IOR Number: Importer of Record Number Explained for CBP Entries

Key Points

• The IOR number identifies the party liable for duties, which 19 CFR 149.3(a)(3) says is the importer of record, liable for payment of all duties.
• The importer establishes the IOR number on CBP Form 5106, Create/Update Importer Identity Form, before its first formal entry, under 19 CFR 24.5.
• The CATAIR Entry Summary Create/Update (September 2025) carries the IOR number in the 11-record in one of three formats: IRS EIN NN-NNNNNNNXX, SSN NNN-NN-NNNN, or CBP-assigned YYDDPP-NNNNN.
• CBP keys the bond, statement batching, ACE portal visibility, Center assignment and liquidation notices to the IOR number, so a wrong suffix or stale Form 5106 address misroutes bills, refunds and notices.
• The IOR number is not a bond number, filer code, ultimate consignee number or DUNS number.

On this page

1. At a glance
2. What is an IOR number and where does it come from?
3. Who is responsible for the IOR number and when is it used?
4. How is the IOR number reported in ACE and on the 7501?
5. Common IOR number errors and what they cost
6. How the IOR number differs from other entry identifiers
7. Frequently asked questions
8. What importers and brokers should do
9. Key references

An IOR number is the importer of record number: the IRS Employer Identification Number (EIN), optionally suffixed, the Social Security Number (SSN), or the CBP-assigned number that identifies the party liable for duties on a CBP entry. Importers establish it on CBP Form 5106 before their first formal entry, and customs brokers report it on every entry summary in ACE and on CBP Form 7501. It is not a bond number or a filer code.

At a glance

• Full name: Importer of record number (IOR number)
• Who prepares or uses it: The importer establishes it; the customs broker reports it; CBP keys bonds, statements and notices to it
• When in the lifecycle: Set up before the first formal entry, then reported on every entry summary through liquidation
• System or channel: CBP Form 5106 (revised form in ACE as of March 16, 2019); ACE entry summary 11-record; CBP Form 7501 (02/26)
• Formats: IRS EIN NN-NNNNNNNXX; SSN NNN-NN-NNNN; CBP-assigned YYDDPP-NNNNN
• Governing authority: 19 CFR 24.5; 19 CFR 149.3(a)(3); CATAIR Entry Summary Create/Update (September 2025)
• Related terms: CBP-assigned number, ultimate consignee number, entry number format, entry type 01, 03 and 06

The links in this article go to the primary documents: the regulations, CBP forms and the ACE CATAIR pages themselves. Read the source. This entry reflects those documents as of November 2026.

What is an IOR number and where does it come from?

The IOR number is the identifier CBP uses to tie every formal entry to the one party legally liable for the duties on it. Under 19 CFR 149.3(a)(3), the importer of record is liable for payment of all duties, and the IOR number is how that liability is recorded on the entry. For background on who may act as importer of record, see Importer of Record: Owner, Purchaser, Broker, or Non-Resident.

The three IOR number formats

The CATAIR Entry Summary Create/Update chapter (September 2025) recognizes three formats. A business with an IRS EIN reports it as NN-NNNNNNNXX, where XX is an optional suffix that lets one EIN support distinct importer identities. An individual may use an SSN in the format NNN-NN-NNNN. A party with neither, usually a foreign company, receives a CBP-assigned number, the importer identification number CBP issues through CBP Form 5106, in the format YYDDPP-NNNNN.

CBP Form 5106 as the source record

Every IOR number starts as a CBP Form 5106, Create/Update Importer Identity Form, record filed under 19 CFR 24.5. CBP moved the revised form into ACE on March 16, 2019. The 5106 holds the names and addresses CBP uses for mailing and billing, which is why keeping it current matters as much as getting the number right.

Who is responsible for the IOR number and when is it used?

The importer owns the IOR number and must establish it on CBP Form 5106 before its first formal entry; the broker then reports it on each entry. The importer controls the 5106 data, including addresses and any suffix, and is responsible for updating it when the business moves, reorganizes or changes its billing contacts. Confirm with your broker or CBP whether a given update can be filed by the broker on your behalf.

Once established, the IOR number travels with the entry from summary filing to liquidation. CBP keys the continuous or single transaction bond, periodic statement batching, ACE portal visibility, Center of Excellence and Expertise assignment and liquidation notices to the IOR number. Any refunds or bills generated after liquidation follow the address on file for that number.

How is the IOR number reported in ACE and on the 7501?

