A federal state. "The States shall adopt for their internal government, the popular, representative and republican form of government, with the free municipality as the basis of their territorial division and political and administrative organization." (Art. 115, Constitution of the United Mexican States). The country is divided into 31 states and a Federal District. As of 2008, Mexico was comprised of 2,437 municipalities.

El poder legislativo de los Estados Unidos Mexicanos se deposita en un Congreso bicameral, compuesto por una cámara de diputados y otra de senadores. Se integra por quinientos (500) diputados, trecientos (300) electos por mayoría relativa en los 300 distritos electorales del país (uninominales) y docientos (200) electos por el sistema de representación proporcional (plurinominales). La Cámara de Senadores se integrará por ciento veintiocho (128) senadoras y senadores

"Each municipality shall be governed by a municipal council chosen through direct election by the people... there shall be no intermediate authority between the [municipal council] and the State. Mayors, councilpersons and municipal representatives chosen directly by the people may not be re-elected for a consecutive term." (Art.115).

Terms last three years.

Majority for mayors; proportional for city and municipal councils. All state electoral laws provide for a mixed system (with the exception of municipal elections governed by customary law); that is, they are governed by a system which combines the majority and proportional methods. The number of members elected to a municipal council is determined by the Organic Law of the Municipal System or the Organic Law of the Federal District, as the case may be. With regard to the election of councilpersons in metropolitan districts - in the numbers specified by the Organic Law of the Municipal System - the provisions of this Law apply.

Closed party lists.

Uninominal for mayors; plurinominal for councilpersons.

Decree 135 of 2014 modifies article 41 of the Political Constitution of the United Mexican States to raise gender parity to the constitutional level in the electoral arena, for candidatures to the Federal and local Congress.

Organic Law of the Municipal System; Constitution, Title Five: Of the States of the Federation and the Federal District (amended by executive order published in the official Federation journal on 25 October 1993); Constitution, Article 115.

"Except for the provisions in section II of Article 105 of this Constitution, the Electoral Tribunal shall be the highest adjudicatory authority on the subject, and shall constitute a specialized body of the Judicial Branch of the Federation." (Constitution, Art. 99). The institutions responsible for electoral matters at the federal level are the Federal Electoral Institute (IFE), the Electoral Tribunal of the Judicial Branch of the Federation and the Special Prosecutor for Electoral Offences. The institutions responsible for overseeing electoral matters at the municipal level are the state electoral agencies and the local electoral courts.