Mexico’s personal income tax, the Impuesto Sobre la Renta (ISR), is a progressive tax administered by the SAT. Rather than a single flat percentage, your income is split into brackets, each with a fixed quota plus a marginal rate on the portion of income above the bracket’s floor. This free calculator applies the annual ISR tarifa to your gross income so Mexican employees, freelancers and HR teams can estimate the tax due.
How it works
The annual ISR table (tarifa anual) lists, for each bracket: a lower limit, an upper limit, a cuota fija (fixed amount), and a marginal rate that applies only to income above the lower limit. The calculation is:
- Find the bracket where your taxable income falls between the lower and upper limit.
- Take that bracket’s cuota fija.
- Add the marginal rate multiplied by
(income − lower limit).
The result is your base annual ISR. The highest bracket reaches a 35% marginal rate.
Example
For a taxable income of MXN 400,000, that falls in the bracket starting at 374,837.89 with a cuota fija of 69,662.40 and a 30% marginal rate. The tax is 69,662.40 + 0.30 × (400,000 − 374,837.89) ≈ 77,211. The effective rate is that figure divided by 400,000, around 19.3%, while the marginal rate (the tax on the next peso earned) is 30%.
Notes
This is the base ISR. Real take-home pay also depends on the subsidio para el empleo, personal deductions (medical, mortgage interest, retirement contributions) and IMSS withholding. Use this as a planning estimate, not a substitute for your annual declaración. Everything runs locally in your browser.