Employer Social Security Contributions in Mexico:
Complete 2026 Breakdown

If you're modeling the cost of a Mexican hire, the salary you see in an offer letter is not what you'll pay. Mexican employers carry a mandatory social security burden on top of base pay, split across seven separate contribution categories. None of them are optional, and none of them are negotiable.

This is the number CFOs ask for first when they're comparing a Mexican-entity payroll provider against a US/Canada payroll run: what's the real all-in cost per employee. Here's the line-by-line answer.

What employers pay vs. what employees pay

Mexican social security splits contributions between employer (patrón) and employee (trabajador), similar in structure to US FICA but with more categories and no employee opt-out. The employer's share is larger across every category, and three of the seven don't have an employee-side contribution at all: Retiro, Guarderías y Prestaciones Sociales, and INFONAVIT are employer-only.

That asymmetry is the first thing a US or Canadian HR director notices when they see a Mexican payroll breakdown for the first time. It's not a rounding difference, it's a structural one.

The IMSS contribution categories

IMSS (Instituto Mexicano del Seguro Social) runs five insurance branches, and the employer pays into all of them. Here's what each one costs on the employer side, as of 2026:

That last one, Cesantía en Edad Avanzada y Vejez, catches people off guard because it's not flat. It scales with how many UMAs (Unidad de Medida y Actualización, Mexico's inflation-indexed reference unit) the employee earns, from 3.150% at the lowest tier up to 7.51% once the salary passes 4.01 UMA. A higher earner costs proportionally more in this one category alone.

INFONAVIT: the housing fund

Separate from IMSS, every employer pays 5.00% of the employee's salary base into INFONAVIT (Instituto del Fondo Nacional de la Vivienda para los Trabajadores). This funds a national housing credit system employees can draw on for a mortgage. It's employer-only, flat, and non-negotiable. No US or Canadian equivalent exists as a mandatory payroll line item, which is usually the second thing that surprises a foreign HR team.

State payroll tax (ISN) on top of federal contributions

Everything above is federal. On top of it, each of Mexico's 32 states charges its own Impuesto Sobre Nómina (State Payroll Tax, ISN), typically 1% to 4% of payroll, with its own rules for what counts as taxable. If you have employees in more than one state, you're filing ISN separately in each one, at each state's rate.

What this adds up to

Stack all of it, IMSS, INFONAVIT, and ISN, and the typical total employer burden lands between 30% and 35% of base salary for a mid-range earner, before the state tax gets added on top. The exact number moves with the employee's salary level (because of the CEAV tier) and the company's occupational risk class (because Riesgos de Trabajo isn't flat).

There's a hard ceiling on how high the base can go: contributions cap at 25 UMA per day, roughly $82,513 MXN a month in 2026. Above that, the percentage doesn't keep climbing.

For the full employer-side breakdown of how this fits into the rest of Mexico payroll, see our guide to managing payroll in Mexico.

How this compares to US payroll burden

US employer payroll tax (FICA, FUTA, SUTA) typically runs 7.65% to 10% of wages, before workers' comp and benefits. Mexico's structure runs three to four times heavier as a percentage, split across more categories, with less flexibility to opt out of any piece of it.

That's not a reason to avoid hiring in Mexico. Labor cost per employee is still substantially lower than the US or Canada even with the heavier social security load on top. It's a reason to model the real number before you quote a client or budget a headcount, instead of discovering the gap after the first payroll run.

Getting this right without an in-country team

Every category above requires registration, monthly calculation, and timely payment to the correct authority, IMSS, INFONAVIT, and the relevant state tax office, with penalties for late or incorrect filings. A Mexican-entity payroll provider carries this as part of the operation, not as a separate compliance project your team has to own from abroad. If your Mexico headcount is still small, a PEO arrangement may fit better than full EOR.

If you're modeling a Mexican hire and want the real number for your specific case, not the general range above, talk to us.