QUICK ANSWER ISF filing, the Importer Security Filing, is advance data CBP requires for ocean imports, submitted at least 24 hours before the cargo is loaded on the vessel at origin. It is called 10+2 because the importer provides ten data elements and the carrier provides two. Miss the deadline, or file it late, wrong, or incomplete, and the penalty is $5,000 per violation.
The ISF filing is the first deadline in an ocean import and one of the easiest to fail expensively. It has nothing to do with your goods clearing customs later; it is a security filing due before the container even sails. This guide covers what it contains, the 24-hour rule, the $5,000 penalty, and how to keep it off your invoice.
The Importer Security Filing and why it exists
The Importer Security Filing is a set of advance data that CBP requires for ocean cargo bound for the United States, introduced under the SAFE Port Act to screen shipments for risk before they load. It applies to ocean freight only, not air, and it is separate from the customs entry that clears the goods on arrival. In short, ISF is about security screening before departure; the entry is about admission and duty after arrival.
The 24-hour deadline
The ISF must be submitted to CBP at least 24 hours before the cargo is loaded onto the vessel at the origin port. That timing is the trap: the deadline lands at origin, before the goods are even on the water, so the data has to be gathered from your supplier early. A container that loads without a valid ISF on file is already in violation, regardless of what happens at the US end.
The 10+2 data elements
The "10+2" name comes from who provides what: ten elements from the importer and two from the ocean carrier.
The ISF 10+2 data elements
| Provided by | Elements |
|---|---|
| Importer (10) | Seller, buyer, importer of record number, consignee number, manufacturer or supplier, ship-to party, country of origin, HTS number, container stuffing location, consolidator |
| Carrier (2) | Vessel stow plan, container status messages |
Several of these tie straight to other customs data, the HTS number and the country of origin especially, so an ISF built on accurate shipment data is also a head start on a clean entry.
The $5,000 penalty
CBP can assess $5,000 for each ISF violation, and the violations are defined broadly: a late filing, an inaccurate one, an incomplete one, or a failure to withdraw or update one. Because a single shipment can breach on more than one ground, the exposure on one container can climb past a single $5,000 hit.
TAKEAWAY The ISF penalty is $5,000 per violation, and it is entirely avoidable. It is not a duty or a market cost; it is a paperwork deadline. Every ISF fine is a shipment where the supplier data was gathered too late or filed wrong, which is exactly the failure a managed filing prevents.
Who files the ISF and answers for it
The importer of record is legally responsible for the ISF, even when someone files it on their behalf. In practice the importer authorizes its freight forwarder or customs broker to prepare and submit the filing, using data collected from the supplier. The responsibility for accuracy still sits with the importer, which is why the data-gathering step, not the submission itself, is where filings succeed or fail.
ISF vs the customs entry
These are two different filings at two different times, and confusing them is common. The ISF is a security filing due 24 hours before loading at origin. The customs entry is the classification-and-duty filing made by a licensed broker around arrival to clear the goods. One protects the border before departure; the other admits the goods and collects duty after arrival. Both are part of the same customs clearance chain, but they are not the same document.
Keeping ISF penalties off your invoice
The fix is upstream and simple in principle: collect the ten data elements from your supplier before the cargo is booked to load, file early rather than at the deadline, and update the filing if anything changes. The failures are almost always timing, a supplier who sends the stuffing location or manufacturer details too late, so the practical safeguard is a process that requests ISF data at booking, not at loading.
How Platton files ISF on time
The ISF is a deadline that rewards a process and punishes a scramble. Platton runs it as part of the shipment, before the container loads.
Supplier data requested at booking
We request the ten ISF elements from your supplier when the shipment is booked, not when it is ready to load, so the 24-hour deadline is never the moment you start gathering data.
Filed early, through the shipment file
The ISF is filed well ahead of loading and kept consistent with the entry data, so the same accurate information flows into customs clearance on arrival.
Updated when the shipment changes
If a detail changes before loading, we update the filing, which is one of the violation grounds importers most often miss on their own.
One owner across the deadlines
One coordinator watches the ISF deadline, the entry, and the release together on the China to USA lane, so no clock starts unnoticed.
Get an import quote with ISF filing handled
Common Questions About ISF Filing
What is the Importer Security Filing?
It is advance data CBP requires for ocean imports to the US, submitted before the cargo loads at origin so shipments can be screened for risk. It is known as 10+2 because the importer provides ten data elements and the carrier two. The ISF is a security filing, separate from the customs entry that clears the goods and collects duty when they arrive.
When is the ISF due?
At least 24 hours before the cargo is loaded onto the vessel at the origin port. The deadline falls at origin, before the container is on the water, which is why the supplier data has to be gathered early. A shipment that loads without a valid ISF on file is already in violation, no matter how smoothly the rest of the import goes.
How much is the ISF penalty?
CBP can assess $5,000 for each ISF violation, and the grounds are broad: filing late, filing inaccurate or incomplete data, or failing to update or withdraw a filing. Because one shipment can violate on more than one ground, the total on a single container can exceed $5,000. The penalty is entirely avoidable with accurate, on-time data.
Who is responsible for filing the ISF?
The importer of record is legally responsible, even when a forwarder or broker files it for them. The importer authorizes an agent to prepare and submit the ISF using supplier data, but accountability for accuracy stays with the importer. That is why the reliable safeguard is a process that collects the ten data elements from the supplier at booking, not at the last minute.
Is the ISF the same as customs clearance?
No. The ISF is a security filing due 24 hours before loading at origin, while customs clearance is the entry a licensed broker files around arrival to classify the goods, assess duty, and get them released. They are two separate filings at two different points in the shipment. Both matter, but only the entry clears your goods, and only the ISF carries the 24-hour deadline.
Related Customs Guides
How US import customs clearance works: where the ISF sits in the full process.
HTS and HS codes: one of the ten ISF data elements.
Country of origin and USMCA rules: one more of the ten data elements, and a duty driver in its own right.
