If you are importing goods into the United States by ocean, the Importer Security Filing is the first compliance step that has to go right, and it happens weeks before your container ever touches an American dock. On US-bound ocean bookings our compliance desk at GetTransport.com coordinates the ISF alongside the booking itself, because the data has to be locked in long before the vessel sails. This guide walks through what the filing is, the twelve data points behind the "10+2" name, the deadline that trips up new importers, and the penalties for getting it wrong.
What the ISF "10+2" actually is
The Importer Security Filing, universally shortened to ISF or the "10+2" rule, is a mandatory electronic submission that CBP requires for ocean cargo bound for the United States. According to CBP, the rule grew out of the SAFE Port Act and was published as a final rule in November 2008. It took effect on January 26, 2009, followed by a twelve-month period of restrained enforcement that ended on January 26, 2010. CBP then tightened its approach in stages, and the penalty regime became much harder a few years after that.
The nickname is literal. The importer is responsible for ten data elements, and the ocean carrier supplies two more. Ten plus two. The purpose is risk assessment: CBP uses the filing to screen shipments for security threats before loading, rather than after the box has already crossed the ocean. It is a security program first and a trade program second.
The 12 data elements at a glance
Here is the full set. The ten importer elements are the ones you and your broker control; the two carrier elements are filed by the steamship line.
| Party responsible | Data element |
|---|---|
| Importer (1) | Seller (owner) name and address |
| Importer (2) | Buyer (owner) name and address |
| Importer (3) | Importer of record number or FTZ applicant ID |
| Importer (4) | Consignee number(s) |
| Importer (5) | Manufacturer (supplier) name and address |
| Importer (6) | Ship-to party name and address |
| Importer (7) | Country of origin |
| Importer (8) | Commodity HTSUS number (minimum 6 digits) |
| Importer (9) | Container stuffing location |
| Importer (10) | Consolidator (stuffer) name and address |
| Carrier (+1) | Vessel stow plan |
| Carrier (+2) | Container status messages (CSM) |
A useful nuance many first-time importers miss: not every element carries the same deadline. CBP treats four of the ten as flexible. You can submit your best available data for the manufacturer, ship-to party, country of origin, and HTSUS number at the initial deadline, then update them as firmer information arrives. The container stuffing location and the consolidator can be supplied later too, though no later than 24 hours before the vessel arrives in the US.
When must the ISF be filed?
This is the single most misunderstood part of the rule. The importer's ten elements must be transmitted to CBP no later than 24 hours before the cargo is laden aboard the vessel at the foreign port. Not 24 hours before US arrival. Twenty-four hours before loading overseas.
In practice that means your filing is often locked weeks ahead of the ship reaching an American port, because ocean transits from Asia or the Gulf can run two to four weeks. The carrier's two elements follow a different clock: the vessel stow plan is due no later than 48 hours after departure from the last foreign port, and container status messages flow as events happen. If you are new to ocean freight, our overview of customs clearance essentials for importers is a good companion read.
Who files the ISF, and who is on the hook
The legally responsible party is the "ISF Importer," which CBP defines as the party causing the goods to arrive in the US by vessel. For most shipments that is the importer of record, the owner, the purchaser, or the consignee. That party carries the liability whether or not it does the actual keystrokes.
Almost nobody files it themselves. In the vast majority of cases a licensed customs broker or a forwarder with in-house brokerage transmits the ISF on the importer's behalf, using a valid power of attorney and an ISF bond. That arrangement is normal and encouraged. One point worth correcting, though: delegating the filing does not delegate the liability. If the broker files late or transposes an HTSUS code, CBP still looks to the ISF Importer for the penalty. The paperwork moves; the responsibility does not.
Penalties: liquidated damages and how they are mitigated
CBP enforces the ISF through liquidated damages, which are contractual penalties tied to your customs bond rather than criminal fines. According to CBP's penalty guidelines, the standard assessment is $5,000 per violation for an ISF that is late, inaccurate, incomplete, or never withdrawn when a shipment is cancelled. Because a single shipment can breach the rule in more than one way, for example filed both late and with wrong data, total exposure on one shipment can reach $10,000.
