MID Code: Manufacturer Identification Code Explained for Brokers

Key Points

• The MID code identifies the manufacturer or shipper of each entry line and is required on every line of an entry summary and on the cargo release.
• For textiles and apparel, 19 CFR 102.23 requires the MID code to be constructed from the name and address of the entity performing the origin-conferring operations under 19 CFR 102.21.
• CBP uses the MID code for targeting, AD/CVD company identification, textile production verification and MID-based holds, so a wrong MID is a common CBP Form 28 subject and audit finding.
• The most frequent errors are taking the MID from the invoice header when the factory differs by line, reusing one MID across factories, and abbreviations that change between filings.
• A MID code is not a DUNS number, not a supplier account number, not the foreign exporter ID and not an AD/CVD case suffix.

On this page

1. At a glance
2. What is a MID code and where does it come from?
3. Who is responsible for the MID code and when is it transmitted?
4. How does CBP use the MID code?
5. Common MID code errors and what they cost
6. How the MID code interacts with other ACE functions
7. Frequently asked questions
8. What importers and brokers should do
9. Key references

The MID code (Manufacturer Identification code) is the code on an ACE entry and the CBP Form 7501 that identifies the manufacturer or shipper of each entry line, derived from the entity's country code, name and address. Customs brokers build and transmit it for importers on both the cargo release and the entry summary, and CBP relies on it from release through post-entry review. For textiles and apparel, it must identify the entity that performed the origin-conferring operations.

This entry reflects requirements as of November 2026. The links in this article go to the primary documents: the regulations, CBP form instructions and official CBP pages themselves. Read the source.

At a glance

• Full name: Manufacturer Identification code (MID)
• Who prepares or uses it: The customs broker or self-filing importer prepares it; CBP uses it for targeting and review
• When in the lifecycle: At cargo release and on every entry summary line
• System or channel: ACE via ABI; manufacturer ID field described in the CBP Form 7501 (02/26) instructions
• Governing authority: CBP Form 7501 (02/26) instructions; 19 CFR 102.23 for textiles and apparel; CBP TBT-05-031
• Related terms: MID construction, ACE Cargo Release, ACE AD/CVD case management, CATAIR Appendix B

What is a MID code and where does it come from?

A MID code is a derived identifier, not a registry number: no agency issues it, and the filer builds it from the manufacturer's own name and address each time the line is prepared. The method is covered in our entry on MID construction (CBP's rule for building a Manufacturer Identification code from the manufacturer's country code, name, street address and city; a derived code, not an assigned registry number). This article covers what the MID code is for and how it is used, not the step-by-step build.

The general requirement to report a manufacturer ID appears in the CBP Form 7501 (02/26) instructions. For textile and apparel goods, 19 CFR 102.23 goes further: the MID must be constructed from the name and address of the entity performing the origin-conferring operations determined under 19 CFR 102.21. CBP also addressed MID reporting in CBP TBT-05-031; confirm the current text of that guidance on cbp.gov before relying on it.

What a MID code is not

The MID code is not a DUNS number, not a supplier or vendor account number from the importer's ERP, not the foreign exporter ID, and not the company suffix on an AD/CVD case number. Each of those fields serves a different purpose and has its own place in the transaction.

Who is responsible for the MID code and when is it transmitted?

The customs broker, or the importer if it self-files, is responsible for building the MID code from the commercial invoice or the importer's product master for each line and transmitting it. The importer remains responsible for giving the broker accurate manufacturer names and addresses, especially where a trading company or seller appears on the invoice instead of the factory.

The MID code travels twice. It is sent on the ACE Cargo Release (the ACE transaction, successor to the paper CBP Form 3461 and the ACS Simplified Entry, through which the broker transmits the data CBP needs to decide release), and again on each line of the entry summary. Both must identify the same manufacturer for the same goods. See ACE Cargo Release: How Brokers Transmit Release Data to CBP.

How does CBP use the MID code?

CBP uses the MID code to connect each entry line to a specific foreign producer, which supports four functions named in this brief.