The IOR number is transmitted by the broker in the ACE entry summary 11-record defined in the CATAIR Entry Summary Create/Update (September 2025), and it is printed on CBP Form 7501 (02/26). The ACE record is the authoritative data; the 7501 reflects the same value. Check the current CATAIR for field position and validation rules before programming or changing ABI software.

The IOR number is reported the same way regardless of entry type. An entry type 01 (Consumption, Free and Dutiable, the ordinary formal consumption entry), an entry type 03 (Consumption, AD/CVD, for goods under an antidumping or countervailing duty order) and an entry type 06 (Foreign Trade Zone, the consumption entry withdrawing zone merchandise into U.S. commerce) all carry the importer of record number. On type 03 entries the IOR number matters especially, because AD/CVD deposits and later liquidation bills attach to that party.

Common IOR number errors and what they cost

The most common IOR number error is a wrong or missing suffix on an EIN, which places the entry under a different importer identity than intended. The entry may then draw on the wrong bond, land in the wrong statement batch, or be invisible to the right ACE portal account.

• Wrong suffix: Statements, bills and refunds post to the wrong identity, and reconciling them takes manual work with CBP.
• Stale Form 5106 address: Liquidation notices, bills and refund checks go to an old address, which can mean missed deadlines and delayed money.
• Confusing identifiers: Entering the ultimate consignee number, a filer code, a bond number or a DUNS number in place of the IOR number puts liability on the wrong record or fails validation.
• Using an EIN before the 5106 exists: An IOR number not yet established on CBP Form 5106 will not support a formal entry.

Brokers who want to see which entries post under a given IOR number can pull ACE reports; see the ES-003 Guide for one example.

How the IOR number differs from other entry identifiers

The IOR number identifies the liable party, while most other entry data elements identify a filing, a location or a carrier. Keeping them distinct prevents the most expensive data errors.

• Ultimate consignee number: the EIN, SSN or CBP-assigned number of the ultimate consignee, the party on whose account goods are shipped. It is reported with the IOR number and can be the same party, but it does not carry duty liability.
• Entry number format: the 11-character CBP entry number of three-character filer code, seven-digit sequence and one check digit identifies the filing, not the importer. See Entry Number Format.
• FIRMS code: the Facilities Information and Resources Management System code, a four-character identifier of the bonded facility holding the cargo.
• SCAC code: the Standard Carrier Alpha Code, the two-to-four-letter identifier issued by the National Motor Freight Traffic Association for the importing carrier.
• Schedule D port codes: the Census Schedule D four-digit district and port codes, such as port code 5301 for the Houston, TX seaport in customs district 53 Houston-Galveston.

Frequently asked questions

Can a foreign company have an IOR number?

Yes. A foreign party without an IRS EIN or SSN obtains a CBP-assigned number through CBP Form 5106, and that CBP-assigned number serves as its IOR number in the format YYDDPP-NNNNN.

Is the IOR number the same as the bond number?

No. The IOR number identifies the importer; CBP keys the bond to the IOR number, but the bond has its own identifier. Never report a bond number in the IOR number field.

What does the suffix on an EIN-based IOR number do?

The suffix, shown as XX in the CATAIR format NN-NNNNNNNXX, distinguishes separate importer identities under one EIN. Each suffixed IOR number has its own CBP Form 5106 record, so confirm which suffix applies before filing.

How do I change the address tied to my IOR number?

File an update on CBP Form 5106 in ACE. Confirm with CBP or your broker how long the change takes to reach billing and liquidation notices.

What importers and brokers should do

The IOR number is only as reliable as the CBP Form 5106 record behind it, so treat that record as live data.

• Verify the IOR number, including any suffix, against the importer's 5106 record before the first entry and after any corporate change.
• Review 5106 addresses at least whenever a mailing, billing or refund address changes.
• Configure ABI templates so the IOR number and ultimate consignee number fields cannot be swapped or filled with a filer code, bond number or DUNS number.

Key references

The primary documents governing the IOR number are listed below.

• 19 CFR 24.5: regulation behind importer identification and CBP Form 5106.
• 19 CFR 149.3: paragraph (a)(3) makes the importer of record liable for payment of all duties.
• CBP forms: CBP Form 5106 Create/Update Importer Identity Form and CBP Form 7501 (02/26).
• ACE CATAIR: Entry Summary Create/Update (September 2025), including the 11-record and IOR number formats.