PSC or PEA: Choosing the Right Correction After Entry Summary

A PSC, post summary correction, amends an entry summary that has been filed but not yet liquidated. A PEA, post entry amendment, is the older paper rooted process for correcting errors discovered in a narrower set of circumstances, and in the ACE era most corrections that importers argue about belong in a PSC while the entry is still open. The practical confusion is timing and error class. Clerical errors, classification changes, value adjustments, and Chapter 99 line corrections on an unliquidated entry are PSC territory, filed in ACE against the entry summary, with duty recalculated on the corrected figures. Once liquidation occurs, neither instrument applies, and the routes become protest under 19 USC 1514 for contestable decisions or a prior disclosure where a material violation is involved. Teams lose corrections by filing the right fix in the wrong window, discovering at month twelve a classification error that a PSC would have handled at month three.

The window is the first decision

Before classifying the error, establish the entry's status: filed, in review, liquidated, or under an extension of liquidation. CBP can extend liquidation, and entries subject to antidumping or countervailing duty orders routinely sit unliquidated far longer than standard entries, which quietly keeps the PSC window open for importers who check. The monthly habit that pays is an open entry report aged by entry date, reviewed against the classification worksheet and the commercial documents, so errors surface while every instrument is still available. The importer who learns an entry's status for the first time when they go to correct it has built the discovery process backwards.

Note the trap at the other end: an entry can liquidate while a correction is being prepared. Build the correction file to filing readiness, documents assembled, broker instructed, before the expected liquidation date on the report, not after a meeting about it. Liquidation does not send a warning letter timed to your convenience.

Related reading on this site: TariffTrack HQ and Tariff Change Alerts Your Classification Team Will Read cover the neighbouring problems in more depth.

Error class decides the mechanics

Within the PSC window, sort the error before filing. A transposed digit in a value, a quantity keyed from the wrong packing list line, a misspelled name: clerical, documented with the source paperwork, corrected cleanly. A classification judgment that changed on review, a value that excluded a dutiable assist, an origin claim that sourcing no longer supports: substantive, and the correction file needs the reasoning, not just the new figure, because these are the corrections CBP may examine and the ones that implicate reasonable care under 19 USC 1484. A pattern of the same substantive error across many entries is a different conversation again, and it belongs with counsel and a broker before it belongs in a stack of PSCs, because the pattern, not the individual entry, is what an audit will price.

Chapter 99 corrections deserve special care. A missing Section 301 line or a wrong 9903 subheading changes the duty by the full additional rate, and correcting it upward is a bill the importer should self deliver through the PSC rather than have delivered by a CF 28 or a notice of action. The file will be read either way. Choose who writes the first version.

Keep the correction log as an audit asset

Log every correction with entry number, error class, root cause, and the instruction change that followed. Importers treat the log as housekeeping. On audit it is the reasonable care evidence, the document that shows errors were found by a system, corrected through the right instrument, and fed back into the broker's instructions so the same error stopped recurring. A correction log with root causes that repeat unchanged for a year shows the opposite, and auditors can read. The log is short, monthly, and boring, like every control that actually works.

Frequently asked questions

What is the difference between a PSC and a PEA?

A post summary correction amends a filed but unliquidated entry summary in ACE and covers classification, value, quantity, and reporting line corrections. Post entry amendment is the older process for a narrower set of corrections. Most modern entry summary corrections belong in a PSC while the entry remains open.

What happens after an entry liquidates?

The correction routes change. Contestable CBP decisions go through a protest under 19 USC 1514 within the protest window, and material violations are handled through a prior disclosure. Neither a PSC nor a PEA can amend a liquidated entry.

Can a PSC correct a missing Section 301 Chapter 99 line?

Yes, while the entry is unliquidated, a PSC can add or correct Chapter 99 reporting lines, with duty recalculated on the corrected entry. Finding and self correcting the omission is materially better than having it found on review.

How should importers find errors before liquidation?

Run a scheduled review of open entries against invoices and classification worksheets, aged by entry date, looking for repeated patterns such as the same product under two codes or a missing additional duty line. A monthly cadence catches most errors while correction is still routine.