--- title: "The Article 123 reform: 40 hours in the Constitution · Sicheca" description: "What changed in the Constitution on March 3, 2026 and how it relates to the Federal Labor Law." url: https://sicheca.com/en/blog/reforma-al-articulo-123-jornada-de-40-horas lang: en alternate_es: https://sicheca.com/blog/reforma-al-articulo-123-jornada-de-40-horas.md --- Law and fines · 3 min read # The reform to article 123: 40 hours in the Constitution Short answer On March 3, 2026, Article 123 of the Constitution was amended to set the 40-hour workweek and prohibit overtime for people under 18. The details were left to the Federal Labor Law, amended on May 1. ## Two reforms, one change - The Constitution sets the principle. - The law sets the timetable, overtime, the record and the fine. ## Why the order matters Because a constitutional change is harder to reverse than a legal one. ## The reform in one minute The reform has two parts. On March 3, 2026, article 123 of the Constitution was amended to set the 40-hour workweek. On May 1, 2026, the Federal Labor Law was amended, which is where the detail is. - The maximum working week drops from 48 to 40 hours, two hours per year, between 2027 and 2030. - Overtime has a weekly cap: it is paid at double time up to the cap and at triple time for up to 4 more hours. - Each company must electronically record the start and end time of each person's workday. - Not keeping that record is fined 250 to 5,000 UMA. - Salary and benefits cannot go down because of the reduction in hours. What remains pending are the STPS general rules, which will define who the record applies to and what exceptions there will be. They take effect on January 1, 2027. | Year | Maximum working hours | Double-time overtime | Triple-time overtime | | --- | --- | --- | --- | | 2026 | 48 h | 9 h | 4 h | | 2027 | 46 h | 9 h | 4 h | | 2028 | 44 h | 10 h | 4 h | | 2029 | 42 h | 11 h | 4 h | | 2030 | 40 h | 12 h | 4 h | Decree published in the Official Gazette of the Federation on May 1, 2026, second and fourth transitory provisions, and article 68 of the LFT. Each change applies from January 1. ## Common mistakes - Assuming the obligation does not apply because you are a small business. - Believing a device or fingerprint is required. - Confusing the date the law took effect with the date of the STPS rules. - Reading the 2030 caps as if they already applied. - Trusting a provider that claims to be certified by the authority. ## What to do now 1. Read what article 132, section XXXIV, requires. 2. Review how you record your staff's clock-in and clock-out today. 3. Choose an electronic recording method. 4. Agree on it in writing with each person. 5. Check the STPS general rules when they are published. ## Related terms **[Vacations by law: how many days are owed](https://sicheca.com/en/blog/vacaciones-por-ley).** With one year of work, 12 days of vacation are owed. **[IMSS contributions: what they are and who pays them](https://sicheca.com/en/blog/cuotas-del-imss).** Employer-employee contributions are the payments to the IMSS that fund social security. **[What is attendance control](https://sicheca.com/en/blog/control-de-asistencia).** Attendance control is any means of knowing who came to work and at what time. ## Frequently asked questions ### Which section was amended? Section A, subsections IV and XI. ### Who monitors compliance? The Ministry of Labor and Social Welfare, through inspections. ### Where do I find the official text? In the Official Gazette of the Federation of May 1, 2026 and in the current version of the Federal Labor Law published by the Chamber of Deputies. ### Does this replace the advice of a lawyer? No. It is general information. For decisions about your company, consult a labor lawyer. ### Does the law require a particular system? No. It asks that the record be electronic and include the start and end time for each person. ## Legal basis and sources - Fines: articles 992, 994 and 1002 of the LFT. - Working hours: articles 58 to 64 of the LFT and second transitory provision of the decree. - Article 123, section A, of the Constitution, amended on March 3, 2026. - [Decree amending the Federal Labor Law on the reduction of the working week](https://sidof.segob.gob.mx/notas/docFuente/5786537). Official Gazette of the Federation, May 1, 2026. - [Federal Labor Law, current text](https://www.diputados.gob.mx/LeyesBiblio/pdf/LFT.pdf). Chamber of Deputies. **How we write this content.** The Sicheca team writes it from the official text of the law. When something is not yet defined by the authority, we say so. It is general information and does not replace the advice of a lawyer or an accountant. ## Keep reading [ Law and fines **Confidential employees: do they also record their working time?**](https://sicheca.com/en/blog/trabajadores-de-confianza-y-registro-de-jornada) [ Law and fines **Overtime lawsuit: who has to prove the workday**](https://sicheca.com/en/blog/juicio-por-horas-extra-quien-prueba-la-jornada) [ Law and fines **How long do working-time records have to be kept?**](https://sicheca.com/en/blog/cuanto-tiempo-conservar-los-registros-de-jornada) [ Glossary **What the UMA is and how much it is worth**](https://sicheca.com/en/blog/que-es-la-uma-y-cuanto-vale) [See all articles](https://sicheca.com/en/blog/) Who publishes this blog Sicheca is a digital time clock for recording working time from your phone. We write these guides from the official text of the law, so any business can understand what applies to it. If you want to try it, there is a waitlist. [Join the waitlist](https://sicheca.com/en/lista-de-espera?utm_source=blog&utm_medium=articulo&utm_campaign=reforma-al-articulo-123-jornada-de-40-horas&utm_content=final)