• Targeting: risk analysis keyed to manufacturer history.
• AD/CVD company identification: matching the producer to the company-specific rates published through ACE AD/CVD case management (the ACE function, with its public ADCVD Search, through which CBP publishes Commerce's case numbers, company suffixes, cash deposit rates, effective dates and liquidation instructions). See ACE AD/CVD Case Management.
• Textile production verification: checking whether the named factory actually performed the origin-conferring work.
• MID-based holds: holding cargo associated with particular manufacturers.

Because holds can key off the MID code, it affects whether the broker receives disposition codes (ACE cargo release disposition codes, the status messages CBP returns describing what happened to a release) showing a hold or a 1C release (disposition code 1C, meaning CBP has released the entry). Background is in Disposition Codes: How ACE Cargo Release Status Messages Work.

Common MID code errors and what they cost

A wrong MID code, most often naming the seller instead of the factory, a trading company or a forwarder, is a common subject of a CBP Form 28 request for information and a recurring audit finding.

Typical mistakes

• Header MID on every line: taking the MID from the invoice header when the manufacturer differs by line.
• One MID for many factories: reusing a single MID across separate production sites.
• Drifting abbreviations: spelling or abbreviating the manufacturer's name differently between filings, so the same factory appears as several MIDs.
• Wrong entity for textiles: naming a party other than the one performing the origin-conferring operations required by 19 CFR 102.23.

Consequences include information requests, delayed release, flawed AD/CVD identification and adverse audit findings. Penalty exposure depends on the facts; confirm specifics with CBP.

How the MID code interacts with other ACE functions

The MID code sits in the importer's entry data, so several adjacent ACE functions affect where and when it is reported.

• ACE truck eManifest (ACE e-Manifest: Trucks, the electronic manifest highway carriers transmit before arrival at a land border port) carries carrier and shipment data, but the MID code comes from the broker's release and entry, not the manifest.
• ACE in-bond (the electronic in-bond system for moving unentered merchandise under bond) moves goods before entry; the MID is reported when the goods are entered. See ACE in-bond.
• ACE reconciliation (ACE Reconciliation, entry type 09, for later reconciliation of undeterminable value, classification, 9802 or FTA issues) does not relieve the filer of reporting an accurate MID code on the underlying entry summary; confirm scope with CBP.
• CATAIR Appendix B (CATAIR Appendix B, Valid Codes, the ABI code tables) and the record layouts in the ACE CATAIR govern field formats; confirm the MID field position there.
• Your ABI client rep (ABI client representative, the CBP Office of Trade contact for each ABI filer) can help with MID-related rejects. See ABI client rep.

Frequently asked questions

Is a MID code required on every entry line?

Yes. The MID code is required on every entry line, and the manufacturer can differ line by line on the same invoice.

Can I use the seller or trading company as the MID code?

Generally the MID code should identify the manufacturer, not a seller, trading company or forwarder; for textiles it must be the entity performing the origin-conferring operations under 19 CFR 102.23.

Is a MID code the same as a DUNS number?

No. A MID code is derived from the manufacturer's country, name and address, while a DUNS number is a separate commercial identifier and is not a substitute.

Does the MID code affect AD/CVD entries?

Yes. CBP uses the MID code for AD/CVD company identification, so it should match the producer reflected in the case data keyed on the line; the case suffix itself is a separate field.

What importers and brokers should do

• Keep a controlled manufacturer master with one fixed MID code per factory and consistent name spelling.
• Capture manufacturer name and address at the line level, not just the invoice header.
• For textiles, document which entity performs the origin-conferring operations under 19 CFR 102.21 and 102.23.
• Check that the MID on the cargo release and entry summary match before transmission.

Key references

• 19 CFR 102.23: textile and apparel MID built from the entity performing origin-conferring operations.
• 19 CFR 102.21: textile and apparel rules of origin referenced by 102.23.
• CBP forms page: CBP Form 7501 (02/26) instructions, including manufacturer ID.
• CBP trade page: search for CBP TBT-05-031 and current MID guidance.
• ACE CATAIR: ABI record layouts and code tables.