The essentials
- The RFC (Registro Federal de Contribuyentes) is your Mexican tax ID, issued by SAT.
- Registration is free and in person at a SAT office, with an appointment booked online or in the SAT app.
- Bring your original immigration document, proof of address no more than four months old and a valid official ID.
More things to know
- SAT expects you to register within the month after you start an economic activity in Mexico.
- Getting an RFC can come with tax obligations — talk to a Mexican accountant (contador) about what it means for you.
In this guide
Not every resident needs an RFC, but many eventually do — to invoice Mexican clients, work locally, sell a home with the residence exemption, or open some bank products. Registration itself is simple; understanding what it commits you to is the part worth getting advice on.
RFC vs CURP vs e.firma
| ID | Who issues it | What it's for | How you get it |
|---|---|---|---|
| CURP | Population registry | Personal ID number for government and banking | Comes with your residency card |
| RFC | SAT | Tax ID for income, invoices and property sales | Free SAT appointment (below) |
| e.firma | SAT | Digital signature for filing and signing tax procedures online | Separate SAT procedure once you have an RFC |
When you need one
- You'll earn income from Mexican sources or invoice Mexican clients
- You're employed by a Mexican company (your employer will need it)
- You're selling Mexican property and want to claim the primary-residence exemption
- A bank or other institution asks for it for a particular product
Documents SAT asks for
- Your valid immigration document — original
- Proof of address — original, no more than four months old
- A valid official ID
- If someone registers on your behalf: a notarized power of attorney and their ID
- If it applies: your foreign tax ID number
How registration works
- Book an appointment through the SAT portal, the SAT Móvil app or gob.mx.
- Attend your SAT office with the original documents. SAT says the service takes up to 40 minutes, with a maximum 5-minute wait if you have an appointment.
- Answer the advisor's questions about your activities.
- Leave with your registration receipt — the acuse único de inscripción — showing your RFC, a guide to your tax obligations and a QR code.
Get tax advice first
Keep reading
Taxes
Taxes for expats
How taxes work when you move to Mexico: when you become a Mexican tax resident under the Federal Tax Code, what Mexico taxes and at what rates, selling a home, property taxes, and what US citizens must keep filing.
Money
Banking & money
How expats handle money in Mexico: the cards to bring, opening a Mexican bank account, moving money from the US or Canada cheaply, SPEI and phone-number transfers, avoiding ATM and exchange fees, and paying bills.
Housing · Buying
Buying property
How foreigners legally buy property in Mexico: the restricted zone and the bank trust (fideicomiso), the notary's role, step-by-step closing, closing costs, due diligence and the red flags to walk away from.
Residency · Canje
Canje: visa to residency card
You have 30 days after entering Mexico to exchange your consulate visa for a residency card at INM. Here is the exact process, the documents, the 2026 fees and the mistakes that cost people their visa.
Frequently asked questions
How much does it cost to get an RFC in Mexico?
Nothing. SAT's registration for foreigners is free.
Can I get an RFC online as a foreigner?
SAT's procedure for foreign individuals is in person, at a SAT office with an appointment booked online or in the app.
What documents do foreigners need for an RFC?
Your original immigration document, original proof of address no more than four months old, and a valid official ID — plus a power of attorney if someone registers for you, and your foreign tax ID if applicable.
Is the RFC the same as the CURP?
No. The CURP is a personal ID number you get with your residency card; the RFC is a tax ID you register for with SAT.
Sources & official references
This page is general information, not legal or tax advice. Consulates interpret rules differently — confirm with your consulate or a licensed professional before acting.