Getting overpaid duty back

Duty overpayment is common and quietly expensive. The three usual causes: a code that carried a higher rate than the correct one, an FTA preference you were eligible for but didn't claim, and — in 2026 specifically — duties you paid under a tariff a court later voided. Each has a different recovery path, and each path has a clock. Miss the clock and the money is gone regardless of how right you were.

First, the two-stage life of an entry

An entry isn't final the day it clears. It stays open, then liquidates — CBP's final calculation of what was owed — typically about 314 days after entry. The instrument you use depends on which side of liquidation you're on:

Post-Summary Correction (PSC) — the clean path

If the entry hasn't liquidated yet, a PSC lets you amend the entry summary directly — change the HTS code, correct the value, add the FTA claim you missed. CBP re-liquidates on the corrected figures and refunds the difference. This is the least adversarial route: you're fixing your own filing before it's final, not contesting CBP's decision. Most code-correction and missed-claim refunds should go this way if you catch them in time.

§514 Protest — after liquidation

Once the entry has liquidated, the PSC window is closed and your route is a formal protest under 19 U.S.C. §514, filed within 180 days of liquidation. A protest contests the classification, rate, or amount CBP finalized. It's more formal — you're now arguing CBP got it wrong — and it's exactly where a written, precedent-cited classification analysis earns its keep: the protest has to substantiate the code you say is correct, with the rulings and GRI reasoning behind it. A bare assertion doesn't win a protest; a documented analysis does.

The missed FTA claim (§1520(d))

Specific to free-trade agreements including KORUS: if your goods were eligible for a preference you didn't claim at entry, you can file a post-importation claim within one year of importation to recover the duty — and, for KORUS, the exempt MPF. You'll need the certification of origin and a rule-of-origin analysis to back it. This is the recovery path for the "we never claimed KORUS" situation from the KORUS guide.

The 2026 special case: struck-down tariff refunds

Two policy events opened refund pools worth watching this year:

• IEEPA reciprocal tariffs — voided. The Supreme Court struck these down in February 2026, creating a refund pool estimated around $166 billion for duties paid on entries roughly between August 2025 and February 2026. The refund mechanics are still being worked out — but eligibility turns on your entry records. If you paid these, the question is whether your ACE entry data supports the claim.
• Section 122 surcharge — under litigation. A court ruled against the balance-of-payments surcharge in 2026; a stay kept it collecting pending appeal. If the appeal fails, surcharge paid in the interim could become refundable — another reason to keep clean records now.

Worked example: the refund on one over-classified entry

Say a $10,000 LED mask was entered under the 7% textile line (6307.90.98) when the correct line was the 2.6% electrical line (8543.70.98), Korean origin, KORUS never claimed. What's recoverable via a PSC before liquidation:

The Section 122 surcharge isn't in the recoverable column here because it applies to both the wrong and the right code — the refund comes from the classification fix and the FTA claim, not the surcharge. Across a year of misfiled entries, this is the number that funds a correction project many times over.