A Post Summary Correction, or PSC, is the electronic replacement of an ACE entry summary that an importer or broker files to fix errors before the entry liquidates, and it is the only way to correct an accepted entry summary while the entry is still open. It must be filed within 300 days of the date of entry, and no later than 15 days before the scheduled liquidation date, whichever comes first. Liquidation typically lands 314 days after entry. A PSC can correct classification, value, origin, free trade agreement claims, and Section 301 or 232 exclusions. Once the entry liquidates, the correction path is a protest, filed within 180 days of liquidation.
The PSC replaced the PEA, and the deadline has two parts
A PSC is the modern replacement for the old Post Entry Amendment, which CBP ended for ACE entry summaries effective September 22 2011, after creating the PSC as a test on June 24 2011. Fifteen years later it is still formally a test, run under 19 CFR 101.9(b), and modified through a series of Federal Register notices, the most recent published July 6 2026. The obligation behind it is not optional: under 19 USC 1484 and 1485, an importer who learns that information on an entry was wrong is required to correct it, and the trade, not CBP, is responsible for filing the correction.
The deadline has two parts, and the second one catches people. A PSC must be transmitted within 300 days of the date of entry, and no later than 15 days before the scheduled liquidation date, whichever date comes first, and ACE automatically rejects a PSC filed after it. Take an entry dated March 1: day 300 falls in late December, but on the standard 314-day liquidation cycle the 15-day cutoff falls on day 299, one day before the 300-day limit. Teams that build their calendar on 300 days find ACE rejecting a filing on day 292 because that particular entry was scheduled to liquidate early, and the rejection is automatic and not appealable as a filing error.
Related reading on this site: TariffWatch HQ and CBP Form 29 in Practice: The Notice of Action That Changes Your Rate cover the neighbouring problems in more depth.
What a PSC can and cannot change
A PSC can correct classification, value, origin, free trade agreement claims, additional duties such as Section 301 or 232, and even add missing lines. Most formal entry types are eligible, while informal entries are not, and the entry summary must be accepted, fully paid, unliquidated, and not under CBP review. A PSC cannot change the importer of record: that requires a CBP Form 3347, after which CBP amends ACE and the entry summary re-enters the cycle. Entry type can only be changed between type 01 and type 03, the consumption to antidumping or countervailing duty transition, not an arbitrary reclassification.
There are two narrow exceptions to the deadline. If the importer requested and CBP granted an extension of liquidation under 19 CFR 159.12, the 300-day limit falls away, but the PSC must still be filed at least 15 days before the new scheduled liquidation date. And for entries whose liquidation is suspended beyond 300 days, a PSC can be filed after day 300 if the entry carries a qualifying suspension basis, such as CVD suspend, ADD suspend, AD/CVD suspend, subject to EAPA, or subject to court injunction. Filing a PSC does not automatically delay liquidation, though CBP may extend or suspend it.
After the window closes, the protest is the only road
Once the PSC window closes, ACE rejects the correction, and the fix has to wait until the entry liquidates and then go through a protest. A protest is a different instrument from a correction: it contests a CBP decision rather than amending a declaration, and it must be filed in the ACE Protest Module within 180 days of the liquidation date. Miss that deadline and the refund is likely lost. The protest is the right tool for a belated exclusion claim or a valuation change, but it is slower, more formal, and more expensive than a PSC filed on time.
One carve-out matters in 2026. After the Supreme Court struck down the IEEPA tariffs on February 20 2026, CBP built a separate refund process called CAPE inside ACE, and it has told importers not to file PSCs to request IEEPA refunds. PSCs are still the right tool for other corrections, such as classification or valuation errors, and those should be filed before an entry goes on a CAPE declaration, because an entry accepted into CAPE can no longer take a PSC. The usable deadline is the earlier of entry plus 300 days and scheduled liquidation minus 15 days, and the only way to know which one governs an entry is to hold its scheduled liquidation date in the file, not to assume the standard cycle.
Frequently asked questions
What is a Post Summary Correction?
It is the electronic replacement of an ACE entry summary that an importer or broker files to fix errors before the entry liquidates. It is the only way to correct an accepted entry summary while the entry is still open, and it replaced the old Post Entry Amendment in 2011.
What is the deadline for filing a PSC?
Within 300 days of the date of entry, and no later than 15 days before the scheduled liquidation date, whichever comes first. Liquidation typically lands 314 days after entry, so the 15-day cutoff often arrives first, and ACE automatically rejects a late filing.
What can a PSC correct?
Classification, value, origin, free trade agreement claims, Section 301 or 232 exclusions, and missing lines. It cannot change the importer of record, which requires a CBP Form 3347, and entry type can only change between type 01 and type 03.
What happens after the PSC window closes?
The correction path becomes a protest, filed in the ACE Protest Module within 180 days of the liquidation date. A protest contests a CBP decision rather than amending a declaration, and missing the 180-day deadline usually means losing the refund.