ISF Filing Explained: 10+2 Elements, Deadlines, and Who Files
Key Points
- ISF (the "10+2" filing) is a security data requirement for ocean cargo destined for the United States, governed by 19 CFR Part 149; it is not a customs entry and carries no duty.
- The ISF-10 must be transmitted no later than 24 hours before cargo is laden aboard the vessel at the foreign port of loading.
- The importer of record, or an agent filing on the importer's behalf, is responsible; a continuous bond covers the filing, or a single-transaction ISF bond can be used instead.
- Two of the ten importer elements, the container stuffing location and consolidator, may be submitted as late as 24 hours before the vessel's arrival at the first U.S. port.
- Air, truck, and rail shipments are entirely exempt from the ISF requirement.
On this page
- What ISF is and what it is not
- The 10 importer data elements
- The 2 carrier elements
- ISF-5 for in-transit cargo
- Deadlines and flexible timing rules
- Who files, what bond is required, and what it costs
- Updating your filing and what happens when things go wrong
- What importers should do
- Key references
The Importer Security Filing is a pre-shipment security transmission required by U.S. Customs and Border Protection (CBP) for ocean cargo bound for the United States. The importer, or an authorized agent, must electronically submit specific data elements before cargo is loaded onto the vessel overseas. The requirement does not create a customs entry, does not trigger duty payment, and does not replace the commercial entry filed upon arrival.
The links in this article go to the primary documents: the regulations, Federal Register notices, and official CBP guidance themselves. Read the source.
What ISF is and what it is not
CBP created the ISF program under the authority of the Security and Accountability for Every Port Act (the SAFE Port Act) to give CBP advance risk-targeting data on ocean containers before they are loaded abroad. The full regulatory framework lives at 19 CFR Part 149.
ISF is strictly a security filing. It does not replace the Entry Summary (CBP Form 7501), the Arrival Notice, or any other post-arrival commercial document. No duties are collected or assessed on the ISF itself. First-time importers sometimes confuse the ISF with entry; the two filings have different deadlines, different data sets, and different legal consequences for errors. If you are working through pre-shipment obligations for the first time, the First Time Importer Requirements: The Pre-Shipment Checklist covers the broader sequence of steps.
Only ocean cargo is in scope. Air freight, truck crossings, and rail shipments are expressly exempt.
The 10 importer data elements
The standard ISF for most ocean imports is called the ISF-10 because the importer must provide ten data elements. Under 19 CFR Part 149, those ten elements are:
- Seller - the name and address of the last known entity that sold the goods.
- Buyer - the name and address of the last known entity that purchased the goods.
- Importer of record number - the IRS EIN, SSN, or CBP-assigned number of the party responsible for the customs entry.
- Consignee number - the IRS EIN, SSN, or CBP-assigned number of the party to whom the goods are consigned at the time of entry.
- Manufacturer or supplier - the name and address of the entity that manufactured, produced, or supplied the goods.
- Ship-to party - the name and address of the first deliver-to party in the United States after the goods clear customs.
- Country of origin - the country in which the goods were manufactured or produced.
- Six-digit HTS number - the Harmonized Tariff Schedule commodity code at the six-digit level. The full HTS is published at hts.usitc.gov.
- Container stuffing location - the name and address of the physical location where the goods were stuffed into the container.
- Consolidator - the name and address of the party who stuffed the container or arranged for its stuffing.
Flexible elements
Not all ten elements share the same hard deadline. The container stuffing location and consolidator are recognized as information that may not be available 24 hours before lading. CBP requires those two elements to be provided as early as possible and no later than 24 hours before the vessel arrives at the first U.S. port of unlading. In practice this means you file a placeholder ISF with the other eight elements before lading, then amend it with the stuffing location and consolidator data in transit.
Similarly, the manufacturer or supplier, ship-to party, country of origin, and six-digit HTS number may all be updated after the initial filing, up until 24 hours before the vessel arrives at the first U.S. port. If better information becomes available, you are expected to update the filing to reflect it.
The 2 carrier elements
The "plus 2" elements are the responsibility of the ocean carrier, not the importer, and they are governed by 19 CFR 4.7c and 4.7d:
- Vessel stow plan - a map of where every container is positioned on the vessel, transmitted to CBP after the vessel departs the last foreign port.
- Container status messages (CSMs) - event-based messages tracking container movements throughout the voyage.
Importers and brokers are not responsible for submitting the carrier elements, but understanding them is useful when troubleshooting discrepancies in CBP's Automated Targeting System.
ISF-5 for in-transit cargo
A reduced five-element ISF, called the ISF-5, applies to cargo that will not be entered for consumption in the United States but that will transit U.S. ports. The three categories and their timing rules differ:
- Foreign cargo remaining on board (FROB) - cargo that arrives and departs on the same vessel without offloading. The ISF-5 for FROB is due any time before the cargo is laden at the foreign port.
