ISF Filing: The Complete 10+2 Guide for US Importers

What Is ISF Filing — and Who Must File?

The Importer Security Filing (ISF) is a data report required by US Customs and Border Protection. It must be filed before cargo is loaded onto a vessel bound for the United States. The trade calls it 10+2: the importer supplies 10 data elements and the carrier supplies 2 more. CBP uses the data to screen containers for security risks before they ever leave the origin port.

ISF applies to ocean freight only. Air, truck, and rail shipments do not need it, because they fall under different advance data rules. If your goods arrive at a US seaport on a vessel, an ISF is required. That holds whether the cargo is a full container, an LCL shipment, or breakbulk.

The legal duty sits with the ISF importer. For standard imports, that is the importer of record or the owner of the goods. You can hire an agent, such as a licensed customs broker, to transmit the filing. The penalty exposure stays with you either way.

ISF is separate from the customs entry that clears your goods after arrival. Think of it as the security pre-screen, while the entry is the fiscal and legal clearance. We cover that second stage in our customs clearance process guide.

The 10 Importer Data Elements (Plus the Carrier's 2)

Here are the 10 data elements the importer side must transmit. Most come straight from your supplier and your commercial invoice.

• Seller — Name and address of the last party who sold the goods, usually your supplier on the commercial invoice.
• Buyer — Name and address of the last party who bought the goods, usually your company.
• Importer of record number — Your IRS number, EIN, social security number, or CBP-assigned number.
• Consignee number — The IRS or CBP number of the party in the US receiving the goods. Often the same as the importer of record.
• Manufacturer or supplier — Name and address of the party who made or supplied the finished goods.
• Ship-to party — Name and address of the first place the goods will be delivered in the US, such as your warehouse or 3PL.
• Country of origin — Where the goods were made, matching what you will declare on the customs entry.
• HTS classification — The tariff code for each product, to at least the 6-digit level. It must line up with the entry filing later.
• Container stuffing location — Name and address of the place where the container was packed.
• Consolidator (stuffer) — Name and address of the party who stuffed the container or arranged the stuffing.

Flexible Elements and the Carrier's Side

Two of the 10 elements get extra time. The container stuffing location and the consolidator may be filed as late as 24 hours before the vessel arrives in the US. The other 8 are due 24 hours before loading at origin. In practice, file all 10 together — split filings invite errors.

Four elements also allow a flexible range at first: manufacturer, ship-to party, country of origin, and HTS code. You may file your best knowledge and update later. You must amend the ISF as soon as better data exists, and no later than 24 hours before US arrival.

The +2 belongs to the carrier, not to you. Ocean carriers transmit the vessel stow plan and container status messages directly to CBP. You never handle those two elements, but they explain the 10+2 name.

The Deadline: 24 Hours Before Vessel Loading

The ISF must be accepted by CBP no later than 24 hours before the cargo is laden aboard the vessel at the foreign port. The clock runs from loading at origin, not from departure and not from US arrival. This catches many first-time importers off guard.

Work backwards from the port cut-off. Origin terminals usually close for cargo 2-4 days before the vessel sails. That means your real-world ISF window sits around 72 hours, or more, before the departure date on your booking. On a busy lane like China to USA, treat the supplier packing list as the trigger: once the container is stuffed, file.

Transshipment does not reset the clock. The deadline applies to loading at the first port where the cargo starts its journey to the US on the delivering vessel chain. When in doubt, file against the earliest possible loading date.

If data changes after filing, amend. CBP expects updates until the goods arrive. An amended ISF filed in good time is routine; an absent or late one is a violation.

How to File an ISF Step-by-Step

The filing itself takes minutes once the data is in hand. Gathering the data is the real work. Follow these six steps for every ocean shipment.

1. Gather the data from your supplier: Request all 10 elements at booking time, not after the container is packed. A one-page ISF template sent with your purchase order keeps suppliers consistent.
2. Appoint a filer: Most importers use a licensed customs broker or their forwarder's brokerage partner. Self-filing is possible but requires your own software link to CBP.
3. Transmit the filing via ABI or AMS: The filer sends the 10 elements electronically to CBP, tied to the lowest bill of lading number on the shipment. Aim for 48-72 hours before loading.
4. Verify acceptance: Confirm that CBP accepted the filing and that the bill of lading number matches the carrier's manifest exactly. A mismatch leaves the ISF unmatched and flags the shipment.
5. Amend if anything changes: New ship-to address, corrected HTS code, different stuffing location — update the ISF as soon as you know, and before the vessel reaches the US.
6. Keep your records: CBP recordkeeping rules generally require import records to be kept for five years. Save the ISF transaction number with the shipment file.

