How it works
In Mexico an employee on payroll loses two things from the gross salary: ISR (impuesto sobre la renta), withheld by the employer every month, and the employee share of IMSS social security. There is no state income tax on employees; the state payroll tax (impuesto sobre nómina) is paid by the employer. This page uses the 2026 rules: the monthly tariff of Annex 8 of the Resolución Miscelánea Fiscal 2026 (inflation-updated by a factor of 1.13213), the subsidy decree published in the DOF on 31 December 2025 and the UMA published by INEGI.
ISR: monthly tariff and subsidio para el empleo
The tariff has 11 brackets from 1.92% to 35%. Tax = fixed fee + (monthly salary − lower limit) × rate of the bracket; for example above 17,533.65 pesos the fixed fee is 1,856.84 and the rate 21.36%. Workers earning up to 11,492.66 pesos a month then get a subsidy of 15.02% of the monthly UMA (3,566.22), which is 535.65 pesos, applied against their ISR. If the subsidy is bigger than the tax, the tax is zero and the difference is not paid out. Because the rule is all-or-nothing, a salary just above 11,492.66 pesos can leave you with slightly less net pay than a salary just below it.
IMSS employee quotas
The base is the daily contribution salary (SBC) capped at 25 UMA (2,932.75 pesos a day). The employee pays 0.25% (cash benefits), 0.375% (pensioners' medical care), 0.625% (disability and life) and 1.125% (retirement, cesantía and vejez) of the SBC, plus 0.40% on the part of the SBC above 3 UMA (351.93 pesos a day). The SBC is normally the daily wage times 1.0493, which adds the legal minimum aguinaldo, vacation days and vacation premium; choose the second option if your employer registers you with the plain salary.
Worked example
Monthly gross salary of 25,000 pesos with statutory benefits: ISR is 3,451.65 (1,856.84 + 7,466.35 × 21.36%, no subsidy at this level), IMSS is 685.16, and the net monthly pay is 20,863.19 pesos. At 15,000 pesos: ISR 1,402.82, IMSS 393.98, net 13,203.20. At 10,000 pesos: ISR 729.02 before the subsidy and 193.37 after it, IMSS 249.21, net 9,557.42.
What this calculator leaves out
It assumes the whole salary is taxable fixed pay paid monthly, without exempt allowances, Infonavit deductions, savings funds, overtime, bonuses or aguinaldo, and no deductions of the annual return (personal deductions such as medical fees). Your employer's payroll can differ by a few pesos because of the number of days in the pay period.