Progressive INSS, the IRRF base, the dependent deduction, the new Law 15,270 reduction and the transport-voucher and health-plan deductions, with two worked examples.
Step 1: INSS band by band
Net salary is gross minus INSS, IRRF and the agreed deductions (transport voucher, health plan, alimony). The first cut is INSS, calculated progressively under the 2026 table: 7.5% up to R$ 1,621.00; 9% from R$ 1,621.01 to R$ 2,902.84; 12% from R$ 2,902.85 to R$ 4,354.27; and 14% from R$ 4,354.28 to R$ 8,475.55. Each band pays only its own rate, and the maximum deduction is R$ 988.09.
Example with a R$ 4,500.00 salary: R$ 121.58 in the first band, R$ 115.37 in the second, R$ 174.17 in the third and 14% of R$ 145.73 in the fourth, or R$ 20.40. Total INSS: R$ 431.52.
Step 2: the IRRF base and table
The tax base is gross minus INSS, minus R$ 189.59 per dependent and minus court-ordered alimony. The monthly table applies to it: exempt up to R$ 2,428.80; 7.5% up to R$ 2,826.65 (deduction R$ 182.16); 15% up to R$ 3,751.05 (R$ 394.16); 22.5% up to R$ 4,664.68 (R$ 675.49); 27.5% above (R$ 908.73).
In the R$ 4,500.00 example with no dependents, the base is R$ 4,068.48. In the 22.5% bracket: R$ 915.41 minus R$ 675.49 gives R$ 239.92 of tax under the table.
Step 3: the 2026 reduction
Since January 2026 Law 15,270/2025 applies: if taxable income for the month is up to R$ 5,000, the reduction equals the tax and IRRF drops to zero. Between R$ 5,000.01 and R$ 7,350 the reduction is R$ 978.62 minus 0.133145 times the income. Above R$ 7,350 there is no reduction.
Since R$ 4,500.00 is below R$ 5,000, the R$ 239.92 from step 2 is wiped out. Net before agreed deductions: R$ 4,500.00 minus R$ 431.52, or R$ 4,068.48.
Second example, a R$ 8,000.00 salary: INSS of R$ 921.51, base of R$ 7,078.49, tax under the table of R$ 1,037.85, no reduction because income exceeds R$ 7,350. Net before agreed deductions: R$ 6,040.64.
Step 4: agreed deductions and what is not deducted
Transport voucher: up to 6% of base salary, or the actual fare cost if lower. Health and dental plan: the co-payment set in the policy. Alimony: the percentage in the court order, which also lowers the IRRF base. Salary advance: the amount already paid in the month.
FGTS deducts nothing: the 8% is deposited by the employer on top of the salary. Vacation and 13th-salary accruals are not deductions either; they only appear on the company cost side.
Check without redoing the maths
The Avos net salary calculator applies exactly these 2026 tables, including the Law 15,270 reduction, and accepts dependents and other deductions. The same engine runs payroll in the product, so what the calculator shows is what lands on the payslip.