Business
Mexico — Business: Social Security
Mexican employers must register with three bodies before any employee starts work: SAT (tax), IMSS (social security), and INFONAVIT (housing fund). IMSS registration is mandatory pre-employment and covers health/maternity insurance, disability and life insurance, retirement/old-age savings, and childcare services — the employer bears the overwhelming majority of the contribution burden (~20-35%+ of SBC) and is operationally responsible for enrollment and monthly payments. INFONAVIT requires an additional 5% of base salary, mandatory for all registered employees, funding employee access to housing loans and interest subsidies. Failure to register on time triggers fines, surcharges, and retroactive contribution assessments. Combined with SAR (retirement) and state payroll tax, total mandatory employer contributions add 30-40% on top of base salary.
Key facts
- Three mandatory registrations before hiring: SAT (tax), IMSS (social security), INFONAVIT (housing fund).
- IMSS registration must occur before an employee's start date — no grace period.
- INFONAVIT: additional mandatory 5% of base salary for all registered employees.
- Late registration triggers fines, surcharges, and retroactive contribution assessments.
Steps
- Register with SAT — Tax registration for the employer entity.
- Register with IMSS — Mandatory before the employee's start date.
- Register with INFONAVIT — Housing fund, 5% of base salary.
Costs
- INFONAVIT employer contribution: 5% of base salary
Common mistakes
- Registering with IMSS after an employee has already started work — registration is required before the start date, and late registration triggers fines and retroactive assessments.