Employee Files in Mexico: Legal Requirements, Structure, and Best Practices for 2026

The employee file is the documentary foundation of the relationship between employer and worker in Mexico. Beyond being a simple repository of papers, it constitutes the legal evidence supporting compliance with employer obligations before the Secretaría del Trabajo y Previsión Social (STPS), the Instituto Mexicano del Seguro Social (IMSS), the SAT, and the labor courts (Juntas de Conciliación y Arbitraje). Despite its importance, many Mexican companies still maintain incomplete, disorganized, or expired files, exposing them to financial penalties, labor contingencies, and unfavorable rulings.

In this guide, we detail the current legal requirements, recommended structure, most frequent errors, and best practices for managing employee files in Mexico during 2026.

Legal basis for the employee file in Mexico

The obligation to compile and retain employee files does not stem from a single article but from a set of legal provisions that, taken together, define which documents the employer must safeguard and for how long.

Ley Federal del Trabajo (LFT)

Article 804 of the LFT expressly establishes the documents that the employer is required to retain and present in the event of a labor lawsuit. This article is the cornerstone of the employee file because it reverses the burden of proof: if the employer cannot produce the required documents, the facts alleged by the employee are presumed to be true.

The documents that Article 804 requires to be retained include:

• Individual employment contracts entered into, when no collective bargaining agreement or industry-wide contract is applicable.
• Payroll records or lists of personnel, when used.
• Salary payment receipts.
• Proof of profit-sharing payments (PTU), vacation pay, year-end bonuses (aguinaldo), and other benefits referred to in the LFT.
• Attendance records when maintained at the workplace.
• Proof of INFONAVIT contributions and contributions to the retirement savings system (SAR).

Article 805 complements the preceding one by establishing that the employer who fails to present these documents will be presumed to have confirmed the facts alleged by the employee in their complaint, unless proven otherwise. This makes the employee file an indispensable legal shield.

Ley del Seguro Social and IMSS regulations

The Ley del Seguro Social requires the employer to retain documentation related to employee registrations, terminations, and salary modifications filed with the IMSS. Enrollment notices, records of changes, and disability certificates should form part of the file. In the event of an audit, the IMSS may request this documentation to verify that employer-employee contributions have been correctly calculated.

Código Fiscal de la Federación and SAT obligations

From a tax perspective, the employer must retain payroll Comprobantes Fiscales Digitales por Internet (CFDI), employee constancias de situación fiscal, and documentation supporting applied deductions. Article 30 of the Código Fiscal de la Federación establishes a five-year retention period from the date on which the related tax returns were or should have been filed.

NOM-151 and electronic document conservation

NOM-151-SCFI-2016 regulates the requirements for conserving electronic data messages and digitizing documents. For companies managing their files in electronic format, compliance with this standard is fundamental, as it defines the conditions under which a digital document has the same evidentiary value as its paper equivalent. The conservation certificate issued by an authorized Certification Services Provider (PSC) is the mechanism that guarantees the integrity and authenticity of the document over time.

Required documents: the complete list

Beyond the documents expressly required by the LFT, legal practice and operational needs have consolidated a broader set of documents that every employee file should contain. They are detailed below, grouped by function.

Identification and personal data documents

• CURP (Clave Única de Registro de Población): an essential document for registration with the IMSS and INFONAVIT. It must be verified to match the employee's data.
• RFC (Registro Federal de Contribuyentes): required for payroll CFDI stamping. The employee's RFC must be active and free of inconsistencies.
• Constancia de situación fiscal (CSF): issued by the SAT, it confirms the employee's tax regime and fiscal domicile. Following recent reforms, the CSF must be current and the regime must correspond to the type of employment relationship.
• Número de Seguridad Social (NSS): assigned by the IMSS, essential for registering the employee with the Institute.
• Recent proof of address: generally no more than three months old. This may be a utility bill (electricity, water, telephone) or bank statement.
• Copy of valid official identification: INE/IFE voter credential or passport.
• Birth certificate.
• Proof of education: professional degree, professional license, or certificate, as required by the position.

Contractual and employment relationship documents

• Individual employment contract signed by both parties, specifying position, salary, working hours, workplace, and start date.
• Amendment agreements for changes in position, salary, schedule, or conditions.
• Payroll receipts (stamped CFDI): must be retained systematically, period by period.
• Signed acknowledgments of receipt for the internal regulations, code of ethics, privacy policy, and other internal policies.
• Training certificates (DC-3): mandatory under Article 153-A of the LFT.
• Attendance records and time-tracking logs.
• Administrative incident reports for absences or breaches.
• Performance evaluations.

