How to Choose a Shelter Company in Mexico: Scorecard and RFP

To choose a shelter company in Mexico, send the same written RFP to every provider on your shortlist, score the answers on a weighted scorecard, verify the documents behind them, call current and former clients, and settle the exit terms before you sign. Price comes last, once compliance, labor and billing transparency have cleared.

The order matters because the shelter's compliance becomes part of your own tax position. Mexico has no official count of shelter providers, and the market runs from single-client operators to a handful of large multi-site firms, so quotes under the same label can describe very different businesses.

For how the shelter model works in the first place, start with the shelter companies in Mexico guide.

Why does the choice of provider carry so much weight?

A shelter holds an IMMEX program in the albergue modality, which the IMMEX Decree defines as one where foreign companies supply the technology and productive material "sin que estas últimas operen directamente el Programa," without operating the program themselves. The shelter imports under that program, employs the workforce and keeps the books.

Your income tax runs through it. Under Article 183-Bis of the income tax law, the shelter computes each foreign client's safe-harbor profit separately, and shelters are "responsables solidarios en el cálculo y entero del impuesto determinado por cuenta del residente en el extranjero," jointly liable for calculating and paying the tax determined on your account.

If the shelter breaches one of those obligations and does not cure it within 30 calendar days of a SAT requirement, it is suspended from the importers' register and "se considerará que el residente en el extranjero tiene establecimiento permanente en México." You would then carry the full Mexican tax obligations of a permanent establishment.

You also keep exposure the model does not move: you own the goods and machinery, you are typically the US importer of record, and your product-regulatory duties stay with you. This article is general information and does not constitute legal or tax advice.

The weighted shelter scorecard

Score each provider from 1 to 5 on every criterion, multiply by the weight, add the results and divide by 5 for a score out of 100. Adjust the weights to your case: a medical device maker might move points from billing to quality-system fit.

Criterion	Suggested weight	What strong looks like
Tax and customs compliance record	20	Program number disclosed, absent from suspension and cancellation notices, current positive SAT compliance opinion, safe-harbor calculation shown to you
Labor relations and payroll	15	Employer structure explained in writing, monthly proof of IMSS payments, severance funding agreed, a plan for the 2027 working week
Billing transparency	15	Sample invoice naming every pass-through, markup and exchange rate; adjustment index and cap in the contract
Certifications	10	IVA/IEPS certification current with renewals on record; OEA where inputs stay beyond 18 months
Site and time to production	10	Space in your target region, a lease covering the agreement term, a production date with stated assumptions
Sector and quality-system fit	10	Clients in your sector, a written quality agreement, training records you can inspect
Systems and data	5	Anexo 24 reports on request, your data exportable at exit
Contract, liability and governance	5	Named account lead, audit rights, liability for accidents, recalls and customs penalties allocated in writing
Exit and transition	10	Written commitments on employer substitution, asset transfer and certification support
Total	100

One rule sits above the arithmetic: a provider that scores 1 on compliance leaves the process, whatever its total. With named providers already on your shortlist, test the side-by-side provider comparisons against these criteria.

How do you compare shelter quotes?

Ask each provider for one all-in cost per employee per month, naming every transactional fee, markup and start-up charge and the roles you would hire yourself. Headline rates hide the differences: one shelter agreement filed with the SEC prices the fee per paid hour, tiered by peak headcount and floor area, while another bills wages and fringes as a pass-through and charges rent, utilities, customs broker fees, duties and freight outside the fee. The shelter program cost guide sets out the pricing models and how to put quotes on the same basis.

The shelter RFP: 36 questions to send every provider

Send every provider the same questions, in writing, with a deadline, and ask for the document wherever one exists.

IMMEX and customs

1. What is your IMMEX program number and modality, and which legal entity holds it?
2. Has the program appeared on a Ministry of Economy suspension or cancellation notice, and when did you file your last annual report?
3. How will my site be registered as an operating address, and how long did your last address addition take?
4. Which customs broker files your pedimentos, and how do you keep the transfer records, including proof of the productive process, that Customs Law Article 112 has required since January 1, 2026?
5. How do you track the 18-month limit on temporarily imported inputs, and do you hold OEA certification, which extends it to 36 months?

