On March 3, 2026, President Claudia Sheinbaum signed into law a constitutional amendment reducing Mexico's maximum workweek from 48 to 40 hours — the most significant change to the country's labor framework since 1931. The Federal Labor Law amendment followed on May 1, 2026, translating the constitutional change into specific employer obligations that take effect beginning January 1, 2027.
Most coverage of this reform has focused on what it means for workers: more rest time, stronger overtime protections, a better work-life balance. That framing is accurate, but it leaves a significant question unanswered for the employers responsible for implementation.
What does this reform actually require of a company managing 200 workers across 12 construction sites? A facility management firm covering 80 client buildings on rotating shifts? A logistics operation running three-shift depots with a mix of direct employees and contractors?
This article is written for those operators. It covers what changes each year from 2027 to 2030, the electronic work-hour recording obligation that takes effect January 1, 2027, why companies managing multi-site and shift-based workforces carry a more complex compliance burden than most reform coverage acknowledges, and what the May–December 2026 preparation period should look like in practice.
What Mexico's Workweek Reform Actually Changes
On March 3, 2026, the decree amending Article 123, Section A of Mexico's Political Constitution was published in the Official Gazette of the Federation (DOF), formally completing the constitutional reform process. The Federal Labor Law (FLL) amendment followed on May 1, 2026, establishing the specific employer obligations that govern implementation. The remainder of 2026, from May 1 through December 31, is designated as a preparation period for employers to assess and adjust operations before the first hour reduction takes effect.
The phased reduction schedule
The workweek reduction does not begin immediately. The current maximum of 48 hours remains in effect through December 31, 2026. Starting January 1, 2027, the maximum decreases by two hours each year until reaching 40 hours in 2030.
No sector-specific exceptions apply to this reduction schedule. Every employer subject to the FLL operates on the same timeline, regardless of industry.
For operations teams, this schedule has a practical implication that is easy to underestimate: compliance is not a one-time adjustment. Rosters, shift structures, payroll models, and overtime policies will need to be reviewed and updated before each January 1 reduction, four times between now and 2030.
Overtime restructuring
The FLL amendment also restructures the overtime framework, with the permitted overtime cap increasing gradually as the ordinary workweek decreases. By 2030, employers may schedule up to 12 overtime hours per week, distributed across no more than four hours per day on a maximum of four days per week. Total daily working time, ordinary hours plus overtime, may never exceed 12 hours.
Overtime compensation follows a two-tier structure. The first 12 overtime hours worked in a week must be paid at a 100% premium above the employee's regular wage. Hours beyond that threshold must be compensated at a 200% premium. Workers under 18 are explicitly prohibited from working overtime under the amended law.
The overtime cap increases per year are as follows:
Note: Holland & Knight notes this overtime transition framework was presented as part of the Federal Executive's operational transition plan and is expected to be defined in detail through FLL secondary legislation.
What does not change
Three protections from existing law are preserved and explicitly restated in the amendment. Workers retain the right to at least one full paid rest day for every six days worked. A six-day schedule remains permissible where employer and employee agree to it. The reform does not mandate a five-day workweek. And wages, salaries, and benefits cannot be reduced as a consequence of the workweek reduction. This prohibition is express and non-negotiable under the constitutional text.
The Compliance Obligation Most Employers Are Underestimating
The phased hour reduction is the part of the reform that has received the most attention. It is not, however, the obligation that creates the most immediate operational pressure for employers.
The FLL amendment, in force since May 1, 2026, introduces a mandatory electronic work-hour recording obligation. Under this requirement, employers must maintain electronic records of each employee's working hours, including start and end times. This obligation takes effect January 1, 2027. The STPS will issue guidelines defining the scope of application and any implementation criteria before that date. Those guidelines had not been published as of this writing.
The statutory deadline is fixed. The implementation details are still being defined. Employers should treat the current period as active preparation, not a waiting period.
What the electronic record means as evidence
The practical significance of this obligation extends beyond administration. Under the FLL amendment, compliant electronic time records may carry substantial evidentiary weight in labor disputes and regulatory proceedings. Littler notes that the content of an electronic record constitutes conclusive evidence where it can be demonstrated that it was agreed upon by employer and employee.
An employer relying primarily on manual records may face a materially weaker evidentiary position in disputes involving hours worked, overtime, or schedule adherence. In a dispute over hours worked, overtime owed, or schedule adherence, “the absence of compliant electronic records may significantly weaken the employer’s position during inspections or labor disputes. The reform does not eliminate the possibility of labor disputes. It changes what evidence is required to resolve them.
