Portugal car tax calculator (IUC)
Portugal car tax calculator (Portugal's annual car tax (IUC) for post-2007 cars combines an engine-size and a CO2 component.
Worked example · IUC anual
With Cilindrada of 1,395, this model computes IUC anual of 148.22 EUR. See the full working.
✓ Verified against 3 self-test cases Updated for 2026 · sources checked 2026-08-05
How IUC (single circulation tax) in Portugal is calculated
The IUC (imposto unico de circulacao) is Portugal's annual car tax. For cars registered from July 2007 it combines a component for engine displacement and one for CO2 emissions, scaled by a registration-year coefficient.
Diesel cars carry a surcharge. This model estimates the charge from CO2 bands. Older cars use an engine-and-age table. Estimate, not tax advice.
Worked example
ShowHide the full working: 5 inputs, 5 computed steps
| Inputs | |
|---|---|
| Cilindrada (cm³) | 1,395 |
| Emissões CO2 (g/km, WLTP) | 109 |
| Ano da 1ª matrícula | 2,019 |
| Gasóleo | no |
| 100% elétrico (isento) | no |
| Computed by the engine | |
| Taxa de cilindrada ✓ pinned | 63.74 EUR |
| Taxa de CO2 ✓ pinned | 65.15 EUR |
| Coeficiente do ano ✓ pinned | 1.15 |
| Adicional de gasóleo ✓ pinned | 0 EUR |
| IUC anual ✓ pinned | 148.22 EUR |
Every computed row comes from the engine, run on the inputs above. Rows marked ✓ pinned are also fixed by a published self-test, so a change to the model that moved them would fail its own tests.
Frequently asked questions
How much IUC for a 120 g/km car?
In the illustrative CO2 bands a 120 g/km car is around 120 EUR; higher emitters pay more, and diesels add a surcharge.
What determines the IUC?
Engine size and CO2 for post-2007 cars, scaled by the year of first registration.
Do diesels pay more?
Yes — a diesel surcharge is added to the CO2 component.
Sources
- Código do IUC — Portal das Finanças · checked 2026-08-05
- Tabelas IUC 2026 — DECO PROteste · checked 2026-08-05
Estimate. Not tax advice. The verification badge means the model reproduces the stated formula through 3 self-test cases; the sources support that the formula matches the rules.
Check the arithmetic yourself: how this calculator is verified — the formula behind every derived value, the 3 test cases the engine reproduces, and what the badge does and does not claim. Also available as machine-readable JSON.
Related calculators
Spain IVTM (municipal vehicle tax) · France Carte grise (registration certificate) · Italy Bollo auto (car tax) · Ireland motor tax · Greece Τέλη κυκλοφορίας (road tax)
Also for Portugal: Portugal Salário líquido (net salary) · Portugal Recibos verdes (freelance regime) · Portugal IVA (VAT)
All Portugal calculators · All calculators
Fork this model in the Valem sandbox →
Built with Valem — a live, verifiable calculator you can fork and embed.