|Number of teams||14|
|Levels on pyramid||2|
|Promotion to||Liga MX|
|Relegation to||Segunda División|
|Domestic cup(s)||Copa MX|
|Current champions||Tecos (1st Title)
|TV partners||TVC Deportes
Ascenso MX (Promotion MX) is the second professional level of the Mexican football league system. The champion of the competition is promoted to Liga MX (top-flight division). The bottom team gets relegated to Segunda División de México (the third tier).
Formerly known as Primera División A (First Division A) the league changed its name and competition format in 2009 to Liga de Ascenso. It was rebranded as Ascenso MX in 2012. The main changes are that clubs now do not need a FMF certification to get promoted and that the competition doesn't use group stages.
In 1994, in order to create a premier league, the Mexican Football Federation decided to upgrade the Second Division to "Primera División A" (First Division A) to bring closer together the level of play in the two tiers, Primera and Primera A. The project was under the direction of José Antonio García Rodríguez, president of the top-tier Primera Division at the time. He envisioned the new division to be joined by the best teams of the Segunda and include teams from the United States (Los Angeles Salsa and San Jose Black Hawks expressed desire to join). Upon review, FIFA did not authorize such integration. As a result the new league was created instead with the best Second Division teams. The 1994-1995 season began with 15 teams: Acapulco, Gallos de Aguascalientes, Club Celaya, Irapuato FC, C.F. La Piedad, Club Deportivo Marte, C.F. Pachuca, Atlético San Francisco, San Luis F.C., Lagartos de Tabasco, Coras de Tepic, Inter de Tijuana, Halcones de Querétaro, Venados de Yucatán and Zacatepec. Cobras de Ciudad Juárez, which would have been the sixteenth team, declined to participate due to financial problems.
During the 2006 tournament it was decided to increase the number of teams from 20 to 24 and it was also decided to form two groups, A and B divided by geographical areas.
In 2009 major changes occurred the most prominent being the name change from Primera Division A to Liga de Ascenso. The league was reduced to 17 teams and eliminated the groups. Starting with the Apertura 2010 season 18 teams participated. In 2012 the league was rebranded as Ascenso MX. The Guerreros de Oaxaca will be the 16th team of Ascenso MX starting 2013-2014 season. The Guerreros will be composed of the former Segunda Division team Tecamachalco which had won ascendency into Ascenso MX in 2012, but did not fulfill infrastructural requirements set by Mexican Football Federation. Zacatepec will also be promoted to the Ascenso MX taking the spot of Pumas Morelos in August 2013. 
Beginning of 2014-15 Season, Ascenso MX will not relegate a team to Second Division of Mexico.
|Altamira||Sergio Orduña||Altamira, Tamaulipas||Altamira||13,500|
|Atlante||Gastón Obledo||Cancún, Quintana Roo||Andrés Quintana Roo||20,000|
|BUAP||Ricardo Valiño||Puebla, Puebla||Olímpico de la BUAP||21,750|
|Celaya||Jorge Torres||Celaya, Guanajuato||Miguel Alemán||33,340|
|Correcaminos||Omar Arellano||Ciudad Victoria, Tamaulipas||Marte R. Gómez||18,000|
|Irapuato||Roberto Sandoval||Irapuato, Guanajuato||Sergio León Chávez||33,000|
|Mérida||Juan Carlos Chávez||Mérida, Yucatán||Carlos Iturralde||18,000|
|Necaxa||Miguel de Jesús Fuentes||Aguascalientes, Aguascalientes||Victoria||25,494|
|Oaxaca||Ricardo Rayas||Oaxaca,Oaxaca||Benito Juárez||12,000|
|San Luis||Flavio Davino||San Luis Potosi, San Luis Potosí||Alfonso Lastras||30,000|
|Dorados de Sinaloa||Diego Torres||Culiacán, Sinaloa||Banorte||23,000|
|Tepic||Joel Sánchez||Tepic, Nayarit||Arena Cora||12,945|
|Zacatecas||Pablo Marini||Zacatecas, Zacatecas||Francisco Villa||18,000|
|Zacatepec||Ignacio Rodríguez||Zacatepec, Morelos||Agustín Díaz||26,000|
Titles By Club
|Irapuato||4||Invierno 1999, Verano 2000, Apertura 2002, Clausura 2011|
|León †||4||Verano 2003, Clausura 2004, Clausura 2008, Clausura 2012|
|Querétaro †||3||Clausura 2005, Clausura 2006, Apertura 2008|
|La Piedad ††||2||Verano 2001, Apertura 2012|
|Necaxa||2||Apertura 2009, Clausura 2010|
|Dorados de Sinaloa||2||Apertura 2003, Clausura 2007|
|Puebla †||2||Apertura 2005, Apertura 2006|
|Tigres UANL †||2||Invierno 1996, Verano 1997|
|Pachuca †||2||1995-96, Invierno 1997|
|U. de G. †||1||Apertura 2013|
|Tecos †††||1||Clausura 2014|
|Neza †††||1||Clausura 2013|
|Tijuana †||1||Apertura 2010|
|Indios †††||1||Apertura 2007|
|Veracruz †||1||Invierno 2001|
|Gallos de Aguascalientes †††||1||Invierno 2000|
|Unión de Curtidores ††||1||Verano 1999|
|Tigres B †††||1||Verano 1998|
|Venados de Yucatán †††||1||Invierno 1998|
† Teams in the First Division
†† Teams in the Second Division
Promotion and relegation
Relegation and Promotion by Club
- 1976–77: Tampico bought San Luis's spot in first division
- 1977–78: Deportivo Neza is bought Club de Fútbol Laguna and took its spot.
- 1981–82: Tampico bought Atletas Campesinos and took over its spot
- 1983–84: Ángeles de Puebla bought Oaxtepec and took over its spot
- 1988–89: Veracruz bought Neza and took over its spot
- 1992–93: U.T. Neza changes its name to Toros Neza
- 1998-99: Puebla bought U.D Curtidores and took over its spot
- 1999-00: Irapuato gained automatic promotion as they won both tournaments.
- 2001–02: Veracruz gained automatic promotion due to expansion in first division
- 2012-13: Veracruz bought La Piedad's spot in first division
- 2013-14: Zacatepec bought Cruz Azul Hidalgo's spot in Ascenso MX.
- "Nace la Liga de Ascenso". www.femexfut.org.mx. 2009-06-22. Retrieved 2009-06-22.
- Die 18 Mannschaften in der Liga de Ascenso 2010/11 (Spanish; retrieved on May 27, 2010)
- "Atlante construirá nuevo estadio en Cancún". MedioTiempo.com. Retrieved 12 August 2013.