Fine structure
Non-compliance with the electronic recording obligation carries fines of 250 to 5,000 UMAs, equivalent to MXN $29,327.50 to $586,550.00 (approximately USD $1,675 to $33,517). These figures are drawn from Ogletree Deakins' analysis of the FLL amendment's UMA-based penalty scale.
For context, a mid-size employer found non-compliant across a workforce of several hundred employees is not facing a single fine. STPS inspection findings can be applied per violation, per employee, or per inspection cycle depending on how the regulatory guidelines are structured. The precise enforcement mechanism will be clarified in forthcoming STPS guidelines.
Heightened legal exposure for sustained overtime violations
The reform establishes a link between the electronic recording obligation and labor exploitation statutes. Ogletree Deakins notes that sustained overtime non-compliance, combined with increased STPS inspection authority, could escalate beyond a labor dispute into a criminal matter. This assessment remains subject to forthcoming STPS regulatory guidance and should not be read as a definitive legal prediction. It is included here because it reflects the direction of the regulatory framework, not to overstate the risk for employers acting in good faith.
For the majority of employers, the primary compliance risk is operational and financial. The fine exposure is real. The evidentiary gap created by manual attendance systems is real. Those are the two areas that warrant immediate attention.
What Electronic Work-Hour Recording Looks Like in Practice
Understanding what the FLL amendment requires is one thing. Translating that into an operational system across a multi-site workforce is another. This section covers what compliant electronic recording means in practice, and what to look for when evaluating whether a system meets the standard the reform establishes.
What the FLL amendment requires operationally
Operationally, employers should expect compliant electronic recording systems to support four core capabilities:
Individual-level records. The obligation is per employee, not per team or per site. A system that records aggregate shift coverage without attributing specific start and end times to each individual worker may not fully satisfy the expected compliance standard.
Start and end timestamps. The reform specifically requires recording of start and end times, not just total hours worked. A system that calculates daily hours without capturing the timestamps at the moment of clock-in and clock-out does not produce the record the amendment requires.
Accessibility on demand. STPS inspectors may request records during a site visit. Labor proceedings may require records to be produced quickly and in verifiable form. Records that exist only in a local spreadsheet, a supervisor's notebook, or a system that requires manual export and consolidation before they can be presented create operational risk at precisely the moment when speed and accuracy matter most.
Employer-employee agreement. Littler notes that electronic records carry conclusive evidentiary weight where it can be demonstrated they reflect terms agreed upon by both parties. For employers implementing a new system, documenting that workers have been informed of and agreed to the recording method is part of building a defensible record.
What this means for multi-site employers specifically
A compliant system for a multi-site workforce needs to do more than record attendance at a single location. Records must be consolidated across all sites in real time, accessible remotely without manual aggregation, and attributable to individual workers regardless of which site they are working at on a given day.
For industries where workers rotate between sites, are deployed on short-cycle projects, or work under contractor arrangements, the system also needs to function without fixed hardware at every location. A solution that requires installing a physical terminal at each site is impractical for a construction firm where sites open and close with project timelines, or a facility management company that adds and loses client buildings throughout the year.
What A Compliant Multi-Site Attendance System Needs To Do
For employers operating across multiple sites, compliance is ultimately an infrastructure problem rather than a payroll problem. The practical requirement is not simply digitizing attendance, but creating a system capable of producing individually attributable, timestamped, location-verifiable work-hour records across every active site in real time.
In practice, that means a compliant system needs to support:
- individual employee-level clock-ins and clock-outs
- real-time timestamping at the moment of occurrence
- centralized visibility across distributed sites
- remote retrieval during inspections
- audit-traceable records
- location verification for field-based workforces
- deployment without fixed hardware at every site
This becomes particularly important in industries such as construction, facility management, logistics, manufacturing, and security, where workers frequently rotate across locations, projects, and shifts.
How Truein Fits This Operational Requirement
Truein is designed for multi-site and contractor-heavy workforces where attendance compliance must function across distributed field operations rather than a single centralized workplace.
Workers can clock in and out using face recognition on smartphones or shared devices, while GPS geofencing verifies the worksite location at the time the record is created. Because the system does not rely on fixed biometric terminals at every site, employers can deploy attendance tracking across temporary projects, rotating sites, and contractor-managed locations without additional hardware installation.
Attendance records are stored electronically with timestamp history and centralized visibility across all sites, allowing operations and HR teams to retrieve records remotely when required during audits, inspections, payroll reviews, or labor disputes.
Truein currently supports workforce operations across 10,000+ locations globally, including companies operating large multi-site workforces in construction, manufacturing, facility management, logistics, and security. Schedule a demo to check how Truein can solve your operational challenges.
