The Constitution of Mexico does not declare an official language; however, Spanish is the de facto national language spoken by over 99% of the population^[1] making it the largest Spanish speaking country in the world. Due to the cultural influence of the United States, American English is widely understood, especially in border states and tourist regions, with a hybridization of Spanglish spoken.^[2][3] The government also recognizes 63 indigenous languages spoken in their communities out of respect, including Nahuatl, Mayan, Mixtec, etc.

The Mexican government uses solely Spanish for official and legislative purposes, but it has yet to declare it the national language mostly out of respect to the indigenous communities that still exist. Most indigenous languages are endangered, with some languages expected to become extinct within years or decades, and others simply having populations that grow slower than the national average. According to the Commission for the Development of Indigenous Peoples (CDI) and National Institute of Indigenous Languages (INALI), while 9% of the population identifies as belonging to an indigenous group, around 5-6% speak an indigenous language.

From the arrival of the first Franciscan missionaries, Spanish, Latin, and indigenous languages played parts in the evangelization of Mexico. Many sixteenth-century churchmen studied indigenous languages in order to instruct native peoples in Christian doctrine. The same men also found Castilian and Latin appropriate in certain contexts. All told, there existed a kind of "linguistic coexistence" from the beginning of the colonial period.^[4]

Some monks and priests attempted to describe and classify indigenous languages with Spanish. Philip II of Spain decreed in 1570 that Nahuatl become the official language of the colonies of New Spain in order to facilitate communication between the natives of the colonies.^[5]

In 1696 Charles II reversed that policy and banned the use of any languages other than Spanish throughout New Spain.^[5] Beginning in the 18th century, decrees ordering the Hispanization of indigenous populations became more numerous and Spanish colonizers no longer learned the indigenous languages.

After independence the government initiated an educational system with the primary aim of Hispanization of the native populations. This policy was based on the idea that this would help the indigenous peoples become a more integrated part of the new Mexican nation.^[6][7]

Except for the Second Mexican Empire, led by the Habsburg Maximilian I, no Mexican government tried to prevent the loss of indigenous languages during the 19th century.^[6]

The 1895 census records some 16% of the populace spoke various indigenous languages "habitually," while 0.17% did foreign languages. The rest, 83.71%, spoke primarily Spanish instead.^[8]

For most of the 20th century successive governments denied native tongues the status of valid languages. Indigenous students were forbidden to speak their native languages in school and were often punished for doing so.^{[6][7][9][10][11][12]}

In 2002, Mexico's constitution was amended to reinforce the nation's pluricultural nature by giving the State the obligation to protect and nurture the expressions of this diversity. On June 14, 1999, the Council of Writers in Indigenous Languages presented Congress with a document entitled "Suggested legal initiatives towards linguistic rights of indigenous peoples and communities", with the goal of beginning to protect the linguistic rights of indigenous communities. La Ley General de Derechos Lingüísticos de los Pueblos Indígenas was passed in March 2003, establishing a framework for the conservation, nurturing and development of indigenous languages. Critics claim that the law's complexity makes enforcement difficult.^{[13][14][15][16][17]}

Spanish is the de facto national language spoken by the vast majority of Mexicans, though it is not defined as an official language in legislation. The second article of the 1917 Constitution defines the country as multicultural, recognizes the right of the indigenous peoples to "preserve and enrich their languages" and promotes "bilingual and intercultural education".

In 2003, the Mexican Congress approved the General Law of Linguistic Rights of the Indigenous Peoples (Ley General de Derechos Lingüísticos), which is a law that recognizes that Mexico's history makes its indigenous languages "national languages".^[18] Accordingly, they "have the same validity [as Spanish] in their territory, location and context". At the same time, legislators made no specific provisions for the official or legal status of the Spanish language. This law means that indigenous peoples can use their native language in communicating with government officials and request official documents in that language. The Mexican state supports the preservation and promotion of the use of the national languages through the activities of the National Institute of Indigenous Languages.^[19][20][21]

Mexico has about six million citizens who speak indigenous languages. That is the second-largest group in the Americas after Peru. However, a relatively small percentage of Mexico's population speaks an indigenous language compared to other countries in the Americas, such as Guatemala (42.8%), Peru (35%), and even Ecuador (9.4%), Panama (8.3%),^[22] Paraguay and Bolivia.

The only indigenous language spoken by more than a million people in Mexico is the Nahuatl language; the other Native American languages with a large population of native speakers (at least 400,000 speakers) include Yucatec Maya, Tzeltal Maya, Tzotzil Maya, Mixtec, and Zapotec.

According to the Law of Linguistic Rights, Mexico recognizes sixty-two indigenous languages as co-official National languages.^[23] With Spanish being the dominant language, Mexico has become a site for endangered languages. "Indigenous people’s disadvantaged socioeconomic status and the pressure of assimilation into mestizo society have been influential on indigenous language loss."^[24] The result of the conflict between indigenous languages and Spanish has been a language shift in Mexico from indigenous languages being spoken to more people using Spanish in every domain. Due to this situation there have been many language revitalization strategies implemented in order to create a language shift to try to reverse this language shift. Literature projects done with the Nahua people ^[25] include "Keeping the fire alive: a decade of language revitalization in Mexico" showing the experiences of language revitalization in South Mexico.^[26]

The deaf community uses Mexican Sign Language, Mayan Sign Language, and, particularly among Mexicans who attended school the United States, American Sign Language. Other local sign languages are used or emerging, including Albarradas Sign Language, Chatino Sign Language, Tzotzil Sign Language, and Tijuana Sign Language.^[27][28]

The non-Spanish and non-indigenous languages spoken in Mexico include English (by English-speaking as well as by the residents of border states). One example of this group is of the American Mormon colony of Nueva Casas Grandes in Chihuahua, which settled in the late 19th century. Afro-Seminole Creole, an English-based creole, is traditionally spoken by the Mascogos of Coahuila. Korean is spoken mainly in Nuevo León. German (spoken mainly in Mexico City and Puebla), Greek (spoken mainly in Mexico City, Guadalajara and especially in Sinaloa state), Arabic, Venetian (in Chipilo), Italian, French, Occitan, Catalan, Basque, Galician, Asturian, Filipino, Polish, Hebrew, Korean, Ladino, Plautdietsch, Armenian, Japanese, Chinese and other languages are spoken by smaller numbers. Some of these languages (Venetian and Plautdietsch) are spoken in isolated communities or villages. The rest are spoken by immigrants or their descendants who tend to live in the larger cities and towns.

As far as second languages go, many educated Mexicans (and those with little education who have immigrated to the US and returned) have different degrees of fluency in English. Many Mexicans working in the tourist industry can speak some English.^[29]

A study conducted by the Alliance française in 2019 revealed that Mexicans have begun to take a greater interest in studying the French language, with 250,000 people being French speakers and 350,000 learning French.^[30]

Romani is spoken by the Mexican Roma minority.^[31]

• List of Mexican states by indigenous-speaking population
• Pura López Colomé