How Voting Works in Mexico

Mexico's electoral system blends presidentialism, proportional representation, and distinctive institutional safeguards.

🗓️ Election Cycle

• President: Single 6-year term (sexenio), no re-election. Elected first Sunday in July every 6 years (next: 2024, 2030...).
• Congress: Bicameral — Senate (128, 6-year) + Chamber of Deputies (500, 3-year). Midterms at 3 years.

🗳️ Voting System: Mixed-Member Proportional

Chamber of Deputies (500 seats)

• 300 — First-past-the-post in single-member districts
• 200 — Proportional representation (plurinominal) from 5 regional lists (40 each)
• Threshold: Parties need ≥2% national vote for PR seats
• Cap: No party >300 total seats; over-representation limited to 8% above vote share

Senate (128 seats)

• 64 — Two per state (32 states), plurality winner
• 32 — Two per state, first minority (runner-up)
• 32 — National PR list
• 5 — Indigenous representatives (since 2024 reform)

👤 Voter Requirements

• Age 18+, Mexican citizen
• Valid credencial para votar (photo voter ID — issued by INE)
• Automatic registration for residents; expatriates register separately

📋 Election Day

Polls: 8 AM – 6 PM. Paper ballots, marked behind screen, deposited in transparent boxes. Preliminary results (PREP) same night; official count (cómputos distritales) days later.

🔁 Runoff?

No presidential runoff. Plurality wins. (Constitutional amendment would be required to change.)

🏛️ Institutional Guardian

INE (Instituto Nacional Electoral) — Autonomous, professionalized electoral management body (formerly IFE). Oversees registration, districting, funding, debates, results.

Mexico's system aims to balance governability (presidential majority) with pluralism (PR Congress)—a continuous calibration.