English-speaking accountant in Mexico City: tax guide for expats and foreign companies (2026)

When do foreigners and foreign companies need a Mexican accountant?

You need a Mexican accountant the moment you generate income that Mexico can tax: when you become a tax resident (article 9 of the Federal Fiscal Code, CFF), when your foreign company creates a permanent establishment in Mexico (article 2 of the Income Tax Law, LISR), or when you receive Mexican-source income even without residing here (article 1, fraction III of the LISR). In all three cases you must register with the tax authority (SAT), obtain an RFC and file returns. An English-speaking accountant turns this from a translation problem into a solved problem.

In practice, the trigger is rarely the visa: it is the activity. Renting out an apartment in Mexico City, invoicing a Mexican client, opening a local entity, hiring staff or spending enough time here to shift your center of vital interests are all events that create obligations. Getting the analysis right early is cheaper than untangling penalties later.

How do I get an RFC as a foreigner in Mexico?

The RFC (Registro Federal de Contribuyentes) is Mexico's taxpayer ID, and registration is mandatory for anyone who must pay taxes or file returns under article 27 of the CFF. As a foreigner you obtain it by booking an appointment at a SAT office (or through a consulate in some cases), presenting your immigration document (residency card or, in defined cases, passport), proof of a Mexican address and a valid email. Foreign companies register through their legal representative and supporting corporate documents, typically apostilled and translated.

Two practical notes. First, the RFC is the gateway to almost everything else: issuing or receiving valid invoices (CFDI), opening certain bank products and complying with withholding rules. Second, the SAT process is in Spanish and document-sensitive, which is exactly where an English-speaking accountant saves you repeat trips. If you are setting up a company rather than registering as an individual, our calculadora de constitución de empresa gives you a quick sense of the setup costs involved.

Am I a tax resident in Mexico? (article 9 CFF)

You are a Mexican tax resident if you have established your home (casa habitación) in Mexico. If you also have a home abroad, residency is decided by your center of vital interests, which the law defines in article 9, fraction I of the CFF: you are resident here when more than 50% of your total annual income comes from Mexican sources, or when the main center of your professional activities is located in Mexico. This is the single most important test for any expat, because residency determines whether Mexico taxes your worldwide income or only your Mexican-source income.

The distinction is decisive. A Mexican tax resident is taxed on worldwide income (article 1, fraction I of the LISR). A non-resident is taxed only on Mexican-source income (article 1, fraction III of the LISR), usually via withholding. Getting the classification wrong in either direction creates risk: over-declaring abroad, or under-declaring in Mexico and facing a credit (crédito fiscal) from the SAT later.

What is a permanent establishment for a foreign company?

A permanent establishment (establecimiento permanente) is any fixed place of business through which a foreign company carries out, wholly or partly, its business activities in Mexico, as defined in article 2 of the LISR: branches, offices, factories, workshops, mines or any place of extraction of natural resources. A dependent agent who habitually concludes contracts in the name of the foreign company can also create one. Once a permanent establishment exists, the foreign company is taxed in Mexico on the income attributable to it (article 2 and articles 153 onward of the LISR).

This is where foreign companies most often misjudge their exposure. Selling into Mexico from abroad is generally not a permanent establishment; having a person here who signs deals, a fixed office, or local infrastructure can be. Because the line is fact-specific and the tax cost of crossing it is real, it deserves a deliberate analysis with a Mexican accountant before you scale local operations.

Which tax regime applies to me as an individual? (RESICO and others)

As a resident individual you are taxed under Title IV of the LISR. The most common regimes for professionals and small operators are RESICO for individuals (Régimen Simplificado de Confianza, articles 113-E to 113-J of the LISR), the general professional and business activity regime, and the leasing regime for rental income (Chapter III of Title IV). RESICO offers reduced ISR rates on a progressive scale tied to income, with an annual income cap to qualify (the cap is set at $3,500,000 MXN, a 2025 value, to be confirmed for 2026).

Choosing the right regime is not cosmetic: it changes your effective rate, your bookkeeping load and your withholding obligations. An expat earning professional fees, a foreigner renting out property, and a foreign founder drawing income from a Mexican startup may each land in a different regime. If your income comes from a company you are building here, see contador para startups; if you are deciding what a local accountant should cost, the calculadora de honorarios de contador gives you a market range.

IVA and ISR: what do I actually pay? (situation to obligation table)

Two taxes drive most situations: ISR (income tax, LISR) and IVA (value-added tax, LIVA). The general IVA rate is 16% (article 1 of the LIVA), with a 0% rate for certain activities and exemptions for others (articles 2-A and 9 of the LIVA). ISR depends on your residency and regime. The table below maps common expat and foreign-company situations to the Mexican obligation they typically trigger. Treat it as a map, not a ruling: your facts decide the outcome.

Will I be taxed twice? (double-taxation treaties and the foreign tax credit)

Usually not, if it is handled correctly. Mexico has an extensive network of double-taxation treaties (with the United States, Canada, the United Kingdom, Spain, Germany and many others) that allocate taxing rights between countries and prevent the same income from being taxed twice. On top of the treaties, Mexican domestic law gives residents a foreign tax credit: article 5 of the LISR lets you credit income tax paid abroad against your Mexican ISR on that same foreign-source income, within the limits the article sets.

The credit is not automatic. It requires documentation of the foreign tax paid, correct sourcing of the income and respect for the article 5 LISR limit, which caps the credit at the Mexican tax that would have applied to that income. Treaties also reduce withholding rates on dividends, interest and royalties when you certify residency. Getting this paperwork right is precisely the work that protects expats and foreign companies from paying tax twice, and it is hard to do blind across two tax systems and two languages.

Why use an English-speaking accountant instead of doing it yourself?

Because the cost of a mistake is asymmetric. The SAT operates in Spanish, its deadlines are unforgiving, and a misclassified residency, a missed RFC obligation or an unclaimed treaty benefit can turn into a crédito fiscal with surcharges and updates (arts. 17-A and 21 CFF). An accountant who works in your language removes the translation layer between you and a system that does not bend for foreigners.

Praxium gives you that clarity without the jargon: a first session at no cost to map your residency, regime and obligations, and a clear plan in English. If your situation also involves an SAT notice or audit, that is defensible too; start with defensa fiscal SAT or run a free diagnóstico fiscal to see where you stand before anything escalates.