Does CBP pay interest on IEEPA tariff refunds?

Yes. Under 19 USC § 1505(c), CBP must pay interest on any duties refunded as overpayments. Interest accrues from the date you deposited the duty until the date the refund is paid, at the rate established by the Treasury Department under 26 USC § 6621 (the same rate the IRS uses for tax overpayments). The interest portion is reported on Form 1099-INT.

What interest rate does CBP use for IEEPA refunds?

CBP uses the IRS overpayment rate published quarterly in a Revenue Ruling. For non-corporate taxpayers, the rate is the federal short-term rate plus 3 percentage points. For corporate overpayments, the rate is the federal short-term rate plus 2 percentage points (with a lower rate of federal short-term + 0.5% on the portion of the overpayment exceeding $10,000). Importers should look up the rate in effect for each calendar quarter their duties were on deposit with CBP.

Has CBP published official guidance on IEEPA refund interest calculation?

Not as of May 4, 2026. The April 28, 2026 Court of International Trade order in Princess Awesome v. CBP directed CBP to publish guidance on interest rate and calculation methodology by updating its IEEPA Duty Refunds FAQ. As of this writing, every FAQ entry on cbp.gov/trade/programs-administration/trade-remedies/ieepa-duty-refunds carries an 'Updated' timestamp of 4/10/2026, 4/15/2026, or 4/17/2026 — none have been updated since the court order. Importers should not delay filing CAPE Declarations waiting for this guidance.

Is the interest portion of my IEEPA refund taxable income?

Yes. The interest CBP pays on a duty refund is treated as ordinary interest income for federal tax purposes and is reported to the importer on Form 1099-INT. Consult your tax advisor for state treatment and for the correct period of recognition (cash vs. accrual). The principal — the duty refund itself — is generally not income; it reduces previously deducted duty expense, which may require an amended return or a current-year recapture entry depending on your accounting method.

How can I check whether CBP calculated the interest correctly?

Pull the CBP-issued payment notice and the ACE entry detail. Confirm three dates: (1) the duty deposit date (usually the entry summary payment date), (2) the liquidation/reliquidation date that triggered the refund, and (3) the actual disbursement date. Multiply the daily rate (annual rate ÷ 365) for each calendar quarter the duty was on deposit by the duty principal, then sum across quarters. Compare to the interest amount on your 1099-INT. Discrepancies of more than a few dollars warrant a written inquiry to your assigned CBP port.

How CBP Calculates Interest on Your IEEPA Refund (2026 Guide)

If you paid IEEPA tariffs between February 2025 and February 2026, CBP owes you interest on the refund, not just the principal. The legal authority is clear (19 USC § 1505(c)). The calculation rate is clear (the same quarterly rate the IRS uses for tax overpayments). What’s not clear, as of May 4, 2026, is CBP’s official methodology — because the agency still hasn’t published the guidance the Court of International Trade ordered it to.

This guide gives you the formula importers and CFOs can use today to estimate interest, verify CBP’s payment, and book the income correctly on Form 1099-INT.

The Legal Basis: 19 USC § 1505(c)

The interest provision is short and unambiguous:

“Interest assessed due to an underpayment of duties, fees, or interest shall accrue, at a rate determined by the Secretary of the Treasury, from the date the importer of record is required to deposit estimated duties… Interest paid by the United States on excess moneys deposited shall be paid at the same rate, from the date the importer of record deposits estimated duties… to the date of liquidation or reliquidation of the applicable entry or reconciliation.”

In plain English for IEEPA refunds:

Start date: the day you (or your broker) paid the IEEPA duty, typically the entry summary payment date.
End date: the date CBP liquidates or reliquidates the entry to remove the IEEPA charge — not the date the cash hits your bank account.
Rate: the IRS overpayment rate in effect for each quarter the money was on deposit.

That last point matters. If your IEEPA duty sat with CBP across five calendar quarters, you apply five different rates, one to each quarter’s portion of the principal-days outstanding.

The Rate: IRS Overpayment Rate (26 USC § 6621)

The Treasury Secretary doesn’t invent a new rate for customs refunds. He points to the existing IRS rate published every quarter in a Revenue Ruling.

Taxpayer type	Rate (annual)
Non-corporate (sole proprietors, LLCs taxed as partnerships, individuals)	Federal short-term rate + 3 percentage points
Corporate overpayment, principal ≤ $10,000	Federal short-term rate + 2 percentage points
Corporate overpayment, principal > $10,000 (portion over)	Federal short-term rate + 0.5 percentage point

To find the exact number for any quarter:

Search the IRS site for “Revenue Ruling [year]-[number] interest rates.”
Each Revenue Ruling lists rates for the next quarter (e.g., the rate published in early March applies to April–June).
Use the rate in effect for each quarter your IEEPA duty was on deposit. Do not annualize a single current rate across the whole period — the rate moves.

A Worked Example

Assume:

Importer: a US C-corporation
Entry summary payment date: April 15, 2025
IEEPA duty paid: $50,000
Reliquidation date (CBP removes IEEPA via CAPE): June 1, 2026
Days on deposit: 412 days

Because the principal is over $10,000, this importer applies the higher corporate rate (federal short-term + 2%) on the first $10,000 and the lower rate (federal short-term + 0.5%) on the $40,000 above $10,000, for each quarter.

