Adding a New Address or Second Plant to Your IMMEX Program

A second plant, a warehouse or a new site under your existing IMMEX program is an alta de domicilio inside the same program. It is not a new program. The change runs through three registries in order: the RFC with SAT, the program with the Secretaría de Economía, and, if you hold the IVA and IEPS certification, AGACE.

The sequence matters because the goods follow the addresses. Temporarily imported goods may only sit at addresses registered in your program. Goods found anywhere else are a cause for suspension and cancellation, and the Ley Aduanera reform in force since 1 January 2026 raised the evidence standard around them.

If you are still choosing where the second plant goes, the best states to manufacture in Mexico and the state manufacturing incentives guide come first.

Do you need a new IMMEX program for a second plant?

No. Rule 3.2.24 of Economía's foreign trade rules, titled "Altas y bajas de domicilio," requires IMMEX holders to "actualizar permanentemente el registro a través de altas y/o bajas" of the plants, warehouses and storage sites where they hold temporarily imported goods or operate.

The IMMEX Decree sets the two rules underneath. Article 24, section VI, requires you to keep temporarily imported goods "en el o los domicilios registrados en el Programa." Article 24, section VII, requires you to request the change of registered addresses from Economía, "previo trámite ante el SAT," and "por lo menos con tres días hábiles de anticipación" to moving goods to the new address.

What is the sequence for adding an address?

Step	Registry	What you file	Timing
1. Premises	Your landlord	A lease, sublease or loan agreement with a forced term of at least one year	At least 11 months left when you file with Economía
2. RFC	SAT	Notice of opening an establishment, ficha 29/CFF	Within the month after opening, before other SAT filings
3. Program	Economía, through the Ventanilla Digital	Alta de domicilio under rule 3.2.24	At least three business days before goods move
4. Certification	AGACE	Notice on ficha 62/LA, if you hold the IVA and IEPS certification	Within five days
5. Inventory	Your own systems	The new address set up in your Anexo 24 inventory control	Before the first shipment

The RFC comes first. Article 11 of the Decree requires your fiscal address and every address where you operate under the program to be "inscritos y activos en el Registro Federal de Contribuyentes," and Economía checks it every year. The Reglamento del Código Fiscal, Article 29, sets the notice of opening an establishment "dentro del mes siguiente," and before any other filing with SAT.

Then Economía. The trámite in the Ventanilla Digital is "Modificación Alta a domicilio de una planta, bodega o almacén." Rule 3.2.24 asks for:

• A written statement under oath describing the production process at the new address stage by stage, with the machinery, equipment, personnel and duration of each stage.
• Proof of legal possession of the property, with a forced term of at least one year and "por lo menos once meses" left at filing.
• Proof of legal possession of the machinery and equipment, where there is any.

Economía resolves with an official letter. Rule 3.2.37 gives it ten business days for program changes, counted from a complete file, and the Decree states that silence after that term "se entenderá que la Secretaría resolvió favorablemente." Rule 1.3.9, amended on 12 February 2026, lets Economía inspect an address before authorizing it or at any time while the program runs, and a visit has to take place within ten business days of the request. Plan the filing so the resolution is in hand before the first shipment.

Then the certification, if you hold it. For IVA and IEPS holders, rule 7.2.1 of the RGCE 2026 requires a notice when the document proving legal use of your premises changes "referente a la vigencia, las partes y el domicilio," and ficha 62/LA sets the deadline at five days. The rule does not say "new plant" in so many words, and the conservative reading treats a new plant's lease as such a change. The lease address has to "coincidir plenamente" with an address registered with SAT. OEA holders also file a notice within the month after the RFC notice, with an updated company profile for each facility.

Our IMMEX IVA certification guide covers the rest of that registration.

Which lease terms apply to the new site?

Two tests apply, and the stricter one governs.

Registry	Forced term	Time left at filing
Economía, alta de domicilio (rule 3.2.24)	At least one year	At least 11 months
SAT, IVA and IEPS certification (rule 7.1.1)	At least one year	At least 8 months

A short lease or a renewal near expiry can block the alta. Rule 3.2.24 also allows a company with an industrial-modality program to register a warehouse operated by a third party with a storage services contract, provided it covers the same address, meets the same term and identifies the storage area.

Rule 3.2.5 allows two IMMEX companies, or an IMMEX company and a company without a program, to share one address, provided each has legal possession and the facilities are "delimitadas físicamente entre sí y sean independientes."

Is a notary's fe de hechos required?

Not for adding an address under the current rules. Rule 3.1.1 requires a fe de hechos for a new program, a pre-operative period, a services expansion and a new PROSEC program. Rule 3.2.24 is not on that list. Some English guidance still ranking for this question describes a notary statement because it predates Economía's 2022 rules.

