreement, the rate of interest charged will be the rate established annually by the Treasury pursuant to 31 U.S.C. 3717. We may charge a higher rate if necessary to protect the rights of the United States, and the Commissioner has determined and documented a higher rate for delinquent debt is required to protect the Government's interests.

(3) Unless prescribed by statute or contract, the initial rate of interest charged will remain fixed for the duration of the indebtedness. A debtor who defaults on a repayment agreement may seek to enter into a new agreement. If we agree to a new agreement, we may require additional financial information and payment of interest at a new rate that reflects the Treasury rate in effect at the time the new agreement is executed or at a higher rate consistent with paragraph (b)(2) of this section. Interest will not be compounded. That is, we will not charge interest on the interest, penalties, or administrative costs required by this section, except as permitted by statute or contract. If, however, the debtor defaults on a previous repayment agreement, we will add charges that accrued but were not collected under the defaulted agreement to the principal of any new repayment agreement.

(c) Penalty. Unless otherwise established by contract, repayment agreement, or statute, we will charge a penalty pursuant to 31 U.S.C. 3717(e)(2) and 31 CFR 901.9 on the amount due on a debt that is delinquent for more than 90 days. This charge will accrue from the date of delinquency.

(d) Administrative costs. We will assess administrative costs incurred for processing and handling delinquent debts. We will base the calculation of administrative costs on actual costs incurred or a valid estimate of the actual costs. Calculation of administrative costs will include all direct (personnel, supplies, etc.) and indirect collection costs, including the cost of providing a hearing or any other form of administrative review requested by a debtor and any costs charged by a collection agency under § 422.837. We will assess these charges monthly or per payment period throughout the period that the debt is overdue. Such costs may also be in addition to other administrative costs if collection is being made for another Federal agency or unit.

(e) Cost of living adjustment. When there is a legitimate reason to do so, such as when calculating interest and penalties on a debt would be extremely difficult because of the age of the debt, we may increase an administrative debt by the cost of living adjustment in lieu of charging interest and penalties under this section. The cost of living adjustment is the percentage by which the Consumer Price Index for the month of June of the calendar year preceding the adjustment exceeds the Consumer Price Index for the month of June of the calendar year in which the debt was determined or last adjusted. We will manually compute such increases to administrative debts.

(f) Priority. When a debt is paid in partial or installment payments, amounts received will be applied first to outstanding penalties, second to administrative charges, third to interest, and last to principal.

(g) Waiver. (1) We will waive the collection of interest and administrative costs imposed pursuant to this section on the portion of the debt that is paid within 30 days after the date on which interest began to accrue. Excepting debt affected by fraud or other misconduct, we may extend this 30-day period on a case-by-case basis if we determine that such action is in the best interest of the Government or is otherwise warranted by equity and good conscience.

(2) We may waive interest, penalties, and administrative charges charged under this section, in whole or in part, without regard to the amount of the debt, based on:

(i) The criteria set forth at § 422.846 (b)(1) for the compromise of debts; or

(ii) A determination by the agency that collection of these charges is:

(A) Against equity and good conscience; or

(B) Not in the best interest of the United States.

(h) Review. (1) Except as provided in paragraph (h)(2) of this section, administrative review of a debt will not suspend the assessment of interest, penalties, and administrative costs. While agency review of a debt is pending, the debtor may either pay the debt or be liable for interest and related charges on the uncollected debt. When agency review results in a final determination that any amount was properly a debt and the debtor failed to pay the full amount of the disputed debt, we will collect from the debtor the amount determined to be due, and interest, penalties and administrative costs on the debt amount. We will calculate and assess interest, penalties, and administrative costs under this section starting from the date the debtor was first made aware of the debt and ending when the debt is repaid.

(2) Exception. Interest, penalties, and administrative cost charges will not be imposed on a debt for periods during which collection activity has been suspended under § 422.848(c)(1) pending agency review or consideration of waiver, if a statute prohibits collection of the debt during this period. This exception does not apply to interest, penalties, and administrative cost charges on debts affected by fraud or other misconduct unless a statute so requires.

(i) Common law or other statutory authority. We may impose and waive interest and related charges on debts not subject to 31 U.S.C. 3717 in accordance with the common law or other statutory authority.