The annual report is due the last business day of May. In 2026 the ministry suspended 441 programs for a missing report and cancelled 189 from September 1. These Diario Oficial notices give you a public record to check; the annual-report suspensions guide explains the cycle.

HR, payroll and labor relations

6. Are you the direct employer of my workers, and how do you characterize that relationship under the 2021 subcontracting reform, including REPSE registration?
7. Will you give me monthly proof of IMSS contributions paid for those workers?
8. Which union, if any, holds the collective agreement at my site, and how fast will you notify me of a dispute or strike notice?
9. How do you calculate and bill profit sharing (PTU) for my workers?
10. How will your payroll handle the 46-hour maximum week and mandatory electronic time recording, both in force from January 1, 2027?
11. How is severance funded: a reserve built into invoices, a bond, or billing at termination?

No primary guidance found to date settles whether a shelter needs REPSE registration, so question 6 goes to your labor counsel. Social Security Law Article 15 A makes a party that contracts services with a provider in default on social-security obligations jointly liable for the workers used, hence question 7. PTU in a shelter is also unsettled, so get the method in writing.

Facilities and real estate

12. Who holds the lease on my building, and who signs it?
13. Does the lease, with renewals, cover the full term of the shelter agreement?
14. Which facility costs sit outside your fee: rent, utilities, maintenance, hazardous-waste disposal?
15. What first-production date do you commit to for this space, and what does it assume?

Compliance controls: Anexo 24, IVA/IEPS certification and SAT standing

16. Which Anexo 24 inventory control system do you run, and will you reconcile my inventory against pedimentos on request?
17. What IVA/IEPS certification tier do you hold, when does it expire, and has a renewal ever lapsed?
18. Will you provide a current positive SAT compliance opinion under Article 32-D of the Federal Tax Code and confirm the entity is absent from SAT's Article 69 and 69-B lists?
19. Who prepares my RFC registration, provisional and annual returns and DIEMSE, and will I receive the filed copies?
20. Will you show me the Article 183-Bis safe-harbor calculation for my operation each year, and how is the tax billed?

Under VAT Law Article 28-A, a certified IMMEX company credits 100 percent of the VAT due on temporary imports, and the certification runs one year, renewable within the 30 days before expiry; without it, only a bond avoids paying that VAT. In the shelter model providers describe, the provider holds the certification at its own tier, so a lapse in its renewal reaches your VAT position.

Reporting and billing transparency

21. Will you provide a sample invoice that names every pass-through, markup and transactional fee?
22. Which exchange rate converts peso costs to dollars, and does each invoice show it?
23. Which index drives the annual fee adjustment, is there a cap, and when do I see the calculation?
24. What deposits or pre-funding do you require, and on what terms are they returned?

Security

25. Which supply-chain security certifications do you hold in Mexico and the United States, and when does each expire?
26. How are my materials, finished goods and tooling segregated and access-controlled on site and in transit?

IT, systems and data

27. Who owns the data on my inventory, payroll and customs operations, and in what format do I receive it at exit?
28. Can my team read the inventory reports and pedimento files for my operation directly?
29. Which systems will my team use, and how are access rights, backups and security incidents handled?

Governance, insurance and liability

30. Who is my account lead, and what is the escalation path to your leadership?
31. How is liability allocated for workplace accidents, product recalls and customs penalties, and which insurance covers each?
32. What audit rights do I have over the books, records and site for my operation?
33. Which law governs the agreement, and where and in what language are disputes resolved?

Exit and transition

34. What is the initial term, what notice applies to renewal, and what does early termination cost in each year?
35. Will you commit in the contract to cooperate with an employer substitution under Federal Labor Law Article 41 and a virtual transfer of my machinery and inventory to my own IMMEX program?
36. Will you supply the records my new entity can use to count your personnel, infrastructure and investment toward its own IVA/IEPS certification under RGCE rule 7.1.8?

The SEC-filed agreements include a 36-month initial term with 12-month extensions exercised at least 90 days before expiry, an early-termination penalty in years one and two, 120 days' notice for the provider to terminate without cause, and a 60-month term in the second contract. Since 2021 an employer substitution takes effect only when the business assets pass to the new employer, so settle with Mexican labor counsel how that condition is met. The shelter vs own entity guide covers when to make the move.

