Every CLT employee earns 30 days of paid vacation per acquisitive period. For the days you actually take as leave, you receive your normal daily rate plus a mandatory constitutional additional of one-third, guaranteed by Article 7º, XVII of the Constitution. Both the base vacation pay and the 1/3 additional have salary nature, so both INSS and IRRF apply, a point the STF settled definitively in Tema 985.
Up to 10 of those 30 days can instead be converted to cash, called abono pecuniário. That cash-out is compensatory rather than salary in nature, so it's exempt from both INSS and IRRF entirely. The one wrinkle: the 1/3 additional calculated on the sold days remains IRRF-taxable, per Receita Federal's own guidance (Solução de Consulta COSIT nº 209/2021), even though it stays INSS-exempt. That means INSS and IRRF are calculated on two different bases here, not one shared figure like the 13º salário.
This calculator reuses the exact same progressive INSS bands, IRRF tabela progressiva mensal, and Lei 15.270/2025 redutor that power the flagship Brazil Salary Calculator and the 13º Salário Calculator, applied to the correct férias-specific taxable base rather than a re-derived formula.