Definition
An Importer Security Filing, often called ISF-10 or the "10+2", is a U.S. Customs and Border Protection requirement for ocean import shipments. The importer (or their agent) must electronically submit ten data elements about the shipment to CBP before the cargo is laden on a vessel destined for the United States.
Why it matters
ISF must be filed no later than 24 hours before the cargo is loaded onto the vessel at the foreign port. The ten fields are copied from the booking confirmation, commercial invoice, and packing list, which is why the filing step is slow and error-prone when those documents are read and re-typed by hand for every shipment.
The ten required data elements
The importer's ten fields are: seller, buyer, importer of record, consignee, manufacturer or supplier, ship-to party, country of origin, commodity HTS number, container stuffing location, and consolidator. The carrier's two elements ("plus 2") are the vessel stow plan and the container status messages. The importer is responsible for all ten importer fields. If any field is missing or incorrect at filing, the ISF is considered incomplete and subject to penalty.
When the 24-hour clock actually starts
The deadline is 24 hours before the cargo is laden aboard the vessel at the foreign port, not 24 hours before departure. The distinction matters when loading begins the day before the stated ETD. A pre-alert that arrives late, or that contains an incomplete manufacturer or HTS field, can push the filing past that cutoff even when the underlying documents arrived in time. A single late or inaccurate ISF exposes the importer to a penalty of up to $5,000 per violation under 19 CFR Part 149.
Why the reconcile step is where ISF filings break
Most ISF errors trace back to the data-gathering step before filing, not to a mistake in ACE. A manufacturer listed as a trading company on the commercial invoice, a country of origin that disagrees between the invoice and packing list, or an HTS code carried over from a prior shipment without checking the current schedule, each of these creates a filing the filer either catches and corrects or lets through. The ops team that reads source documents slowly, under time pressure, is the one that sends guesses to the filer. Automating the read step removes the time pressure and isolates the judgment to the reconcile step where it belongs.
TIO reads the pre-alert and pre-fills all ten ISF fields with a confidence score and source text per field, then queues the filing for your licensed filer to review and submit.
Learn more →Frequently asked questions
What are the 10 data elements required for an ISF filing?
The ten importer elements are: seller, buyer, importer of record, consignee, manufacturer or supplier, ship-to party, country of origin, commodity HTS-6 code, container stuffing location, and consolidator. The carrier adds two elements: the vessel stow plan and container status messages. All ten importer elements must reach CBP no later than 24 hours before the cargo is laden aboard the vessel at the foreign port of lading. Missing or inaccurate elements are each a separate violation, subject to a penalty of up to $5,000 under 19 CFR Part 149.
Who is responsible for filing the ISF?
The obligation rests on the importer of record. In practice, the importer's licensed customs broker or freight forwarder files on the importer's behalf using a registered ISF filer code. The party registered with CBP as the filer of record bears liability for late, inaccurate, or incomplete submissions. A freight forwarder that files ISF as a service must be registered as the ISF filer or file under the importer's filer code with written authorization.
What is the deadline to file ISF for an ocean import shipment?
CBP requires the ISF to be filed at least 24 hours before cargo is laden aboard the vessel at the foreign port of lading. The clock starts when loading begins, not when the vessel departs. On a China-origin shipment with a five-day transit, the ISF filing window typically opens when the booking confirmation arrives, roughly five to ten days before vessel loading. A filing submitted after the 24-hour cutoff is a late filing regardless of when the cargo arrives in the United States.