Termination documents

• Voluntary resignation letter or termination notice.
• Termination agreement ratified before the competent authority.
• Detailed and signed final settlement or severance package.
• IMSS de-registration notice.
• Employment certificate issued to the employee.

Recommended structure for the employee file

A well-structured employee file not only facilitates regulatory compliance but also streamlines internal processes such as audits, promotions, transfers, and terminations. The ideal structure organizes documents into thematic sections that follow the employee's lifecycle within the organization.

Section 1: Onboarding documents and personal data

This section contains all information collected at the time of hiring:

• Duly signed employment application.
• Resume and documentation supporting prior work experience.
• Copy of valid official identification (INE, passport).
• Birth certificate.
• CURP.
• Constancia de situación fiscal (RFC with updated data from the SAT).
• Número de Seguridad Social (NSS) from the IMSS.
• Recent proof of address.
• Proof of education (degree, professional license, or certificate as required by the position).
• Criminal background check (when required by the position).
• Verified employment references.
• Recent photograph.

Section 2: Contractual documents

The legal core of the file, where the formal agreements between the parties are concentrated:

• Individual employment contract signed by both parties, with start date, position, salary, working hours, and specific conditions.
• Amendment agreements for changes in position, salary, schedule, or working conditions.
• IMSS registration notice.
• INFONAVIT enrollment notice.
• Confidentiality agreements or non-compete clauses, when applicable.
• Signed acknowledgments of internal policies (internal regulations, code of ethics, personal data protection policy).

Section 3: Payroll and compensation documents

The historical record of the employee's earnings and deductions:

• Payroll receipts (stamped payroll CFDI).
• Proof of year-end bonus (aguinaldo) payment.
• Vacation and vacation premium receipts.
• PTU receipts (Profit Sharing).
• Records of bonuses, commissions, or variable compensation.
• Proof of meal vouchers, savings fund, or other benefits.

Section 4: Active employment relationship documents

Documents generated during the employee's tenure:

• Attendance records and time-tracking logs.
• Vacation requests and approvals.
• Disability certificates issued by the IMSS.
• Administrative incident reports for absences, tardiness, or breaches.
• Performance evaluations.
• Training certificates received (compliance with Article 153-A of the LFT).
• Salary modification notices filed with the IMSS.
• Workplace accident or occupational illness documentation.

Section 5: Termination documents

The section added upon conclusion of the employment relationship:

• Voluntary resignation letter or termination notice, as applicable.
• Employment termination agreement ratified before the competent authority.
• Detailed and signed final settlement or severance package.
• IMSS de-registration notice.
• Employment certificate or recommendation letter issued.
• Company assets and equipment return receipt.

Legal retention periods

One of the most critical and frequently misunderstood aspects of the employee file is how long documentation must be retained. Retention periods vary depending on the authority and the type of document:

• General labor documents (LFT): must be retained throughout the employment relationship and for at least one year after its termination, in line with the statute of limitations for labor actions.
• Tax documentation (payroll CFDI, tax certificates): five years from the filing of the corresponding tax return, under Article 30 of the Código Fiscal.
• IMSS documentation: five years for purposes of the Institute's tax credit statute of limitations.
• Employment contracts and payroll receipts in litigation: if a lawsuit is pending, the file must be retained until the final resolution of the matter, regardless of the general deadlines.

The practical recommendation is to retain complete employee files for a minimum of five years after termination of the employment relationship, simultaneously covering tax, social security, and labor obligations.

Digitization of the employee file

Managing employee files on paper presents limitations that are increasingly difficult to justify compared to digital alternatives. NOM-151 provides the legal framework that allows documents to be retained in electronic format with the same validity as paper, provided the requirements for integrity, accessibility, and a conservation certificate issued by an authorized PSC are met.

The digitization process involves several key elements:

• Evidentiary-quality scanning: physical documents must be digitized at a minimum resolution of 200 DPI, in PDF/A format for long-term preservation, verifying legibility and completeness.
• NOM-151 conservation certificate: each digitized document must have a certificate issued by a PSC authorized by the Secretaría de Economía, certifying integrity and conservation date.
• Electronic signature: new documents can be electronically signed from day one, eliminating the cycle of printing, manual signing, and subsequent scanning.
• Complete audit trail: the system must record who accessed each document, when it was viewed, whether it was downloaded or modified, generating an immutable audit trail.