How do goods move between sites?

The answer depends on whose site receives them.

Between your own registered sites. The rules control the move through registration and records. The receiving address is registered before goods arrive, goods in transit carry a CFDI with the Carta Porte complement under the reformed Article 146 of the Ley Aduanera, and the Anexo 24 inventory system follows the goods. A company in the border region moving goods to its own registered plants in the interior files form B10 under RGCE rule 4.3.6.

To another IMMEX company. Rule 4.3.21 sets the virtual transfer: a temporary import pedimento in the receiver's name on the day of the transfer, and a return pedimento in your name by the next day. The receiver pays IVA unless it holds the certification or a guarantee, and has six months to return the goods or import them definitively.

Two 2026 changes apply to these transfers. Article 112 of the Ley Aduanera now requires everyone involved to keep the documentation that proves "el proceso productivo al que se sometió la mercancía transferida." The Reglamento de la Ley Aduanera, reformed on 23 February 2026, adds in Article 166 that the goods have to be "acorde al proceso productivo de la empresa que la recibe."

Is submanufacture an alternative to a second plant?

Often, when the goal is capacity rather than a site of your own. Article 21 of the Decree lets you send temporarily imported goods to a third party for submanufacture, and rule 3.2.31 states that submanufacture also covers complementing "la capacidad de producción o de servicios cuantitativa" of the program holder.

	Your own second plant	Submanufacturer
Registration	Alta de domicilio, rule 3.2.24	Registro de submanufactureras, rule 3.2.31
Premises	Your lease, 11 months left at filing	The submanufacturer's, same term test
What you describe	Your process by stage, with machinery and staff	The process by stage, with tariff classification
Ongoing filing	Inventory and the program's annual report	A monthly notice on ficha 71/LA within the first five days of the next month
Liability	Yours	The submanufacturer is jointly liable
Standing check	Your own RFC and certification	The submanufacturer's positive tax compliance opinion

The submanufacturer's address has to be registered and active in the RFC as well, and since 23 February 2026 the transfer notice also goes into the electronic file that proves the operation.

What happens when you close or move a plant?

You file a baja de domicilio with Economía by written notice stating the reasons, and the notice of closing the establishment with SAT within the month after. Before that, the inventory at the closing site goes to an address already registered in the program, filed at least three business days ahead.

Getting this wrong is costly. Temporarily imported goods not found at the registered addresses are a cause for cancelling the program under Article 27 of the Decree, for suspension from the importer registry under RGCE rule 1.3.3, and for cancelling the IVA and IEPS certification under rule 7.2.4.

A change of fiscal address follows its own clock: a notice to SAT within ten days under Article 27 of the tax code, and a written notice to Economía within ten business days under rule 3.2.39.

The IMMEX program itself is the foundation under all of these registrations. In 2026 Economía cancelled 189 programs from 1 September, citing both the missing annual report and Article 11, section III, of the Decree, the requirement that every operating address be registered and active in the RFC. Our note on the 2026 IMMEX suspensions covers the deadline.

What changes when the second plant is in another state?

A new state adds three registrations that sit outside the IMMEX program.

State payroll tax. The impuesto sobre nóminas is levied by each state where you have an establishment. Querétaro's law, for example, applies it when your "locales, establecimientos, agencias o sucursales" are in the state. The rate is 3 percent in Nuevo León and Guanajuato under their current laws, and 3 percent in Querétaro according to the state finance secretariat. Nuevo León's congress rejected a proposal to raise it to 4 percent for 2026. Check the rate and any exemption for new investment in the state you choose.

IMSS. The IMSS affiliation regulation, Article 13, assigns a company "un número de registro patronal por cada municipio" where it has a workplace, unless it requests a single registration in writing. Workers are registered within five business days under Article 15 of the Ley del Seguro Social.

Municipal land use. Article 115 of the Constitution gives municipalities the power to authorize land use, so the new site needs its land-use licence from the municipality where it sits. Monterrey, for example, runs it through its urban development secretariat.

The hiring guide covers the payroll burden, and site selection and incentives covers how the state you choose shapes the package around the plant.

The bottom line

A second plant under IMMEX is an alta de domicilio in the program you already hold. The order is RFC first, then Economía at least three business days before goods move, then the five-day certification notice if you are certified, with the inventory system ready before the first shipment.

The lease decides more than it seems: eleven months left at filing for Economía, and an address that matches SAT's records exactly. In a new state, add the payroll tax registration, the IMSS registration for the municipality and the land-use licence.

The customs, trade and IMMEX practice coordinates the filings with a licensed customs broker. If you want a second read on your own expansion, a complimentary 30-minute call is available, and you will hear back within 24 hours.