For accountants · 3 min read

The 8 questions your clients will ask about the time clock

Short answer

These are the questions that come up most often, with a short answer to each.

Questions and answers

Do I have to buy a time clock? No. The law requires an electronic record.
Do I need a fingerprint? No.
How much is the fine? From 250 to 5,000 UMA.
Does it apply to me if I am small? The law makes no distinction; the STPS still has to define exceptions.
Since when? The STPS rules take effect on January 1, 2027.
Does my notebook work? No.
Is there a certified system? That certification does not exist.
How much does compliance cost? Sicheca starts at $149 MXN per month.

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.

Weekly limits by year
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

Calculating payroll with the hours the client remembers.
Averaging overtime across weeks.
Not warning the client when the record and the payslip do not match.
Treating the record as a topic for the lawyer only.
Waiting for the client to ask.

What to do now

List your clients who have employees.
Ask each one how they record working time.
Send them a summary of the reform.
Review their overtime from the last month against the new caps.
Recommend an electronic record to them and ask for view access.

Related terms

What is NOM-035. NOM-035 is the STPS standard that requires identifying and preventing psychosocial risk factors at work, such as excessive workloads and long workdays.

What is the contribution base salary (SBC). The contribution base salary is the salary used to calculate IMSS contributions and INFONAVIT contributions.

Overtime: what it is. Overtime is the hours worked above the ordinary workday.

Frequently asked questions

Where is everything explained?

In the reform guide on the Sicheca site.

Does salary go down if fewer hours are worked?

No. The reform prohibits lowering wages and benefits because of the reduction in working hours.

Is the reform already in force?

Yes. The reform to the Federal Labor Law took effect on May 1, 2026. The reduction in working hours starts on January 1, 2027.

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.

Legal basis and sources

Electronic working-time record: article 132, section XXXIV, of the LFT and fifth transitory provision of the decree.
Decree amending the Federal Labor Law on the reduction of the working week. Official Gazette of the Federation, May 1, 2026.
Federal Labor Law, current text. 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.