Platforms like Rokisoft automate this entire cycle: from document collection during onboarding, through the employee's electronic signature, to the automatic generation of NOM-151 certificates and encrypted, backed-up storage. Companies like Ford, Oracle, and Bachoco manage hundreds of thousands of labor documents per year this way, without manual processes.

Common errors in employee file management

Drawing on years of experience in labor compliance in Mexico, these are the errors that occur most frequently in organizations of all sizes:

1. Unsigned contracts or contracts with incomplete data

It is surprisingly common to find employment contracts that were never signed by the employee, that lack the employment start date, or that do not clearly specify the integrated salary. In a labor lawsuit, an incomplete contract can be as detrimental as having no contract at all.

2. Missing amendment agreements

When an employee receives a raise, changes position, or modifies their schedule, these conditions must be documented through an amendment agreement appended to the original contract. Omitting these documents creates discrepancies between the formal terms and the actual employment relationship.

3. Unstamped payroll receipts

Following recent tax reforms, every payroll payment must be supported by a CFDI duly stamped with the SAT. Companies that issue informal receipts or that have systematic errors in stamping not only face tax risks but also weaken their evidentiary position in labor disputes.

4. Outdated constancias de situación fiscal

The employee's constancia de situación fiscal (CSF) must be current and accurately reflect their tax regime and domicile. Using expired or incorrect certificates generates errors in payroll stamping that can lead to SAT notices and demands.

5. Lack of training evidence

Article 153-A of the LFT requires employers to provide training to their workers. However, many companies fail to document training activities, leaving them without evidence of compliance during STPS inspections. DC-3 certificates must form part of the file.

6. Files fragmented across departments

It is common for Human Resources to hold one portion of the file, the Payroll department another, the Legal department another, and Occupational Health and Safety yet another. This fragmentation hinders a comprehensive view of the file and creates documentary gaps that are only discovered when it is too late.

Relevant regulatory changes for 2026

The labor regulatory environment in Mexico continues to evolve. Among the most significant changes impacting file management during 2026 are:

• Increased SAT scrutiny of payroll CFDI: the tax authority has intensified automated electronic reviews to detect discrepancies between issued CFDIs and filed returns. Keeping payroll receipts properly integrated into the file is more important than ever.
• Outsourcing reforms and their documentary impact: companies using specialized services must accurately document service contracts, the contractor's tax and labor compliance certificates, and current REPSE registrations.
• STPS inspections focused on working conditions: inspections are placing greater emphasis on documentation of working hours, workplace violence prevention protocols, and training programs — all elements that must be supported in the file.
• Personal data protection: employee file management must comply with the Ley Federal de Protección de Datos Personales en Posesión de los Particulares (LFPDPPP), which requires signed privacy notices and security measures for safeguarding sensitive employee information.

Best practices for file management in 2026

To conclude, these are the practices we recommend for any organization seeking to keep its employee files in optimal condition:

1. Define an internal file policy: formally document which documents must be included in each file, who is responsible for collecting them, within what timeframe, and in what format.
2. Centralize management on a single platform: avoid dispersing documents across departments, email, and shared folders. A single repository ensures consistency.
3. Automate expiration alerts: configure notifications for documents with expiration dates, such as constancias de situación fiscal, licenses, certifications, and fixed-term contracts.
4. Conduct periodic internal audits: review a representative sample of files quarterly to detect missing documents before an authority requests them.
5. Train HR staff: the team responsible for assembling files must understand the legal foundations and the consequences of an incomplete file.
6. Implement electronic signatures from day one: capture the employee's signature on the contract, internal policies, and payroll receipts from the first day, eliminating the accumulation of unsigned documents.
7. Separate active from historical documents: maintain a clear process for archiving former employees' files, respecting legal retention periods without cluttering the active repository.
8. Comply with personal data protection: restrict file access solely to authorized personnel and maintain evidence of the privacy notice signed by each employee.

Conclusion

The employee file in Mexico is not just another bureaucratic formality: it is the employer's first line of legal defense and the tangible evidence of a responsibly managed employment relationship. In an environment where STPS inspections are more frequent, the SAT cross-references information automatically, and labor lawsuits are decided based on the documentation presented, maintaining complete, organized, and accessible files is no longer an option but an operational necessity.

Companies that adopt specialized document management tools like Rokisoft not only reduce their legal risks but also gain efficiency, visibility, and peace of mind. The investment in a robust employee file process pays for itself the first time it prevents a contingency.