Importers tend to treat entry as the end of the customs story: goods released, summary filed, duty paid. CBP treats liquidation as the end. Liquidation is the agency's final computation of duty on an entry, normally occurring around 314 days after entry unless CBP extends it or suspends it under court order or another authority. Until liquidation, the entry is still adjustable: the filer can amend it by post-summary correction, and CBP can revisit its own treatment. At liquidation the numbers harden, and the importer's remedy narrows to one instrument with one deadline: a protest under 19 USC 1514, filed within 180 days of liquidation, challenging the decisions the protest statute covers, classification, rate, value, and the rest of the listed grounds. A protest not filed in that window is not late in a forgivable sense. The entry stands as liquidated, the classification argument that would have won is permanently unavailable for that entry, and the same error sails on into the next hundred entries if nobody connects the two events.
Most entries liquidate unnoticed, which is the risk
Nobody receives a dramatic notification. Liquidation happens in the ordinary course, visible in ACE reports to importers and brokers who look, invisible to everyone else. For a one off entry that invisibility is harmless. For an importer running a deliberate classification position, a test case product, a product under a ruling request, or a known value dispute, an unnoticed liquidation converts a managed position into a closed file. The control is a watchlist: entries carrying live arguments get flagged at filing, their expected liquidation dates diarised, and someone owns checking ACE liquidation status for the flagged set on a monthly rhythm. It is an hour of clerical work standing in front of five and six figure arguments.
Related reading on this site: TariffWatch HQ and How to Read a Tariff Notice Without Getting the Date Wrong cover the neighbouring problems in more depth.
Corrections have a closing date too
The post-summary correction, the workhorse fix for entry errors, is generally available until liquidation approaches, commonly described as up to 300 days after entry or 15 days before scheduled liquidation, whichever comes first. That means the correction window and the liquidation clock are the same clock read from two directions. An importer who discovers a systematic classification error in month ten does not have until liquidation to fix the run of affected entries at leisure. Some of those entries are weeks from liquidating, and the correction queue should be worked in liquidation order, nearest deadline first, which is rarely the order the errors were discovered in.
A protest protects more than its own entry
Filing a protest on a liquidated entry does double duty. It preserves the argument for that entry, and if the issue is systemic, it creates the record around which the importer's broader position, ruling requests, prior disclosures, and corrections to unliquidated entries, gets organised. Courts and CBP both read patterns. An importer who protested the first liquidation and corrected the rest looks like a business managing a genuine dispute. An importer who let the first dozen liquidations pass silently and then discovered the issue looks like a business that found a refund opportunity, and the two files get different receptions for identical underlying merits.
Frequently asked questions
What is liquidation of a customs entry?
Liquidation is CBP's final determination of the duty owed on an entry, normally about 314 days after entry unless extended or suspended. Before liquidation an entry can be amended; after it, the amounts are final subject only to protest or other specific remedies.
How long do you have to file a customs protest?
A protest under 19 USC 1514 must generally be filed within 180 days after liquidation of the entry. The deadline is strict: a late protest leaves the liquidated classification, value, and rate decisions standing for that entry.
Until when can a post-summary correction be filed?
Generally until shortly before liquidation, commonly up to 300 days after entry or 15 days before the scheduled liquidation date, whichever is earlier. Importers fixing a run of entries should work in liquidation order, nearest deadline first.
How does an importer know an entry has liquidated?
Liquidation status is visible through ACE reports available to the importer and its broker. Importers with entries carrying live classification or value arguments should monitor status deliberately, since liquidations occur in the ordinary course without separate dramatic notice.