Enforcement has hardened in stages. The soft milestone was 2010, when the flexible period ended. The harder one landed on July 9, 2013, when CBP moved into the liquidated-damages phase in earnest, began issuing "Do Not Load" messages to foreign ports, and started placing ACE cargo holds on non-compliant shipments. Day to day, though, much enforcement rests on local port discretion. Ports decide what counts as "significantly late" and will often warn first. One port might assess damages only when an ISF is more than 10 days late or filed under 48 hours before arrival, while another draws a stricter line.
The good news is that the opening number is rarely the final number. CBP's guidelines allow an importer to petition for mitigation, and where the agency finds that no law-enforcement goal was compromised, a claim is typically cancelled on payment of an amount between $1,000 and $2,000, depending on mitigating and aggravating factors. Beyond the dollars, a bad ISF invites operational pain: intensive CBP examinations and terminal holds that stall the whole shipment. Delay costs frequently exceed the penalty itself.
How our desk keeps ISF filings clean
The ISF misses we see are almost always data problems, not filing-mechanism problems. A supplier changes the factory of manufacture and nobody updates the ISF. The commercial invoice lists a six-digit HTS that does not match the entry. A container is re-stuffed at a different location than the booking assumed. None of those are exotic. They are ordinary supply-chain drift, and they become penalties when nobody reconciles the data before the deadline.
A few practices we lean on, and that we recommend to any importer running US ocean lanes:
- File early, update deliberately. Submit as soon as the booking is firm, then use the flexible elements to refine rather than as an excuse to wait.
- Reconcile the ISF against the commercial invoice and packing list. Seller, buyer, manufacturer, and HTSUS should agree across all three documents before transmission.
- Keep the power of attorney and ISF bond current. An expired bond can stop a filing cold at the worst moment.
- Withdraw cancelled bookings. A shipment that never sails still needs its ISF withdrawn, or it counts as a violation.
- Match ISF timing to your duty strategy. If goods will move into a warehouse before entry, coordinate the filing with your bonded warehouse and tariff-deferral plan so nothing conflicts downstream.
Compliance rules also differ sharply by destination, so a team importing into more than one market has to track more than the US regime. If your network also touches Latin America, the recent overhaul covered in our Mexico customs law reform guide is a reminder that "we file ISF" is not the same as "we are compliant everywhere."
Frequently asked questions
What is ISF 10+2?
ISF 10+2 is the Importer Security Filing, a mandatory electronic submission to US Customs and Border Protection for ocean cargo entering the United States. The importer supplies 10 data elements and the ocean carrier supplies 2, which is where the "10+2" name comes from. Its flexible enforcement period ended on January 26, 2010, and CBP tightened penalties further from July 9, 2013.
When must the ISF be filed?
The importer's data must reach CBP no later than 24 hours before the cargo is loaded onto the vessel at the foreign port. That is 24 hours before loading overseas, not before US arrival, so the filing is often complete weeks ahead of the ship docking in the United States.
What are the penalties for a late or inaccurate ISF?
According to CBP, liquidated damages run $5,000 per violation for a filing that is late, inaccurate, or incomplete, with exposure on a single shipment reaching up to $10,000. Importers can petition for mitigation, and claims are often cancelled on payment of $1,000 to $2,000 when no security goal was compromised.
Who files the ISF?
The legally responsible party is the ISF Importer, usually the importer of record, owner, buyer, or consignee. A licensed customs broker or forwarder typically transmits the filing under a power of attorney, but the importer keeps the legal liability even when someone else files.
What data is in the 10+2 filing?
The 10 importer elements are seller, buyer, importer of record number, consignee number, manufacturer, ship-to party, country of origin, HTSUS number, container stuffing location, and consolidator. The 2 carrier elements are the vessel stow plan and container status messages.
What is ISF-5, and how is it different?
ISF-5 is the shorter filing for cargo that transits the US rather than entering its commerce, such as freight remaining on board (FROB) and immediate-exportation moves. As the name implies, it requires only 5 data elements instead of the 10 an importer files for goods actually being imported. Most US importers deal with the standard ISF-10.
Does ISF apply to air or truck shipments?
No. The ISF 10+2 rule applies only to ocean cargo arriving in the United States. Air freight, and goods moving in by truck or rail across a land border, are not subject to the ISF, though they carry their own advance-data requirements.