Why Multi-Site and Shift-Based Workforces Face a More Complex Burden
The FLL amendment applies uniformly. There are no industry carve-outs for the phased hour reduction, and the electronic recording obligation covers all employers subject to the FLL. For a single-location employer with centralized HR and a fixed shift structure, implementing electronic time tracking is largely a procurement and onboarding decision.
For companies managing workers across multiple sites, that same obligation is an infrastructure decision of a different order.
The field operations problem
Consider what electronic work-hour recording actually requires in a multi-site context. Every worker, at every location, needs a compliant method of recording start and end times individually and in real time. In a construction company operating 15 active job sites, a facility management firm covering 80 client buildings, or a logistics operation running three-shift depots across multiple cities, there is no central HR desk at each location. There is no supervisor whose primary role is attendance verification. Sites open and close with project cycles. Workforce composition changes week to week as contractor crews rotate in and out, making contract worker attendance management one of the most operationally complex aspects of reform compliance for multi-site employers.
The compliance infrastructure that a single-office employer installs once needs to follow the workforce wherever it goes.
Rotating shifts and contractor complexity
Shift-based industries face a layered version of this problem. A manufacturing plant running three shifts needs to track, cap, and record hours per employee across each shift, not just total weekly hours. A security company covering 24-hour posts needs to demonstrate that no individual worker exceeded the weekly hour cap, even when coverage requirements create pressure to extend shifts. A construction firm using subcontracted labor needs clarity on where the recording obligation sits when workers are not direct employees — and whether the time tracking software for construction they currently use produces records that meet the new evidentiary standard.
These are not edge cases. They are standard operating conditions in the industries most directly affected by the reform: construction, facility management, manufacturing, logistics, and security.
The inspection reality
STPS inspectors do not only visit head offices. Labor inspections occur at the worksite. When an inspector arrives at a job site or a client building, the question of compliance becomes immediate and local. Can the employer produce individual time records for workers present at that location? Are those records accessible remotely in real time, or does retrieval require a call to a central office?
Holland & Knight notes that increased labor inspections and oversight related to controlling working hours are expected as a direct consequence of the reform. For multi-site employers, that expectation has a specific operational implication: compliance cannot live only at headquarters. It needs to be verifiable at every location, on demand.
The companies that will find January 2027 most manageable are those that have already solved the problem of recording attendance accurately across every site in their network, not just at the locations where HR happens to be present.
Why Manual Attendance Systems Are Inadequate Under the New Standard
The electronic recording obligation does not simply add a new administrative task to an existing process. It establishes a specific evidentiary standard that manual attendance systems cannot meet.
This distinction matters most not during day-to-day operations, but at the two moments when attendance records carry legal weight: an STPS inspection and a labor dispute.
The evidentiary problem with spreadsheets
A spreadsheet has no verifiable timestamp. An entry recording that a worker clocked in at 7:00 AM and out at 5:00 PM on a given date cannot demonstrate when that entry was made, whether it was edited after the fact, or whether it reflects what actually occurred. In an STPS inspection or a labor proceeding, a spreadsheet is a document. It may not satisfy the evidentiary standard contemplated under the amended framework.
The evidentiary problem with paper registers
A paper attendance register records presence, not time. A signature on a sheet confirms that a worker was present on a given day. It does not establish start time, end time, total hours worked, or whether the weekly hour cap was observed. It also cannot be consolidated across multiple sites without manual transcription, a process that introduces gaps, delays, and editing risk before the record is ever presented to an inspector or a court.
The evidentiary problem with supervisor-reported hours
When a supervisor records hours on behalf of a team, the record has no independent audit trail. What was entered and what occurred are unverifiable by any third party. In a dispute where a worker claims longer hours than the supervisor recorded, the employer has no corroborating evidence. The record itself becomes a dispute.
What the reform requires instead
Littler notes that electronic records constitute conclusive evidence under the reform where they can be shown to have been agreed upon by employer and employee. The direction of the reform points toward electronically verifiable, individually attributable, timestamped records that can be retrieved and reviewed when required during inspections or disputes.
The question for any employer reviewing their current attendance process is not whether they track hours in some form. Most do. The question is whether their current method produces records that meet that standard. For most companies still relying on manual systems, the honest answer is no.
Conclusion
Mexico's 40-hour workweek reform is structured as a gradual transition. The hour reductions phase in over four years. The STPS will issue implementation guidelines before the electronic recording deadline. The law gives employers a preparation period running through December 31, 2026.
None of that makes the current period a waiting period.
