# Simulador IUC — Portugal car tax

Source page: https://valem.run/calculators/portugal/car-tax

Portugal's annual car tax (IUC) for post-2007 cars combines an engine-size and a CO2 component.

**Tax year:** 2026

## How it 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

With Cilindrada of 1,395, this model computes IUC anual of 148.22 EUR.

## Inputs

| Name | Label | Type |
| --- | --- | --- |
| `cc` | Cilindrada (cm³) | number |
| `co2` | Emissões CO2 (g/km, WLTP) | number |
| `anoMatricula` | Ano da 1ª matrícula | number |
| `gasoleo` | Gasóleo | boolean |
| `eletrico` | 100% elétrico (isento) | boolean |

## Sources

- [Código do IUC — Portal das Finanças](https://info.portaldasfinancas.gov.pt) (checked 2026-08-05)
- [Tabelas IUC 2026 — DECO PROteste](https://www.deco.proteste.pt/dinheiro/impostos/noticias/tabelas-iuc-quanto-paga) (checked 2026-08-05)

## What this page claims

The Valem engine reproduces this model's formula through 3 self-test cases. That shows internal consistency, not that the formula matches current law; the cited sources are the evidence for that. Estimate, not tax advice.

## For agents

- Model manifest (formula, constants, test vectors): https://valem.run/calculators/portugal/car-tax.json
- Compute by URL: https://valem.run/calculators/portugal/car-tax.json?cc=1395
- MCP: https://valem.run/mcp/calculators (call `calculate` with calculator `portugal/car-tax`)