How to Read a Mexican ID Card: INE, Passport & Matrícula Consular

To read a Mexican ID card, start with the printed fields on the front (name, address, gender, birthdate, expiration), then decode the two 18-character strings that carry the real detail: the CURP and, on the INE voter credential, the Clave de Elector. Both codes pack the holder’s name initials, exact date of birth, gender, and state of birth into a fixed pattern you can pick apart character by character. Most cards you’ll encounter are INE credentials, so that’s where the coded information is densest.

Three documents cover nearly everything you’ll see. The INE credential (credencial para votar) is issued by Mexico’s National Electoral Institute and works as the de facto national ID, used far more often for everyday identification than for voting. The Mexican passport is available in one, three, six, or ten-year validity periods.¹ The Matrícula Consular is issued by Mexican consulates to nationals living abroad and is valid for five years.²

What’s Printed on the Front of an INE Card

The photo sits on the left. Personal information runs to the right and below it, in these fields:

Nombre / Apellidos. Full legal name. Mexican naming convention lists two surnames: the paternal surname (apellido paterno) first, then the maternal surname (apellido materno).
Domicilio. The registered home address.
Sexo. H for hombre (male) or M for mujer (female).
Fecha de nacimiento. Date of birth, always day/month/year. “15/03/1988” is March 15, 1988, not the other way around.
Sección. The electoral section number tied to the voter’s address. The same four digits open the card number.
Vigencia / Año de emisión. Year of issuance and expiration year. Under reforms adopted in 2007, INE credentials are valid for ten years from issuance.³
Clave de Elector. An 18-character voter identification code.
CURP. The 18-character national population registry code.

Older INE cards also carry a small number indicating how many times the credential has been issued to that person: 00 for the first card, 01 for a first replacement, 02 for a second, and so on. That tells you whether you’re looking at an original or a reissue.

What’s on the Back of an INE Card

The reverse side has changed. Older cards showed the fingerprint and signature on the back. Cards issued from late 2019 onward moved that data into digital form: no visual personal information, just machine-readable zones, barcodes, and two QR codes.

The QR codes are the fastest verification tool you have. Scan them with the free Valida INE-QR app, developed by the National Electoral Institute. A successful scan confirms the credential was genuinely issued by the INE and displays the encoded personal data so you can compare it against the printed front.⁴ The app works on credentials issued from December 2019 onward. On older cards, QR scanning won’t apply.

How to Decode the CURP

The Clave Única de Registro de Población is an 18-character code assigned to every Mexican citizen and resident. It functions like a national ID number, but the characters themselves reveal personal details instead of being random.⁵ The CURP appears on the INE credential, on Mexican passports, and on most other official documents.

Take a sample CURP of GARC850315HDFRRL09. Here’s what each position means:

Characters 1–2 (GA): the first letter and first interior vowel of the paternal surname. For “García,” G and A.
Character 3 (R): first letter of the maternal surname.
Character 4 (C): first letter of the first given name.
Characters 5–10 (850315): date of birth as YYMMDD. Here, March 15, 1985.
Character 11 (H): gender. H for male, M for female.
Characters 12–13 (DF): two-letter code for the state of birth. DF stood for Distrito Federal, now Ciudad de México and coded CM on newer records. Each of Mexico’s 32 states has its own code.
Characters 14–16 (RRL): the first interior consonant of the paternal surname, maternal surname, and first name, in that order.
Character 17 (0): a letter or number assigned by RENAPO, Mexico’s National Population Registry, to prevent duplicate CURPs when two people share the same name and birth data.
Character 18 (9): a check digit calculated by RENAPO to validate the code.

So from 18 characters you can extract the person’s approximate name, exact birthdate, gender, and birthplace. When you’re verifying an ID, checking whether the CURP matches the printed name and birthdate fields is a quick way to catch inconsistencies.

How to Decode the Clave de Elector

The Clave de Elector is a separate 18-character code found only on the INE credential. It resembles the CURP and encodes overlapping data, but it’s a voter-specific identifier. The pattern:

Characters 1–6: letters from the holder’s name. Specifically, the first letter and first internal consonant of the paternal surname, then the same pair for the maternal surname, then the same pair for the given name.
Characters 7–12: date of birth in YYMMDD format.
Characters 13–14: two-digit code for the state of birth.
Character 15: gender (H or M).
Characters 16–17: a random number to prevent duplication.
Character 18: a check digit.