A simplified calculation pattern (use the actual published rates for each quarter):

Quarter        Days     Rate      Interest on $10,000     Interest on $40,000
2025 Q2 (76d)  76       R1+2.0    $10,000 × R1 × 76/365   $40,000 × R2 × 76/365
2025 Q3 (92d)  92       R1+2.0    ...                     ...
2025 Q4 (92d)  92       R3+2.0    ...                     ...
2026 Q1 (90d)  90       R5+2.0    ...                     ...
2026 Q2 (62d)  62       R7+2.0    ...                     ...
                                  ─────────────           ─────────────
                                  Sum (= A)               Sum (= B)
                                                Total Interest = A + B

Build this in a spreadsheet. Use one row per (quarter × principal tier). Pull the IRS rate for each quarter from the Revenue Ruling published the prior month. The total is what CBP should pay you in interest, on top of the $50,000 principal.

Where CBP Has Not Yet Spoken (as of May 4, 2026)

The April 28, 2026 CIT order in Princess Awesome v. CBP directed CBP to publish guidance on the interest rate and calculation methodology by updating its IEEPA Duty Refunds FAQ. On May 4, 2026, every FAQ entry on that page still carries an “Updated” timestamp of 4/10/2026, 4/15/2026, or 4/17/2026 — meaning no update has been posted since the court order. The official CSMS RSS feed likewise contains no new CAPE or IEEPA messages between May 2 and May 4, 2026.

Practical implication: do not delay your CAPE Declaration waiting for CBP’s interest formula. The statutory rate and methodology are knowable from § 1505(c) and § 6621. File now, document the dates, recompute when the official guidance posts, and dispute any discrepancy in writing through your assigned port.

Three Dates That Drive the Math

When you receive your refund, immediately pull the supporting documents and confirm:

Duty deposit date: the date your entry summary payment cleared. Find this on the ACE entry summary detail or in your broker’s payment confirmation.
Liquidation / reliquidation date: the date CBP officially closed the entry without the IEEPA charge. This is the date interest stops accruing — not the disbursement date. Pull this from ACE Report ES-022 (Entry Summary Liquidation) or ES-701 (Reliquidation).
Disbursement date: the date the refund actually arrived in your ACH-enrolled account. This date is not used in the interest calculation, but you need it to confirm CBP closed out the matter correctly.

If your CAPE-driven refund moves principal-only and treats interest as a separate later disbursement, ask your broker or the CBP port for a written breakdown.

How to Read the Interest Line on Form 1099-INT

CBP issues a Form 1099-INT for the interest portion of your refund. The principal — the IEEPA duty refund itself — is not reported on a 1099 because it is a return of an overpayment, not income.

When the 1099-INT arrives (typically January following the year the interest was paid):

Box 1: total interest income from CBP for the calendar year. Confirm this matches the interest on every refund payment you received in that year.
Match it to your accounting records. If you booked interest receivable when CBP confirmed the refund but the cash arrived later, watch the year of recognition (cash-basis taxpayers report in the year received).
Interest is ordinary income. State tax treatment varies — confirm with your tax advisor.
The duty refund itself reduces previously expensed duty cost. For most importers, this requires either an amended return for the prior year (if material) or a current-year recapture entry. Discuss with your CPA.

Common Math Errors to Watch For

Based on how CBP has historically calculated overpayment interest on Section 232 and 301 refunds, watch for:

Wrong start date — CBP using the entry date instead of the deposit date. The deposit date governs.
Wrong end date — CBP using the disbursement date instead of the liquidation/reliquidation date. The end date is liquidation; using disbursement under-states the interest in the importer’s favor only if disbursement comes later than liquidation, which is the typical case. If you see the disbursement date used, you may be underpaid.
Single rate across the whole period — CBP applying one rate (often the most recent quarter) to the entire 14-month deposit period. The rate moves quarterly.
No corporate tier split — non-corporate importers should not see the corporate $10,000 split applied; corporate importers should see it.
Compounding vs. simple interest — § 6621 interest under federal tax law is compounded daily. Whether CBP compounds in practice for customs refunds has not been clearly stated; if your CBP-paid interest is materially below your simple-interest estimate, ask the port for the calculation method in writing.

Action Checklist

Build a spreadsheet with one row per (quarter × principal tier) for each entry.
Look up the IRS overpayment rate for each quarter from the relevant Revenue Ruling.
Estimate interest before the refund arrives so you have a benchmark.
When the refund disburses, pull ACE reports ES-022 and ES-701 to confirm liquidation/reliquidation dates.
Compare CBP’s interest payment against your estimate. Variance over a few dollars per entry warrants a written inquiry to your port.
When the 1099-INT arrives in January, reconcile Box 1 to your records before booking the income.
If your CFO or controller has not been briefed, share the Are IEEPA refunds taxable? CFO guide (coming soon) — interest treatment differs from principal treatment.

Why You Shouldn’t Wait for the CBP FAQ Update

The CIT-ordered FAQ update is overdue, but the statutory framework has been settled for decades. § 1505(c) plus § 6621 give you everything you need to estimate interest today. Filing CAPE Declarations now — and documenting the three dates above — protects you regardless of when CBP eventually publishes its methodology.

For the broader CAPE Phase 1 picture and the recent CIT rulings, see CAPE Phase 1 by the numbers — April 28 CIT order. For protest deadlines that run in parallel with CAPE, see How to file a protest for an IEEPA tariff refund.

Disclaimer: CAPE Portal Guide is not a law firm or tax advisor. The interest math above is a planning estimate based on public statutes and Revenue Rulings; final amounts depend on CBP’s calculation and your specific facts. For binding advice on tax treatment, accounting method, or disputing a CBP interest payment, consult a licensed customs attorney and a CPA. If you’d like an introduction to a vetted trade-law professional, request a free assessment.