Importer Security Filing (ISF 10+2) is a mandatory U.S. Customs and Border Protection (CBP) security requirement for ocean cargo entering the United States. Before goods are loaded onto a vessel bound for the U.S., importers and ocean carriers must electronically submit shipment information to CBP for security screening and risk assessment.
ISF was introduced to strengthen supply chain security by allowing CBP to identify high-risk shipments before they depart from foreign ports. While customs brokers often file ISF on behalf of importers, the legal responsibility for filing accurate and timely information ultimately rests with the importer.
This guide explains everything you need to know about ISF 10+2, including filing requirements, deadlines, required data elements, exemptions, penalties, and best practices for maintaining compliance.
ISF 10+2 Is a Mandatory Security Filing for Ocean Imports
Importer Security Filing (ISF), commonly referred to as ISF 10+2, is a pre-arrival security filing required by U.S. Customs and Border Protection (CBP) for cargo imported into the United States by ocean vessel.
The filing provides CBP with advance information about imported goods before they are loaded overseas, allowing the agency to assess security risks and target potentially dangerous shipments before they reach U.S. ports.
ISF applies only to ocean freight. It does not apply to shipments arriving by air, truck, or rail.
Importer Security Filing (ISF)
An electronic filing submitted to CBP before cargo is loaded onto an ocean vessel destined for the United States. Importers provide ten data elements while ocean carriers provide two additional data elements.
U.S. Customs and Border Protection (CBP)
The federal agency responsible for securing U.S. borders, facilitating lawful international trade, collecting customs duties, and enforcing import regulations.
Ocean Carrier
A shipping company that transports containers by sea. Ocean carriers are responsible for submitting two carrier-specific data elements as part of the ISF 10+2 requirement.
Importer of Record (IOR)
The individual or business legally responsible for ensuring imported goods comply with U.S. customs laws, including ISF compliance, customs entry, duty payment, and recordkeeping.
What Does “10+2” Mean?
The name 10+2 refers to the total number of data elements required before an ocean shipment arrives in the United States.
- 10 data elements are provided by the importer (or its authorized customs broker).
- 2 data elements are submitted separately by the ocean carrier.
Together, these filings provide CBP with the information needed to perform advance cargo risk assessments before containers are loaded onto vessels.
Although the importer and carrier submit different information, both filings work together to support supply chain security and facilitate legitimate trade.
Why ISF Was Introduced
Following the events of September 11, 2001, the United States implemented several initiatives to strengthen cargo security and identify potential threats before shipments reached U.S. ports.
Importer Security Filing became one of the key programs designed to enhance visibility into international supply chains by requiring shipment information before cargo is loaded overseas.
Today, ISF helps CBP:
- Identify high-risk shipments
- Improve cargo screening
- Prevent smuggling and terrorism
- Enhance supply chain security
- Facilitate faster clearance for compliant importers
- Improve targeting of cargo examinations
Rather than delaying inspections until goods arrive in the United States, CBP can evaluate shipment data well before vessels begin their voyage.
Who Must File ISF?
ISF generally applies to the Importer of Record (IOR) or the party responsible for bringing commercial goods into the United States.
Although importers often authorize licensed customs brokers to submit ISF electronically, legal responsibility remains with the importer.
Parties commonly involved include:
- Importers
- Importers of Record (IOR)
- Licensed Customs Brokers
- Authorized Agents
- Freight Forwarders acting under authorization
- Non-Vessel Operating Common Carriers (NVOCCs) for certain ISF-5 filings
Working with a customs broker simplifies the filing process, but importers should verify that all submitted information is accurate and complete.
Which Shipments Require ISF?
ISF is required for most commercial cargo transported to the United States by ocean vessel.
Typical shipments requiring ISF include:
- Full Container Load (FCL)
- Less than Container Load (LCL)
- Commercial imports
- Retail inventory
- Manufacturing components
- Amazon FBA ocean shipments
- Consolidated ocean freight
Whether goods are shipped in a single container or consolidated with other importers’ cargo, ISF generally applies when transportation is by ocean.
Which Shipments Are Exempt?
Not every shipment entering the United States requires an Importer Security Filing.
Common exemptions include:
- Air freight shipments
- Truck shipments from Canada or Mexico
- Rail shipments
- International mail
- Certain military cargo
- Certain government shipments
- Passenger baggage
Although these shipments are exempt from ISF, they remain subject to other applicable CBP reporting and customs requirements.
The importer portion of ISF consists of ten required data elements that describe the shipment, the parties involved, and the imported merchandise.
Accurate information is essential because errors or omissions may result in shipment delays, cargo examinations, or monetary penalties.
The required importer data elements are:
- Manufacturer (or Supplier)
- Seller
- Buyer
- Ship To Party
- Container Stuffing Location
- Consolidator (Stuffer)
- Importer of Record Number
- Consignee Number
- Country of Origin
- Harmonized Tariff Schedule (HTSUS) Number
Each of these elements helps CBP understand where goods originate, who is responsible for them, and how they should be classified under U.S. customs regulations.
