How to qualify an IMMEX supplier in Mexico: a checklist for US buyers

A Mexican supplier will often lead with “we have IMMEX,” and many US buyers treat that as the qualification finished. It is not — it is one line on a longer checklist. The evidence behind the answers helps procurement, quality and trade teams decide what still needs assessment.

This page is that checklist: questions for requesting evidence, recording gaps and deciding what follow-up your US order needs.

Editorial note. This information is general and is not legal, tax, accounting, customs or procurement advice, nor a supplier recommendation. Verify any specific situation with official sources and qualified advisors. This site is an independent editorial resource operated by Heberey LLC; it does not represent the SAT, the Secretaría de Economía, VUCEM, Mexican Customs, or any chamber or authority.

Start with the right frame

Use the questions below to request documents, identify gaps and assign follow-up. A desk review cannot predict delivery or establish legal standing, product quality or capacity for your order. Those decisions need the responsible buyer, quality and trade teams and any further assessment they require.

Keep requested, provided, missing and needs review separate. Record the source and date of each answer; a vague answer is a question to resolve, not a supplier verdict. The introductory wording and generic FAQs on this page are not a substitute for that assessment.

One thing this page is not: it is written for the buyer vetting a supplier, not for a company seeking a program of its own. If you are the one applying, start with how to get an IMMEX program — eligibility, the export commitment and the file the Secretaría de Economía asks for.

1. Program and compliance status

IMMEX and the IVA/IEPS certification are different authorizations from different authorities. If an answer blurs them together, request separate evidence and clarification before drawing a conclusion.

2. Customer-supplied materials

If you will consign components, raw materials or tooling, ask:

• Can the supplier receive customer-supplied materials under its program?
• How are those materials segregated and tracked from the supplier’s own inventory?
• How are they reconciled back to what you sent?

If the answer is incomplete, record the missing material-tracking evidence and ask the responsible parties to resolve it before you commit customer-owned inputs.

3. Inventory control and reconciliation

The financial and customs benefits of IMMEX rest on inventory control. Ask:

• How do you control inventory, and can it reconcile with the Anexo 24 system?
• Can every entry and exit be tied to a pedimento?
• How do you handle shrinkage, scrap and discrepancies?
• What are your temporary-import deadlines, and how do you track them?

Request a dated example showing the relevant inventory-to-document relationship, and ask how unexplained differences are assigned and closed. Missing evidence does not establish that a disruption will occur.

Trace one finished lot back to the material supplier

Pick a component that matters to the US importer and ask the Mexican plant to walk one finished lot backwards. Start with the packing list for the outbound lot, then find the work order, the material issue and the receiving record. For a purchased input, identify the upstream producer and the records connecting that producer to the lot. Record the document reference and custodian at each step.

Suppose two coil lots went into one production run. If the supplier can identify the distributor but only one mill lot, enter the second lot as an open item in the evidence register. Assign a follow-up owner and due date before the buyer releases the order. Use redacted samples for qualification and exchange any detailed production records through the parties’ agreed secure channel.

Where forced-labor risk is relevant, the US importer can use this exercise to locate gaps for specialist review. A Mexican finishing operation or a supplier declaration alone cannot establish the origin of all upstream inputs. CBP forced labor guidance

4. Quality systems

Ask your quality team which contractual or sector requirements apply to this product and site. Applicability is unconfirmed until your quality team confirms it; the following are topics to discuss, not universal entry requirements:

• whether ISO 9001 is relevant to your requirements;
• whether IATF 16949 is relevant to the automotive scope under discussion;
• sector-specific standards (medical, aerospace, food, etc.) where relevant.

If a certificate is provided, record issuer, scope, site, dates and the status of any issuer check. Ask for relevant process evidence and nonconformity follow-up. A copy alone does not establish current validity or performance on your order.

Check the certificate number, covered legal entity, site address, processes and expiry date with the issuer or the relevant scheme directory. For a quoted weekly volume, ask production planning for an anonymized recent run on the proposed machine or line, including shift hours, accepted output, scrap and time already committed. Compare the spare capacity with your peak release. On a site visit, have the auditor observe that operation, locate the gauges and follow a selected lot through inspection. Record separately what the desk reviewer received and what the auditor actually observed.

5. Logistics and border lanes

Qualification is incomplete without the border:

• Which crossings do you use (Laredo, El Paso, Tijuana)?
• Who are your customs brokers and carriers?
• How do you handle cross-docking and drayage (see Mexico cross-border logistics)?
• What are realistic lead times to my destination?

Those lanes affect the lead-time and logistics assumptions for your order.

6. Capacity, financial stability and references

• Can they handle your volume and its variability?
• Is there evidence of financial stability to sustain the relationship?
• Can they provide references from comparable US customers?

The evidence register

Use one row per request, with request date, received date, document date/version, source, status and follow-up owner. Use not yet confirmed when a date, scope or source has not been established. These are evidence fields, not a supplier score.

On a narrow screen, scroll the table sideways to see every column.

Mark a request provided only when an item was actually received; that is a receipt status. Use missing when no item was supplied and needs review when scope, consistency or currency is unresolved. Separate document statements, any dated source checks and your remaining questions. Do not convert missing evidence into a legal finding or a supplier recommendation.

To request bids using a common scope, prepare a cross-border RFQ in the existing worksheet using the same scope and assumptions.

Don’t skip the visit

For meaningful volume, a plant visit or a credible third-party audit is hard to replace. Documents set a baseline; seeing the operation reveals the gaps. For higher-value or higher-risk sourcing decisions, a site visit or qualified third-party audit can add evidence that documents alone cannot provide.

Connect this task to the US entry

• Prepare a shipment-level UFLPA evidence trail

Recommended official sources

To verify program and trade details, consult directly:

• SNICE / Secretaría de Economía, for IMMEX program information;
• the SAT, for the customs regime and the IVA/IEPS certification;
• the USMCA / T-MEC official text, for rules of origin;
• and qualified advisors or customs brokers familiar with the specific operation.