- Immediate exportation (IE) in-bond - cargo offloaded and immediately exported. The ISF-5 is due no later than 24 hours before lading at the foreign port.
- Transportation and exportation (T&E) in-bond - cargo transported through the U.S. interior and then exported. The ISF-5 is also due no later than 24 hours before lading at the foreign port.
Deadlines and flexible timing rules
The core ISF-10 rule is straightforward: the filing must reach CBP no later than 24 hours before the cargo is laden aboard the vessel at the foreign port. This is often called the "24-hour rule," though that phrase also refers to a separate advance manifest rule for carriers; in the ISF context it means 24 hours before lading, not 24 hours before U.S. arrival.
Summary of timing rules
- Elements 1-8 (seller through HTS): no later than 24 hours before lading at the foreign port.
- Elements 9-10 (stuffing location and consolidator): no later than 24 hours before arrival at the first U.S. port.
- Updates to manufacturer, ship-to party, country of origin, and HTS: permitted until 24 hours before U.S. arrival.
- ISF-5 for FROB: any time before lading.
- ISF-5 for IE and T&E in-bond: no later than 24 hours before lading.
The duty to update is ongoing. If information in a filed ISF changes before the cargo arrives, the filer must amend the filing to reflect the accurate data. Filing accurate initial data and then neglecting amendments is itself a violation.
Who files, what bond is required, and what it costs
Who is responsible
The legal obligation to file the ISF-10 rests with the importer of record. In practice, most importers delegate the filing to their licensed customs broker or freight forwarder. The delegation does not transfer legal liability: if the filing is late, incomplete, or inaccurate, CBP looks to the importer of record.
Filing is done electronically through CBP's Automated Broker Interface (ABI) or the Automated Manifest System (AMS). No paper form exists. Most brokers and forwarders have direct ABI connections and file ISFs as a routine part of their pre-clearance services.
Bond requirement
Every ISF must be secured by a CBP bond. If the importer already holds a continuous import bond, that bond extends to ISF filings and no additional bond instrument is needed. Importers who do not maintain a continuous bond must obtain a single-transaction ISF bond for each shipment. The continuous bond is almost always the more economical choice for importers who ship regularly.
Service fees
Customs brokers and freight forwarders typically charge a flat fee per ISF filing. Rates vary by provider and volume; you should request a fee schedule from your broker before your first shipment. No government fee is assessed by CBP for the ISF transmission itself.
Updating your filing and what happens when things go wrong
CBP's ISF enforcement focuses on three failure modes: late filings, inaccurate data, and failure to update. Each can result in a do-not-load order, a hold on the cargo after arrival, or a monetary penalty under 19 CFR Part 149. Penalties and the specific dollar exposure they create are a detailed topic in their own right and are covered in a dedicated article on ISF penalties. Similarly, the interaction between ISF timing and other entry deadlines is addressed in our article on entry process deadlines.
The practical message: treat the 24-hour-before-lading window as a hard cutoff, build your supply-chain communications so that seller, buyer, HTS, country of origin, and manufacturer data reach your broker before that window closes, and establish a process for routing stuffing-location updates from your consolidator or freight forwarder to your broker while the vessel is at sea.
What importers should do
- Confirm with your customs broker or forwarder that they have a direct ABI connection and that ISF filing is included in your service agreement before the first shipment sails.
- Verify that a continuous bond covering ISF is in place; if not, arrange a single-transaction ISF bond for each shipment well in advance of the 24-hour-before-lading deadline.
- Build an internal checklist, or use your existing pre-shipment checklist, that captures all ten data elements from your suppliers early enough to meet the lading deadline, and designate a responsible person to push stuffing-location and consolidator data to your broker while the vessel is in transit.
- Treat every change to manufacturer, ship-to party, country of origin, or HTS number as a trigger to amend the ISF immediately, and confirm with your broker that the amendment was accepted in ABI before the vessel arrives.
Key references
- 19 CFR Part 149 - the complete Importer Security Filing regulation, including all ten importer elements, timing rules, and amendment obligations.
- 19 CFR Part 4 (sections 4.7c and 4.7d) - carrier obligations for the vessel stow plan and container status messages.
- CBP Importer Security Filing (10+2) overview page - CBP's official program summary, FAQ, and links to CSMS guidance messages.
- Harmonized Tariff Schedule of the United States (hts.usitc.gov) - authoritative source for the six-digit HTS classifications required in element 8.
- Federal Register, Vol. 73, No. 228 (Nov. 25, 2008) - the ISF final rule establishing the 10+2 program.
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