What SINNA is
SINNA is SRE’s system for nationality and naturalization. You pre-register your details in it, choose where you want to be attended — the Oficina Central in Mexico City or one of the Módulos de Atención al Público — and pick a day and time from a calendar. The reference number for your appointment arrives by email at the address you entered.
It only works on a computer. Not a phone, not a tablet. This one detail is responsible for a large share of the frustration people report with the system.
It is free, and the scams are predictable
SRE states plainly that the appointment to start the naturalization process is a free procedure, and that it does not grant appointments manually, through gestores, or through outside internet sites.
That is worth repeating because this is the point in the process where money gets taken. If someone offers you a guaranteed slot, a faster slot, or a slot at all in exchange for a fee, they are selling you something the government gives away. Pay the MXN 9,500 federal fee at a bank, and pay nobody for the appointment.
SRE also warns that giving false information in the pre-registration cancels the appointment, and that false statements can be treated under Article 247 of the Código Penal Federal. Fill it in exactly as your documents read.
Have this ready before you start
- Your name exactly as it appears on your resident card and birth certificate, accents included.
- Your CURP, from your resident card.
- An email address you check. The reference number goes there and nowhere else.
- The place you want to be attended, decided in advance. Where the exam is given
- A rough idea of your dates. Slots go, and going back for a second pass costs you the good ones.
Start from SRE’s own page rather than a search result: Obtención de cita para iniciar el trámite de naturalización.
When slots open
Appointment availability is released in batches rather than continuously, which is why Spanish-language migration sites publish a "when do the appointments for next month open" post every month. Those posts are useful and perishable in equal measure.
Two things are durable: check the calendar in SINNA itself rather than relying on a third party’s summary, and be ready to book the moment you find a slot — with your details and your chosen office decided in advance, booking takes a minute rather than an evening.
After you book
- Pay the MXN 9,500 fee at a certified bank or through its website, and keep the original receipt.
- Assemble the file. The apostille and the perito traductor translation are the two steps with the longest lead times, so start them first. Documents
- Study. The gap between booking and the appointment is the study window you actually have.
- Turn up with everything. What happens on the day
Questions people ask
Can I do the SINNA pre-registration on my phone?
No. Pre-registration only works on a computer. It is the single most common reason people get stuck at this step.
How much does the appointment cost?
Nothing. SRE says the appointment is free and that it does not grant appointments through gestores or external websites. The MXN 9,500 you pay is the federal fee for the application itself, paid at a bank.
What if I make a mistake in the pre-registration?
Correct it rather than leaving it. SRE warns that false information cancels the appointment, and a mismatch between your form and your documents is a problem you do not want to discover at the counter.
Which SINNA address is the real one?
Reach SINNA through the link on SRE’s own appointment page. Current results show the system on more than one host, and in a trámite that attracts scams the official page is the safe way in.
Do I pay the fee before or after the appointment?
Before. Bring the original receipt with you. What it costs