Because the Clave de Elector and CURP encode some of the same information twice, comparing them is another quick validity check. If the birthdate embedded in one doesn’t match the other, something’s wrong with the document.

Reading an RFC When It Appears

The Registro Federal de Contribuyentes is Mexico’s federal taxpayer ID. It won’t always sit on the ID card itself, but it turns up in financial and employment paperwork. For individuals, the RFC is 13 characters. For businesses, 12.⁶

An individual RFC uses the pattern that’s become familiar by this point: four letters from the name, six digits for the birthdate in YYMMDD, and a three-character homoclave (a unique alphanumeric suffix generated by algorithm to prevent duplicates). The name portion uses the first letter and first vowel of the paternal surname, the first letter of the maternal surname, and the first letter of the given name. If you’ve already decoded the CURP, the first four letters of the RFC should match the first four characters of the CURP.

Reading a Mexican Passport

The data page shows the same core information as the INE card: full name, date of birth, gender, place of birth, and a photograph. It also shows the date of issuance, expiration date, passport number, and issuing authority. Validity can be one, three, six, or ten years.¹

The CURP is printed on the data page, so the decoding above applies here too. At the bottom of the page, two lines of machine-readable text (the MRZ) encode the holder’s name, passport number, nationality (MEX), date of birth, gender, and expiration date in the format border-control scanners read. Mexico has also issued passports with an “X” gender marker for non-binary individuals.

Reading a Matrícula Consular

The Matrícula Consular front shows the holder’s full name, date of birth, place of birth, photograph, and signature. It also carries a unique registration number, the name of the issuing consulate, and the issuance and expiration dates. Every Matrícula Consular is valid for five years.²

Because it’s issued specifically to Mexican nationals living outside Mexico, the card also records the consular district of registration. It proves Mexican nationality; it does not by itself prove immigration status in the United States or anywhere else.

Spotting a Fake

All three documents carry physical security features that make counterfeiting difficult. What to look for:

Holograms. Tilt the card and watch for images or colors that shift with the angle. The INE credential has a holographic overlay visible under direct light.
Microprinting. Tiny text worked into the design, hard to read without magnification and nearly impossible to replicate on a consumer printer.
UV features. Under ultraviolet light, genuine documents reveal hidden patterns, text, or images not visible in normal lighting.
Tactile elements. Run a finger across the card. Raised printing or embossed areas add a physical dimension a flat reproduction can’t fake.
Guilloche patterns. The interlocking curved lines in the background design, a classic anti-counterfeiting measure used on currency and IDs worldwide.

For newer INE credentials, the fastest authentication is the QR scan through the Valida INE-QR app. A successful scan confirms INE issuance and lets you compare the encoded data against the printed side.⁴ If the scan fails or the data doesn’t match, treat the document with skepticism.

Checking the Expiration

The most common oversight is skipping the expiration date. Each document has its own window:

INE credential: valid for ten years from the year of issuance, with the expiration year printed on the front. Cards issued before the 2007 reforms may show unlimited validity, and the INE has been phasing those out through replacement drives.³
Mexican passport: expiration is printed on the data page. Validity depends on the period chosen at issuance (one, three, six, or ten years).¹
Matrícula Consular: valid for five years, with issuance and expiration dates on the card. Consulates will not accept expired Matrícula Consular cards issued before 2005 as supporting documentation for a new one.²

An expired Mexican ID may still confirm identity in informal settings, but it generally won’t clear official transactions, border crossings, or new financial accounts.

1
sre.gob.mx. PASSPORT
2
Consulado General de México en San Diego. Consular Identification Card
3
Instituto Nacional Electoral – INE. Electoral Registry
4
Google Play. Valida INE-QR
5
Microsoft Learn. Mexico Unique Population Registry Code (CURP) Entity Definition
6
SAT. Inscripción y Avisos al Registro Federal de Contribuyentes (RFC) para Personas