The 10 Importer Data Elements Explained
1. Manufacturer (or Supplier)
This identifies the company that manufactured, produced, assembled, or supplied the imported goods.
Providing the correct manufacturer information helps CBP trace products back to their source and assess potential security risks.
2. Seller
The seller is the last known entity that sold the goods before they were exported to the United States.
This information helps establish the commercial transaction behind the shipment.
3. Buyer
The buyer is the individual or business purchasing the goods for import into the United States.
In many cases, the buyer is also the Importer of Record.
4. Ship To Party
This identifies the first physical delivery location within the United States where the imported goods are intended to arrive after customs clearance.
The ship-to location may differ from the buyer’s business address.
5. Container Stuffing Location
This refers to the physical location where cargo was loaded into the shipping container.
Knowing where containers were packed helps CBP perform more accurate cargo risk assessments.
6. Consolidator (Stuffer)
The consolidator is the company responsible for loading multiple shipments into a container or arranging the cargo for export.
For Less than Container Load (LCL) shipments, this is often a freight consolidator.
7. Importer of Record Number
This is typically the importer’s IRS Employer Identification Number (EIN), Social Security Number (SSN), or CBP-assigned importer number.
It identifies the party legally responsible for the import transaction.
8. Consignee Number
The consignee is the party receiving the imported goods in the United States.
In many cases, this information matches the Importer of Record, although it may differ depending on the transaction.
9. Country of Origin
The country of origin identifies where the goods were manufactured or substantially transformed.
This information affects duty rates, admissibility requirements, trade agreements, and regulatory compliance.
10. Harmonized Tariff Schedule (HTSUS) Number
The HTSUS classification identifies the imported product under the Harmonized Tariff Schedule of the United States.
Correct classification is critical because it determines applicable duties, trade measures, and regulatory requirements.
The 2 Carrier Data Elements
Unlike the importer’s ten data elements, the final two elements are submitted directly by the ocean carrier.
These include:
Vessel Stow Plan
A detailed electronic map showing where every container is positioned aboard the vessel.
This information helps CBP identify container locations during inspections and evaluate cargo security risks.
Container Status Messages (CSMs)
Electronic messages generated throughout the shipping process that track significant container movements and events, such as loading, unloading, gate movements, and transfers.
CSMs provide CBP with greater visibility into the movement of containers before they arrive in the United States.
Although carriers are responsible for submitting these two elements, importers should understand how they fit into the overall ISF 10+2 program and why timely communication with shipping partners is essential.
When Must ISF Be Filed?
Timing is one of the most important aspects of Importer Security Filing compliance.
For most ocean shipments, the importer’s ISF must be submitted at least 24 hours before the cargo is loaded onto the vessel at the foreign port of departure. This is commonly known as the 24-hour rule.
Waiting until the vessel has departed is too late. Late or missing filings may result in shipment delays, cargo examinations, and financial penalties.
Whenever possible, importers should submit ISF as soon as sufficient shipment information becomes available rather than waiting until the last minute.
Understanding the 24-Hour Rule
The 24-hour rule requires ISF information to reach U.S. Customs and Border Protection (CBP) before cargo is loaded onto an ocean vessel destined for the United States.
For example:
- If a vessel is scheduled to depart Shanghai on Friday at 6:00 PM, the ISF should generally be accepted by CBP no later than Thursday at 6:00 PM.
- If shipment details change after filing, the ISF should be updated as soon as accurate information becomes available.
Submitting early provides time to correct validation errors and reduces the risk of compliance issues.
Why Early Filing Is Recommended
Many importers mistakenly wait until the shipment is ready to depart before gathering ISF information.
Instead, importers should begin collecting the required data as soon as a purchase order is confirmed.
Early filing provides several advantages:
- More time to verify supplier information
- Fewer filing errors
- Reduced risk of CBP holds
- Better coordination with customs brokers and freight forwarders
- Improved supply chain visibility
For regular importers, incorporating ISF into the purchasing process rather than the shipping process can significantly improve compliance.
Who Can File an ISF?
Although the importer is legally responsible for ISF compliance, the filing itself may be submitted by an authorized party.
Common filing parties include:
- Importer of Record
- Licensed Customs Broker
- Authorized Agent
- Freight Forwarder acting under authorization
Regardless of who files the ISF, the importer remains responsible for ensuring the information submitted to CBP is complete and accurate.
Filing Through a Licensed Customs Broker
Most importers authorize a licensed customs broker to prepare and submit the ISF electronically through CBP’s Automated Broker Interface (ABI).
This simplifies the filing process because brokers already have access to CBP systems and understand import documentation requirements.
However, brokers rely entirely on the information provided by suppliers, freight forwarders, and importers. Incorrect information supplied to the broker may still expose the importer to penalties.
Power of Attorney (POA)
Before a customs broker can file an ISF on your behalf, they generally require a valid Power of Attorney (POA).
A POA authorizes the broker to act as your representative when communicating with CBP and submitting customs documentation.
Without a valid authorization, the broker cannot legally file your ISF.
ISF Bond Requirements
Many first-time importers are surprised to learn that ISF filings are generally supported by a customs bond.
A customs bond guarantees payment of duties, taxes, fees, and certain compliance obligations owed to CBP.
