Principal Software Engineer Day Rate Calculator: Mexico 2026

Your tax treatment depends on your SAT tax regime. RESICO (Régimen Simplificado de Confianza): a flat, non-marginal ISR rate of 1.92%-2.5% applies directly to gross revenue based on your monthly income band, with no expense deductions. Actividad empresarial y profesional ("honorarios"): you deduct real business expenses first, then the standard progressive Art. 96 LISR tarifa (1.92%-35%) applies to net income, the same bracket table salaried employees use. The calculator above compares both side by side.

Retention rates vary by regime and income level. RESICO often nets more at lower-to-mid revenue thanks to its flat, low rate, but actividad empresarial can win at higher revenue with substantial deductible business expenses, since its marginal rates only bite the portion of income above each band. Neither regime includes IMSS coverage by default, independent workers who want it enroll and pay voluntarily.

RESICO is simpler (no bookkeeping for deductions) and often nets more at typical IT contractor rates, but the flat rate scales with total revenue rather than net income, so it can lose its edge once you have significant deductible expenses. The calculator above shows the exact net difference at your rate so you can weigh the trade-off concretely.

At MX$5951/day over 220 billable days, the gross annual contract income is MX$1309K. This is a 33% gross premium over the Principal Software Engineer permanent salary median of MX$986K/year. The premium compensates contractors for self-funded IMSS, holiday pay, sick pay, aguinaldo, and business overheads a permanent employer covers on an employee's behalf.