The FLL amendment is in force. The electronic work-hour recording obligation has a statutory deadline of January 1, 2027. For companies managing workers across multiple sites and shifts, the work between now and that date is not administrative. It is operational: identifying the right system, piloting it across representative sites, onboarding workers, configuring location policies, and verifying that the records produced meet the evidentiary standard the reform establishes before inspections begin.
The reform also repeats every January 1 through 2030. Each year brings a new maximum hour threshold, a revised overtime cap, and the same underlying requirement: individual, timestamped, tamper-proof records for every worker at every site. Companies that build compliant attendance infrastructure now are not just solving for 2027. They are building the foundation that each subsequent reduction cycle will depend on.
The businesses best positioned for this transition are the ones treating the second half of 2026 as an active preparation window, not a holding pattern. The fine exposure is real. The evidentiary gap created by manual systems is real. And for multi-site employers in construction, facility management, manufacturing, logistics, and security, the operational complexity of getting this right across every location is significant enough that the time to start is not December.
See how Truein helps multi-site employers in Mexico prepare for the electronic work-hour recording obligation with tamper-proof, GPS-verified attendance records across every site. Book a demo.
Frequently Asked Questions
When does Mexico's 40-hour workweek take effect?
The constitutional amendment was published in the Official Gazette of the Federation on March 3, 2026. The Federal Labor Law amendment entered force on May 1, 2026. The hour reduction itself begins January 1, 2027, when the maximum workweek drops from 48 to 46 hours. It then decreases by two hours each year, reaching 40 hours on January 1, 2030. The current maximum of 48 hours remains in effect through December 31, 2026.
Will Mexico require electronic time tracking for employers?
Yes. The FLL amendment, in force since May 1, 2026, requires employers to maintain electronic records of each employee's working hours, including start and end times. This obligation takes effect January 1, 2027. The STPS will issue guidelines defining the scope of application and any implementation criteria before that date. Those guidelines had not been published as of this writing. Employers should treat the current period as active preparation rather than a waiting period.
What are the fines for non-compliance with Mexico's attendance tracking rules?
Non-compliance with the electronic work-hour recording obligation carries fines of 250 to 5,000 UMAs, equivalent to MXN $29,327.50 to $586,550.00 (approximately USD $1,675 to $33,517). These figures reflect Ogletree Deakins' analysis of the FLL amendment's UMA-based penalty scale. The precise enforcement mechanism per violation, per employee, or per inspection cycle will be clarified in forthcoming STPS guidelines.
Are there sector-specific exceptions to the 40-hour workweek reform?
No sector-specific exceptions apply to the phased hour reduction schedule. Every employer subject to the FLL operates on the same timeline regardless of industry. The electronic recording obligation is subject to implementation criteria and any exemptions to be defined by the STPS in forthcoming guidelines. Until those guidelines are published, employers across all sectors should assume the obligation applies to them.
Does the reform apply to construction and contractor workforces?
Yes. The FLL amendment applies across all sectors with no industry carve-outs for the hour reduction schedule. Construction, facility management, manufacturing, logistics, and security companies are all subject to the same phased reduction timeline and electronic recording obligation. For industries managing contractor crews and rotating workforces across multiple sites, the operational challenge of building compliant attendance infrastructure is more complex than for single-location employers, but the legal obligation is the same.
Can employers still use a six-day schedule under the new law?
Yes. The reform preserves the right of employers and employees to schedule weekly hours across six days by mutual agreement. The reform does not mandate a five-day workweek. Workers retain the right to at least one full paid rest day for every six days worked, as under existing law.
What happens if an employer cannot produce time records during an STPS inspection?
The FLL amendment establishes electronic records as the primary evidentiary standard for working hours. Littler notes that compliant electronic records constitute conclusive evidence in disputes where they can be shown to reflect terms agreed upon by employer and employee. An employer without compliant records has no equivalent evidentiary substitute. In a labor dispute or STPS inspection, the absence of compliant records weakens the employer's position by default. The reform does not create new categories of liability for this scenario specifically, but the evidentiary gap it creates is a material operational risk for employers relying on manual systems.
What does "electronic time tracking" mean under the Federal Labor Law amendment?
The FLL amendment requires employers to electronically record the working hours of each employee, including start and end times. Baker McKenzie describes this as an obligation to implement an electronic time-recording system, the scope and exceptions of which will be defined by the STPS. Mexico Business News notes that the statutory text requires employers to electronically record the working day of each employee, including start and end times, and provide this information to authorities when required. A system that meets this standard produces individual, timestamped records at the moment of clock-in and clock-out, consolidated and accessible on demand.