Depending on your importing activity, you may use either:
- Single Entry Bond (SEB)
- Continuous Bond
The right option depends on how frequently you import goods into the United States.
Single Entry Bond (SEB)
A Single Entry Bond covers one specific shipment.
It is often suitable for businesses importing occasionally or making one-time purchases.
Each shipment requires its own bond.
Continuous Bond
A Continuous Bond remains active for twelve months and covers unlimited imports during that period.
Businesses importing regularly often choose a Continuous Bond because it is generally more cost-effective and simplifies customs compliance.
Many frequent importers also use a Continuous Bond to avoid arranging a separate bond for every shipment.
ISF vs. Customs Entry
Although they are closely related, ISF and Customs Entry serve different purposes.
| Feature | ISF 10+2 | Customs Entry |
| Purpose | Security screening | Customs clearance |
| Filed Before | Cargo loading overseas | Cargo arrival in the U.S. |
| Submitted To | CBP | CBP |
| Applies To | Ocean imports only | Most commercial imports |
| Main Focus | Supply chain security | Duty assessment and cargo release |
An ISF filing does not replace a Customs Entry.
Importers typically need both to legally import commercial goods into the United States.
What Is ISF-5?
Not every ocean shipment requires the standard ISF 10 filing.
Certain shipments moving through the United States without entering U.S. commerce use a simplified filing known as ISF-5.
Examples include:
- Freight Remaining on Board (FROB)
- Immediate Exportation (IE)
- Transportation and Exportation (T&E)
- Goods moving in-bond through the United States
Because these shipments are not intended for U.S. consumption, fewer data elements are required.
Can an ISF Be Amended?
Yes, in many situations, shipment information changes after the initial ISF has been submitted.
Common updates include:
- Manufacturer information
- HTSUS classification
- Country of origin
- Container stuffing location
- Consolidator details
Importers should update the filing as soon as corrected information becomes available.
Keeping ISF information current demonstrates good-faith compliance and helps reduce potential enforcement issues.
ISF Penalties
Failure to comply with ISF requirements can result in significant consequences.
Potential violations include:
- Late filing
- Failure to file
- Inaccurate filing
- Missing required data
- Failure to update amended information
CBP may assess liquidated damages of up to $5,000 per violation.
In addition to monetary penalties, importers may experience:
- Cargo holds
- Intensive examinations
- Delayed cargo release
- Increased inspection rates
- Supply chain disruptions
Maintaining accurate records and filing on time remains the best way to avoid enforcement actions.
Common ISF Filing Mistakes
Many ISF penalties result from preventable errors rather than intentional violations.
Common mistakes include:
- Incorrect HTSUS classification
- Filing after the 24-hour deadline
- Incorrect manufacturer information
- Missing container stuffing location
- Incorrect consignee details
- Waiting for final commercial documents before filing
- Failing to amend updated shipment information
Establishing a standardized document collection process with overseas suppliers can significantly reduce these errors.
Best Practices for ISF Compliance
Successful importers treat ISF as an integral part of their supply chain rather than a last-minute customs requirement.
Recommended best practices include:
- Collect shipment information before booking ocean freight.
- Work closely with suppliers to obtain complete data.
- File as early as possible.
- Verify HTSUS classifications before submission.
- Review all information before authorizing filing.
- Maintain clear communication with customs brokers.
- Monitor shipment updates and amend filings when necessary.
- Keep import records organized for future audits.
A proactive compliance process helps reduce delays, avoid penalties, and improve supply chain efficiency.
Frequently Asked Questions
What is ISF 10+2?
ISF 10+2 is a U.S. Customs and Border Protection security filing required for most commercial ocean shipments entering the United States. Importers submit ten data elements, while ocean carriers submit two additional data elements before cargo is loaded overseas.
Who files the ISF?
The importer is legally responsible for the filing, although licensed customs brokers or authorized agents commonly submit it on the importer’s behalf.
When is ISF due?
For most shipments, ISF must be filed at least 24 hours before cargo is loaded onto the vessel at the foreign port.
Is ISF required for air freight?
No. ISF applies only to ocean cargo. Air, truck, and rail shipments follow different CBP reporting requirements.
What is an ISF bond?
An ISF bond is generally provided through a customs bond, such as a Single Entry Bond or Continuous Bond, which guarantees compliance with CBP requirements.
What is ISF-5?
ISF-5 is a simplified filing used for certain in-bond shipments, including Freight Remaining on Board (FROB), Immediate Exportation (IE), and Transportation and Exportation (T&E).
Can I amend an ISF after filing?
Yes. If shipment information changes after submission, importers should update the filing as soon as accurate information becomes available.
What happens if ISF is filed late?
Late filings may result in cargo delays, customs examinations, and liquidated damages of up to $5,000 per violation.
Does ISF replace Customs Entry?
No. ISF is a security filing submitted before loading, while Customs Entry is used to clear imported goods and assess duties after arrival.
Does my customs broker handle everything?
Customs brokers often prepare and submit ISF filings, but the importer remains legally responsible for the accuracy and timeliness of the information provided.
