The 40-hour work week reform in Mexico It's now a reality. On May 1, 2026, President Claudia Sheinbaum enacted the decree amending the Federal Labor Law and initiating the transition to a 40-hour workweek. This reform is undoubtedly the change with the greatest immediate impact on businesses in recent years.
If your company operates in Mexico City or any other state in the country, you need to understand what's changing, when it's changing, and what the legal consequences of non-compliance may be. This guide analyzes each key aspect: the phased-in schedule, new obligations for employers, mandatory electronic registration, and applicable fines.
What does the Labor Reform Published on May 1, 2026 Establish?
The decree published in the Official Gazette of the Federation (DOF) on May 1, 2026, amends, adds to, and repeals various provisions of the Federal Labor Law. Specifically, it modifies Articles 59, 61, 66, 68, 69, and 71, and adds section XXXIV to Article 132, as well as section IV Bis to Article 994.
The main objective is to regulate the constitutional reform to article 123 that was published on March 3, 2026. With that constitutional change, Mexico established the maximum work week of 40 hours as a fundamental right.
The LFT decree specifies the following:
- The maximum ordinary daytime working hours will be 8 hours; the night shift, of 7 hours; and the mixed one, of 7.5 hours.
- The sum of ordinary and overtime hours may not exceed 12 hours a day.
- For every six days of work, the employer must grant at least a day of rest with full salary.
- Reductions in salaries, wages, or benefits as a result of this reform are prohibited.
In short, the law has already changed. What is being phased in is the maximum weekly working hours, not the effective date of the law itself.
Official Gradual Reduction Schedule: From 48 to 40 Hours between 2026 and 2030
One of the most important aspects of business planning is the phased reduction schedule. The decree is clear:
| Year | Maximum weekly working hours |
|---|---|
| 2026 (until Dec.) | 48 hours (adjustment period) |
| 2027 | 46 hours |
| 2028 | 44 hours |
| 2029 | 42 hours |
| 2030 | 40 hours |
The effective reduction begins January 1, 2027The period from May 1 to December 31, 2026, is an adaptation phase. During this time, the Ministry of Labor and Social Welfare (STPS) will collect, process, and evaluate data to monitor the implementation of the change.
This means that companies have until December 31, 2026 to prepare: update contracts, internal regulations, human resources policies and implement electronic registration systems.
New Obligations for Employers: What Every Employer Must Comply
The reform doesn't just reduce working hours. It also imposes specific and verifiable obligations on all employers. The most relevant are listed below:
1. Electronic Work Record (Article 132, Section XXXIV)
From January 1, 2027, all employers must implement an electronic attendance control system that accurately records the entry time, rest periods, and exit time of each worker.
This record has full legal validity as evidence in court, provided it has been agreed upon between the employer and the employee. In other words, if there is a labor dispute regarding overtime, the digital time clock will be the primary evidence.
The STPS will soon issue the general provisions on the acceptable formats and methods for this registration.
2. Updating Contracts and Internal Regulations
Individual and collective contracts that establish working hours exceeding the new limit must be modified before December 31, 2026. The same applies to internal work regulations and human resources policies.
This is a mandatory compliance action, not optional. Failure to update contracts exposes companies to labor lawsuits.
3. Express Prohibition of Reducing Wages
The decree is unequivocal: no employer may reduce an employee's salary, wages, or benefits as a justification or consequence of a reduction in working hours. Any attempt to do so will be considered a serious violation of labor rights. The affected employee may demand retroactive payments and even compensation.
4. Limit on Overtime Hours
With the reform, the limit on weekly overtime hours will be gradually increased until it reaches a maximum of 12 hours By 2030, all overtime will be paid at double the regular rate, regardless of the amount worked. The previous system, where the first 9 hours were paid at double the rate and subsequent hours at triple the rate, will be eliminated.
⚖️ Do you need to adapt your company's employment contracts before December 31, 2026? At Baráibar & Asociados, we help you comply with the reform without risk. Contact us today in Mexico City.
Fines and Penalties: How Much Can Non-Compliance Cost Your Company?
Article 994, section IV Bis, of the Federal Labor Law establishes economic penalties for failure to comply with the obligation of electronic work hour registration. The fines range from 250 to 5,000 Units of Measurement and Update (UMA).
In 2026 values, that equates to between $29,327.50 and $586,550 Mexican pesos for infringement.
It is important to note that these penalties are calculated per affected worker. A company with 50 employees in non-compliance could face a potential penalty of several million pesos.
In addition to the economic aspect, failure to comply with working hours limits can lead to:
- Immediate inspections from the Ministry of Labor.
- Individual labor demands for unpaid overtime.
- Nullity of contractual clauses that contravene the new law.
- Joint and several liability for substitute patterns in business groups.
📋 Don't wait for an inspection. At Baráibar & Asociados, our Labor Law specialists in Mexico City conduct preventative audits to protect your company before 2027 begins.
Impact on Night Shifts, Mixed Shifts and Rest Days
The reform also specifies the rules applicable to special working days and mandatory rest days:
Special days: The day shift has a maximum of 8 hours; the night shift, 7 hours; and the mixed shift, 7.5 hours. These provisions were already in the Federal Labor Law, but are now being aligned with the new weekly limit.