The reference-check script

Ask each finalist for current clients and at least one former client, ideally one that moved to its own entity, and put the same questions to each:

1. How long have you operated with the provider, at what headcount, and in which city?
2. How did your first-production date compare with the proposal?
3. Has an invoice ever carried a charge you could not trace to the contract, and how was it resolved?
4. Has a SAT, IMSS or customs requirement reached your operation, and how did the provider handle it?
5. How did the provider handle a labor dispute or a large reduction in headcount?
6. Did you see the calculation behind each annual fee adjustment?
7. If you left, how did the transfer of workers, machinery and inventory go, and what would you negotiate differently?
8. Would you choose the same provider for your next site?

Red flags that end the conversation

• The provider will not disclose its IMMEX program number or the entity that holds it.
• Its program appears on a suspension or cancellation notice with no documented explanation. A cancellation for grounds such as missing goods, false documents or unproven transfers bars the company and its linked partners from export-promotion programs for five years.
• It cannot produce a current positive SAT compliance opinion, or its IVA/IEPS certification is near expiry with no renewal filed.
• It quotes a headline rate and declines to show a sample invoice or its exchange rate.
• It offers to buy your machinery or inventory, or suggests selling your output in Mexico without an export pedimento. Article 183 of the income tax law prohibits both for shelter clients.
• It claims a faster legal route to reclassify your goods. Any importer can request a SAT classification ruling, and SAT has up to three months to answer.
• It tells you all customs, labor and tax liability sits with the shelter. The safe-harbor tax is legally yours, and joint-liability rules can reach you.
• It will not put exit cooperation in writing.

How to choose a shelter company in Mexico, step by step

Each step ends at a decision gate, and a provider moves forward only when it clears it.

Step	What you do	Planning window	Decision gate
1. Requirements	Headcount ramp, regions, quality obligations, any Mexican sales, time horizon; set the weights	1 to 2 weeks	A signed-off brief
2. Shortlist	Screen for region, sector and scale	1 to 2 weeks	A shortlist that fits the brief
3. RFP	Send the 36 questions with a deadline	3 to 4 weeks	Complete answers with documents
4. Verify and score	Check Diario Oficial notices, compliance opinions and certifications	1 to 2 weeks	Compliance above the floor
5. Visits and references	Walk the space, run the reference script	2 to 3 weeks	Finalist confirmed
6. Negotiate	Counsel reviews liability, severance funding and exit clauses	3 to 6 weeks	Exit terms in the agreement
7. Onboard	Site registration, recruiting, first production	Provider estimates: typically 2 to 4 months, as little as 30 days in move-in-ready space, 10 to 15 months in a dedicated or build-to-suit shelter	First production

The windows for steps 1 to 6 are planning assumptions; adjust them to your calendar. An independent customs and IMMEX review of the finalists' answers fits at step 4.

If your ownership structure, site or timeline is still open, the Mexico Entry Readiness Diagnostic takes eleven questions and about three minutes and gives you a scored read on ownership structure, site, regulatory routing, landed cost and timeline before you write the brief.

Common pitfalls

• Choosing on the headline rate. A low rate can move cost into pass-throughs, markups and roles you end up hiring yourself.
• Assuming the shelter carries your quality system. ISO 13485 keeps responsibility for outsourced processes with you, under written quality agreements, and the FDA's QMSR final rule reads training duties as covering contractors; see the medical device shelter guide.
• Pricing a multi-year contract on 2026 labor rules. The maximum working week falls from 48 hours in 2026 to 46 in 2027 and 40 in 2030 with no cut in pay, and employer IMSS pension contributions rise every January through 2030. Ask how each change reaches your invoice and fold it into your labor plan.
• Leaving the exit for later. Providers estimate 12 to 18 months for a transition to your own entity, and its clauses are easiest to win before you sign.

The bottom line

Choosing a shelter provider is a compliance decision first and a pricing decision second. The provider files your safe-harbor tax, holds the program your goods move under and employs your workforce, so its record becomes part of yours.

Send the same 36 questions to every provider, score the answers with weights that fit your operation, check the documents against the public record, and write the exit into the agreement before you sign.

Calder & Vale is independent and sells no shelter services, so you get an unconflicted read on which model fits, help running the provider selection, and the entity and incentives work if you later build your own. If that would help, a complimentary 30-minute call is a good place to start, with no pitch and a reply within 24 hours.