How the aguinaldo works
Article 87 of the Federal Labor Law (LFT) gives every employee in Mexico an aguinaldo of at least 15 days of salary, paid before 20 December. If you did not work the whole year, you get the proportional part for the days worked. Many employers grant more days; enter them if yours does.
The first 30 UMA of the aguinaldo are exempt from ISR (LISR art. 93, fr. XIV): $3,519.30 in 2026. The rest is taxed. This calculator withholds that ISR with the article 96 method, as the difference between ISR on your salary plus the taxable aguinaldo and ISR on your salary alone. Employers may also use the optional method of article 174 of the regulation, which gives a slightly different figure.
Worked example
Salary of $20,000 a month, 15 days, whole year worked:
- Daily salary $666.67, gross aguinaldo $10,000
- Exempt $3,519.30, taxable $6,480.70
- ISR $1,384.28, net aguinaldo $8,615.72
For minimum-wage earners, the legal 15 days are fully exempt.
How this works
Daily salary = monthly ÷ 30. Aguinaldo = daily × days × days worked ÷ 365. Exempt = 30 UMA ($117.31 × 30). ISR = ISR(monthly salary + taxable part) − ISR(monthly salary) with the 2026 art. 96 tariff. Minimum-wage earners: the legal 15 days are exempt (LISR art. 93, fr. I).
Frequently asked
When must the aguinaldo be paid?
Before 20 December, by law (LFT art. 87).
Do I get aguinaldo if I quit?
Yes, the proportional part for the days worked in the year, paid in your settlement.
Why can my payslip show a different ISR?
Employers may use the article 174 method of the ISR regulation instead of article 96, which spreads the tax differently.
Sources
- Ley Federal del Trabajo (Cámara de Diputados, texto vigente)
- Ley del Impuesto sobre la Renta (Cámara de Diputados, texto vigente)
- SAT — Anexo 8 de la Resolución Miscelánea Fiscal 2026: tarifas de ISR (DOF 28/12/2025)
- INEGI — Valor de la Unidad de Medida y Actualización 2026 (DOF 09/01/2026)
Reviewed Oct 19, 2026 · test vectors fixtures/calculators/finance/mx/aguinaldo/