Weekly rest: For every six days worked, the employee is entitled to one day of rest with full pay. The debate on whether the reform automatically implies two days of rest per week is not definitively resolved in the decree, but it is an issue that will have to be addressed in collective bargaining agreements and internal policies.
Sunday premium: People who work on Sundays are entitled to an additional premium of at least 25% on the ordinary salary of regular working days.
Minors: The reform expressly prohibits underage workers from working overtime. This is a special protective provision that employers must implement immediately.
Electronic Registration: Which Technology Complies with the Law?
Section XXXIV of Article 132 establishes that registration must be electronic, but does not specify the type of technology. The STPS (Ministry of Labor and Social Welfare) will define the technical requirements soon. However, the most common systems that already comply with the spirit of the standard are:
- Biometric readers (fingerprint, facial recognition).
- Mobile applications with geolocation, for remote or field work.
- Smart card systems or chip-enabled credentials.
- Attendance management platforms integrated into the payroll system.
The key point is that the registration must be agreed between the worker and the employer, and the employer has the obligation to keep it and show it to the authority when required.
For the purposes of labor litigation, this electronic record will constitute conclusive proof of the actual duration of the workday. This benefits both workers, who can prove unpaid overtime, and employers, who can demonstrate compliance.
What about collective bargaining agreements and unions?
The reform has a direct impact on collective bargaining agreements (CBAs). Those that establish working hours exceeding the new limit will need to be reviewed and modified. In sectors with a strong union presence, such as manufacturing, transportation, commerce, and services, this will entail collective bargaining renegotiations.
The Federal Labor Law (LFT) establishes that working conditions cannot be diminished. Therefore, if a collective bargaining agreement (CBA) established benefits exceeding those mandated by law (more days off, better-paid overtime), those conditions remain in place. The reform sets a minimum standard, not a maximum.
For companies, the collective bargaining window between May and December 2026 is strategic. Early legal advice can make the difference between an orderly transition and a costly collective dispute.
✒️ Anticipate the labor disputes that the reform may bring. Baráibar & Asociados has the experience in Labor Law to protect your company's contracts in Mexico City before the effective reduction of working hours begins in 2027.
Conclusion: The reform is now in effect. Your company must act now.
The reduction of the workweek from 48 to 40 hours is the most significant legal change for Mexican companies in the last decade. The decree has already been published. The law has already changed. What is being implemented gradually is the cap on working hours, but the preparation requirements are immediate.
Companies that take action before December 31, 2026, will have updated contracts, implemented record-keeping systems, and streamlined payroll processes. Those that wait will face fines, lawsuits, and the cost of a chaotic transition under pressure.
The time to act is now.
Frequently Asked Questions about the 40-Hour Labor Reform in Mexico
From when does the reduced working hours effectively apply? The effective reduction in working hours begins on January 1, 2027, with a limit of 46 hours per week. The period from May 1 to December 31, 2026, is an adaptation phase, as stipulated in the decree published in the Official Gazette of the Federation (DOF) on May 1, 2026 (Federal Labor Law, first transitional article).
Can the employer reduce the salary because fewer hours are now being worked? No. The decree expressly amends Articles 59 and 61 of the Federal Labor Law to prohibit any reduction in wages, salaries, or benefits resulting from a reduction in working hours. Doing so constitutes a serious violation of workers' labor rights.
What happens if my company does not implement electronic attendance registration? As of January 1, 2027, the lack of electronic registration is sanctioned with fines of between 250 and 5,000 UMA per infraction, equivalent to between $29,327 and $586,550 pesos in 2026, according to the new article 994, section IV Bis, of the LFT.
Are the current contracts still valid or do they need to be modified? Contracts stipulating workdays exceeding the new legal limit must be modified before December 31, 2026. Failure to do so creates legal risk, as clauses that contravene the Federal Labor Law are null and void, according to Article 33 of the Federal Labor Law.
Are overtime hours still paid the same as before? Not entirely. With the reform, all overtime hours will be paid at double the regular rate, without exception. The weekly overtime limit will be gradually adjusted until it reaches 12 hours by 2030, as stipulated in the amended Article 68 of the Federal Labor Law.
Does the reform also apply to domestic workers and agricultural workers? The Federal Labor Law (LFT) establishes special regulations for domestic and agricultural workers. However, the general principle of reduced working hours and the prohibition of wage reductions applies to all employment relationships. For specific sectors, it is advisable to review each case individually with a specialist.
Legal References
- Decree reforming sections IV and XI of Part A of Article 123 of the Political Constitution of the United Mexican States, regarding the reduction of the working day (DOF 03/03/2026). https://sidof.segob.gob.mx/notas/docFuente/5781417
- Decree reforming, adding to, and repealing various provisions of the Federal Labor Law regarding the reduction of working hours (DOF 01/05/2026). https://sidof.segob.gob.mx/notas/docFuente/5786537
- Parliamentary Gazette (Chamber of Deputies), initiative related to rest periods (2 days for every 5 worked) (14/04/2026). https://gaceta.diputados.gob.mx/Gaceta/66/2026/abr/20260414-II-4.html
This article is for informational purposes only and does not constitute formal legal advice or establish an attorney-client relationship.
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