This previous Penal Code from 1872 was replaced in 1929. The new legal order aimed to modify the legal architecture of the Porfirio Díaz dictatorship, which was based on penal repression, to align it with the context of the constitutional guarantees and social justice proclaimed by the Mexican Revolution of 1910.

Once again, any notion of homosexuality (both male and female) was formally excluded from the document. The potential criminalization allowed by the previous code due to the vagueness of the sanctions related to 'offenses against public morality and good customs' is now technically limited solely to a prohibition of pornography. Thus, Article 536 536 (Second Book; Title 8 'Crimes against Public Morality'; Chapter I 'Offenses against Public Morality or Good Customs') mentions imprisonment and fines for those who reproduce or manufacture obscene writings, images, or objects, as well as for those who display or commercialize such obscene expressions in public.

Again, in 1931, the penal code was substituted by the one that still governs at the federal level today. However, in 1966, Article 201 (Third Book; Title 8 'Crimes against Public Morality and Good Customs'; Chapter II 'Corruption of Minors') was reformed, and for the first time, a reference to homosexuality appeared. It established imprisonment for anyone who induces or incites a minor under 18 years old to engage in 'homosexual practices.' The penalty was doubled if the act was repeated and resulted in the minor 'acquiring habits of homosexual practices.'

Finally, those last provisions that indirectly incited the criminalization of homosexuality were eliminated in the 1999 reform.

The congress of Mexico’s northeastern border state Tamaulipas has voted to recognise same-sex marriage, making it legal across the country.

Becoming the last of the country’s states to do so, Tamaulipas amended the state’s Civil Code on Wednesday, setting off cheers of “Yes, we can!” from supporters of the change.

In Mexico, there are no laws restricting the discussion or promotion of LGBTQ+ topics since the removal of all mentions of homosexuality in Article 201, which prohibited "corrupting minors" with habits that included homosexuality on the federal level.

However, some states still contain homosexuality as a "corrupt habit" to showcase to minors.

In 2004, Mexico City became the first region of Mexico to provide legal gender recognition.

In 2009, the Supreme Court of Mexico established in its Judgment No. 6/2008 (2009) that the right to personal identity and free development of personality includes the right to gender identity and to "sexual reassignment", which obliges states to provide access to the "rectification of name and sex legal markers".
In 2018, the Court issued Judgment No. 1317/2017 (2018) where it analysed the most appropriate procedure to guarantee "sex-gender rectification in the Civil Registry". In summary, this judgment concluded that the type of authority (judicial or administrative) before which the procedure is conducted is irrelevant as long as the nature of the procedure is materially administrative. Specifically, it must (a) be comprehensive; (b) be based on free and informed consent, with no medical, psychological and/or pathologising requirements; (c) be confidential; (d) be expeditious and free of charge; and (e) it must not require surgical or hormonal treatments. Despite this, various Mexican states have not unified their regulations and, in many cases, continue to require judicial processing and all sorts of evidence.

There are no government restrictions placed on gender-affirming care and government guidelines for public health institutions endorse medical intervention with transgender youth. However availability proves a problem in many areas.

In 2023, Mexico recognized gender X on all forms of ID including passports. Drivers’ licenses are yet to come with this change as they rely on state laws.

Since 2009, several states and Mexico City have been adding gender identity as a protected characteristic to its anti discrimination laws. Sexual orientation remains protected under federal Mexican law.

Since 2003, the Federal Law to Prevent and Eliminate Discrimination has defined in Article 9, sections III and IV, the following as acts of negative discrimination:
• Prohibiting the free choice of employment or restricting opportunities for access, retention, and promotion within it.
• Creating differences in wages, benefits, and working conditions for equal work.
This is directly related to sexual orientation, as the former Article 4 of this law (renumbered as Article 1, section III after the 2022 reform) explicitly includes it as a basis for potential discrimination.

Subsequently, in 2014, section V was added to the same Article 9, stating that creating differences in wages, benefits, and working conditions for equal work is also considered another act of negative discrimination.

In 2012, Article 2 of the Mexican Federal Labour Law was amended to explicitly include sexual orientation in the list of factors for which employers, both public and private, must not discriminate against their workers. This reform aimed to foster dignified working environments that uphold human dignity.
Similarly, Article 3 was also revised to state that work is a right and a social responsibility; it is not a commodity. Therefore, no discriminatory practices based on workers' sexual orientation may be allowed.
Likewise, since then, Article 56 has stipulated that working conditions may never be less favourable than those established by the Law and must be proportional to the importance of the services provided and equal for equal work, with no differences or exclusions based on sexual orientation.

Since 2009, states have been provided further protections based on gender identity.

Article 1(3) of the Federal Act to Prevent and Eliminate Discrimination (2003) includes “sexual preferences” as one of the prohibited grounds of discrimination. This law applies to housing as per Article 9(XXI). Gender identity is not explicitly mentioned but some states provide protections on the basis of gender identity as well since 2009.

There is no federal law allowing for joint adoption and second parent adoption by same-sex couples. Adoption is only permitted for same sex married couples in 21 of the 31 Mexican states and Mexico City

On May 31st 2025, Tamaulipas became the first state in Mexico to ban surgery on intersex infants.

Since 2012, LGBTIQ+ people are permitted to serve openly in the Mexican military.

NOM 253 removes targeted restrictions on blood donations from gay and bisexual men. Instead, it prohibits donations from individuals with HIV or hepatitis, their partners, and those who participate in "high-risk sexual practices," irrespective of their sexual orientation.

Conversion therapy is a federal offence under Article 209 Quintus of the Federal Penal Code (Código Penal Federal) and Article 465 Ter of the General Health Law (Ley General de Salud).

Conversion therapy is defined as any treatment, service, therapy, or practice intended to obstruct, restrict, impede, diminish, annul, or suppress sexual orientation or gender identity/expression.

Those liable under the law include anyone who practices, conducts, imparts, applies, forces, or funds such activities.

Sanctions include:
- 2 to 6 years in prison and a fine of 2,000 UMA (Unidad de Medida y Actualización, a unit updated yearly based on inflation. In 2024, 2,000 UMA exceeded $11,000 USD).
- Sanctions are doubled if the victim is a minor (-18), an elderly person (+60), or a person with a disability; or if the perpetrator is a public/government employee, or they have any relationship with the victim (such as family member; or employer, teacher, medical professional, doctor, nurse, or psychologist). Additionally, the latter will face professional dismissal, disqualification, and suspension (1 to 3 years or equivalent to the prison sentence).
- Sanctions are further doubled if any kind of violence (physical, psychological, or moral) is used against the victim.

Illegal with a minor under 12, ambiguous rulings observed 12-18, universally legal 18+.