About the Mexico ISR Calculator
This Mexico ISR calculator (calculadora ISR) estimates what an employee keeps from a monthly salary in 2026. It applies the monthly ISR withholding tariff from Anexo 8 of the Resolución Miscelánea Fiscal 2026, subtracts the subsidio para el empleo for lower salaries, and deducts the worker’s IMSS social security quotas, leaving your estimated sueldo neto.
It helps employees checking a recibo de nómina, candidates comparing offers in pesos, and small employers estimating payroll. IMSS quotas are based on your salario base de cotización (SBC), which the calculator derives from your salary with the legal integration factor for aguinaldo and prima vacacional.
Assumptions: all salary is taxable ordinary income paid monthly; the employment subsidy is 15.02% of the monthly UMA (MX$535.65 from February 2026) for monthly income up to MX$11,492.66, applied only against ISR; IMSS uses UMA MX$117.31, 30.4 days per month and the SBC cap of 25 UMA. Workers earning only the general minimum wage (MX$315.04 a day) have no ISR withheld and their IMSS quota is paid by the employer. Exempt benefits, overtime, savings funds and the border-zone minimum wage are not modelled.
With the default inputs, the estimated net monthly pay (sueldo neto) is MX$17,076.77. Change any value above to recalculate instantly.
How to use the mexico isr calculator
- 1Enter your gross monthly salary as shown in your contract.
- 2Adjust aguinaldo days, vacation days and prima vacacional if your employer pays more than the legal minimum.
- 3Keep IMSS on to see the worker quotas deducted from payroll.
- 4Read your estimated net pay, then the ISR, subsidy and IMSS breakdown.
Formula and method
ISR is withheld monthly using the article 96 tariff: find the bracket whose lower limit is just below your income, take the fixed fee and add the bracket rate on the excess. For monthly income up to MX$11,492.66 the employer credits the subsidio para el empleo, 15.02% of the monthly UMA, against that ISR; it cannot create a refund.
The worker’s IMSS quotas are percentages of the daily salario base de cotización (SBC): 0.25% for cash sickness benefits, 0.375% for pensioners’ medical expenses, 0.625% for disability and life and 1.125% for old-age and severance (cesantía y vejez), plus 0.40% on the part of SBC above three UMA. SBC integrates the yearly aguinaldo and prima vacacional into daily pay and is capped at 25 UMA.
- UMA
- Unidad de Medida y Actualización: MX$117.31 daily, MX$3,566.22 monthly from Feb 2026
- SBC
- Salario base de cotización (integrated daily wage)
- Prima
- Prima vacacional as a fraction of vacation pay (at least 25%)
Worked examples
MX$20,000 a month with legal-minimum benefits
MX$20,000 falls in the 21.36% bracket starting at MX$17,533.65: MX$1,856.84 + 21.36% × MX$2,466.35 = MX$2,383.65 of ISR, with no subsidy at this income. The SBC is MX$657.89 × 1.0493 = MX$690.34 a day; 2.375% of that plus 0.40% of the excess over 3 UMA, times 30.4 days, is MX$539.58 of IMSS, leaving MX$17,076.77.
MX$11,000 a month (subsidy applies)
ISR per tariff is MX$420.95 + 10.88% × (MX$11,000 − MX$7,168.52) = MX$837.82. Income is below MX$11,492.66, so the 2026 subsidy of 15.02% × MX$3,566.22 = MX$535.65 is credited, leaving MX$302.17 of ISR withheld.
MX$60,000 a month
Income is in the 30% bracket from MX$55,736.69: MX$10,457.09 + 30% × MX$4,263.31 = MX$11,736.08 of ISR. With IMSS switched off, net pay is MX$48,263.92.
Frequently asked questions
How is ISR on salary calculated in 2026?+
Employers use the monthly tariff in Anexo 8 of the RMF 2026: subtract the lower limit of your bracket from your taxable income, multiply by the bracket rate (1.92% to 35%) and add the fixed fee. The employment subsidy is then credited if you qualify.
How much is the subsidio para el empleo in 2026?+
From February 2026 it is 15.02% of the monthly UMA, about MX$535.65 a month, for workers whose monthly income does not exceed MX$11,492.66. In January 2026 the rate was 15.59% of the 2025 UMA. It is only credited against ISR and is never paid out as cash.
Do minimum wage workers pay ISR?+
No. Article 96 of the ISR law exempts workers who earn only the general minimum wage (MX$315.04 a day in 2026) from withholding, and article 36 of the Social Security Law makes the employer pay their IMSS worker quota.
What IMSS quotas does the worker pay?+
The employee pays 0.25% (cash sickness benefits), 0.375% (pensioners’ medical care), 0.625% (disability and life) and 1.125% (old-age and severance) of SBC, plus 0.40% on SBC above three UMA. For most salaries this totals about 2.4% to 2.8% of pay.
What is the salario base de cotización (SBC)?+
SBC is the integrated daily wage used for IMSS. It adds the daily value of aguinaldo, prima vacacional and other fixed benefits to your daily salary. With legal minimum benefits (15 days of aguinaldo, 12 vacation days at 25%) the integration factor is about 1.0493.
Is aguinaldo taxed?+
Aguinaldo is exempt from ISR up to 30 UMA (about MX$3,519 in 2026); the rest is taxable. This calculator handles regular monthly salary only, so calculate aguinaldo and PTU separately.
Tax results are estimates based on published rules and simplified assumptions. They are not tax advice — check official guidance or a tax professional for your situation.