Calculator methodology
Last updated: 2026-04-24
We believe a calculator you can't audit is just a guess. Every formula, table, and assumption used on this site is documented below.
IRS 2026 — Madeira vs mainland
Marginal-sum progressive method. Mainland rates from PwC Guia Fiscal 2026. Madeira rates computed as mainland × 0.70 (the max 30% regional reduction per DLR 8/2025/M). Cumulative deduction ('parcela a abater') not applied by default — the calculator sums tax per bracket directly.
Recibos verdes — simplified regime
Taxable income = revenue × (1 − coefficient). Coefficient 0.75 for services (CIRS art. 31 default). SS = monthly revenue × 0.70 × 0.214. Bounded by €20/mo minimum and 12×IAS maximum (€6,445.56 in 2026). First-year exemption applied via checkbox. IVA threshold = €15,000 annual (2026).
IBC / Zona Franca savings
Taxable profit up to the job-bracket cap taxed at 5%. Excess taxed at standard IRC 19% (or 15% PME first €50K if PME flag enabled). Cumulative savings over 7 years (2026-2033) assume the rate holds until the extension sunsets.
Crypto 365-day tracker
Client-only, no backend. Per lot: heldDays = disposalDate − acquisitionDate (calendar days). If heldDays ≤ 365 → 28% of gain. Otherwise → 0%. Does NOT auto-detect swap resets — user must enter correct acquisition date per lot.
IFICI quiz
5 boolean answers → outcome. All 5 true → qualify. ≤ 2 fails and at least one of {residentAfter2024, notResident5Years} true → borderline. Otherwise → no. Simplified: real IFICI approval depends on documentation review by AT.
What we do NOT include
- Specific deductions (health, education, supported VAT, life insurance, etc.) — too variable to model generically.
- Tributações autónomas on corporate vehicles.
- Derrama municipal (local IRC surtaxes up to 1.5%).
- Double-taxation treaty provisions — depend on specific country combinations.
Refresh commitment
Brackets, IAS, IRC rate reductions update every January. Mid-year rule changes (AT circulars, DLRs) update when published. Every page shows the last-verified date.