ISF Penalties: What CBP May Assess

CBP may assess liquidated damages of up to $5,000 per violation. Late filing, inaccurate data, an incomplete filing, and failure to amend or withdraw each count as separate violations. Penalties on a single ISF are generally capped at $10,000.

First offenses often end in a warning or a mitigated amount under CBP's published guidelines. Do not build your process around that hope. Repeat violations draw full penalties and put your company on CBP's radar for future cargo.

The indirect costs usually hurt more than the fine. A missing or late ISF can trigger a hold or an intensive exam at the US port. Exam fees, container moves, and storage commonly add $500-$2,500 per container, plus one to two weeks of delay. In serious cases, CBP can issue a Do Not Load order at origin, and your cargo never boards the vessel.

There is no insurance against ISF penalties. The only protection is a process that files early, checks data against documents, and amends fast when something changes.

The Bond Requirement: ISF Bond vs Continuous Bond

Every ISF must be secured by a bond. The bond is CBP's financial guarantee that any liquidated damages will be paid. Without it, the filing cannot be accepted.

Most regular importers use a continuous customs bond. It covers all ISF filings and all customs entries for a full year, across every US port. As of mid-2026, a $50,000 continuous bond typically costs around $250-$550 per year through a surety. If you import more than three or four ocean shipments a year, it is almost always the cheaper option.

One-off importers can use a single transaction entry bond plus a separate ISF bond, sometimes called an ISF-D appendix bond. The combined cost per shipment is often $100-$200. Your broker or your forwarder's brokerage partner arranges either type through a surety company.

ISF-5: Transit Cargo and FROB

Not all cargo on a US-bound vessel is destined for the US. Freight remaining on board (FROB) passes through a US port on its way elsewhere. Immediate exportation (IE) and transportation and exportation (T&E) shipments move through the US in bond. These movements need an ISF-5 instead of the full ISF-10.

The ISF-5 has five elements: booking party, foreign port of unlading, place of delivery, ship-to party, and the HTS code. For FROB cargo, the carrier or the party causing the goods to arrive usually files. If you route cargo through a US port to reach Canada, Mexico, or the Caribbean, confirm who files the ISF-5 before the vessel loads. Most importers reading this guide will only ever need the standard ISF-10.

Common ISF Mistakes to Avoid

The same handful of errors causes most ISF penalties and holds. Check your process against this list, and keep our customs documents checklist next to every booking.

• Filing late. Waiting for perfect data is the top mistake. File your best knowledge 48-72 hours before loading and amend later if needed.
• Mismatched HTS codes. The ISF code and the customs entry code should align. A mismatch between the two filings is a classic exam trigger.
• Wrong consignee or importer number. A typo in an EIN leaves the ISF unmatched in CBP's system, which reads the shipment as having no filing at all.
• Missing manufacturer details. Trading companies often hide factory names. You still must report the actual manufacturer or supplier, not just the middleman.
• Not amending after changes. A changed ship-to warehouse or corrected origin must be updated before arrival. An outdated ISF counts as inaccurate.
• Assuming someone else filed. Suppliers and carriers do not file your ISF-10. Confirm the transaction number for every shipment before the container is loaded.

ISF vs Customs Entry: How the Two Filings Connect

ISF and the customs entry are separate filings with separate deadlines and separate penalties. They describe the same shipment, so CBP cross-checks them. Clean importers keep one data source feeding both.

When the ISF says one manufacturer and the entry says another, or the HTS codes diverge, the shipment profile looks inconsistent. Inconsistency drives exams, and exams drive cost and delay. The fix is simple: build both filings from the same commercial invoice and packing list.

How Suaid Global Helps

Suaid Global is an asset-light freight forwarder. We are not a licensed customs broker; ISF filings and customs entries are handled by the licensed brokerage partners in our network. What we bring is the coordination that keeps the 24-hour deadline from ever becoming your problem.

When you book ocean freight with us, ISF data collection starts at the purchase order. We chase your supplier for the 10 elements and check them against the invoice and packing list. A clean file reaches the brokerage partner well before the loading cut-off. You receive the ISF transaction number as confirmation, every shipment.

If your data changes mid-transit, we manage the amendment with the same partner who filed. And because the same data feeds the customs clearance at destination, your ISF and entry stay consistent — which is the quiet secret to fewer exams. Send us your next booking and we will map the ISF timeline for you.