When a professional dealer imports a used car to Portugal, the ISV (Imposto Sobre Veículos) is often the line that separates a profitable deal from a loss-making operation. Most of this tax is determined by just two pieces of information already available in the vehicle’s documents: its age (date of first registration) and CO₂ emissions.
Reading these two values correctly before bidding allows you to predict the tax cost with high accuracy. This article explains how these two levers work in 2026, the European legal framework that made the system fairer, and how to calculate the ISV before purchasing.
ISV in two parts: engine displacement + environmental component
The ISV is the sum of two independent components:
- Engine displacement component — based on the engine capacity (cm³).
- Environmental component — based on official CO₂ emissions (g/km).
For the vast majority of cars from 2019/2020 onwards, the environmental component uses WLTP values (more stringent). Older cars use NEDC values.
Two cars with the same engine can have very different ISV amounts precisely because of the CO₂ figure — this is where profit margins are won or lost.
Age-based reduction: the table that changed everything
Since 1 January 2025 (Law 45-A/2024, OE2025), Portugal unified the age-based reduction table. The same discount percentage now applies to the entire ISV (both components). Previously, there were separate tables — do not use the old tables still circulating online.
Age Reduction Table (2026) — Art. 11.º of the ISV Code
Vehicle Age ISV Reduction
Up to 1 year 10%
1–2 years 20%
2–3 years 28%
3–4 years 35%
4–5 years 43%
5–6 years 52%
6–7 years 60%
7–8 years 65%
8–9 years 70%
9–10 years 75%
Over 10 years 80%
The older the car, the greater the discount on the total ISV. This partially offsets the typically higher CO₂ emissions of older vehicles.
Why the environmental component now takes age into account (the CJEU history)
For years, Portugal applied the age reduction only to the displacement component and charged the full environmental component regardless of the vehicle’s age. Two rulings by the Court of Justice of the European Union changed this:
- C-200/15 (16 June 2016) — Portugal’s depreciation table did not reflect the real residual value of used vehicles, breaching Article 110 TFEU.
- C-169/20 (2 September 2021) — even after the first correction, Portugal continued to discriminate against imports by not applying any reduction to the environmental component. Another breach of Article 110 TFEU.
Portugal aligned its legislation, and the single unified table (OE2025) completed the fix.
Practical implication for professionals: imported used cars are no longer penalised on the CO₂ component compared to equivalent domestic vehicles. Those who overpaid in previous years may be entitled to a refund through a gracious claim, ex officio review, or CAAD arbitration.
How to read the ISV before buying (examples)
Always use the official simulator on the Portal Aduaneiro for exact figures, but here are typical profiles (approximate values for 2026):
- Recent low-CO₂ car (e.g. 1.0 petrol, 3 years old, 120 g/km WLTP) Moderate ISV base + small reduction (28%) → predictable and manageable tax.
- Older diesel (e.g. 7 years old, 160 g/km) Higher base but strong reduction (60%) → often worthwhile if the purchase price is good.
- BEV (100% electric) Fully exempt from ISV, regardless of age.
Key takeaway: always assess age + CO₂ + engine displacement before bidding. A car that looks cheap can become expensive after the DAV.
Electric, plug-in hybrid and conventional hybrid vehicles in 2026
- BEV (pure electric) → full ISV exemption.
- PHEV (plug-in hybrids) → pay only 25% of the ISV (75% reduction), provided they have a grid-rechargeable battery, electric range ≥ 50 km, and CO₂ ≤ 50 g/km (Euro 6) or ≤ 80 g/km (Euro 6e-bis).
- Non-plug-in hybrids → no discount, taxed as conventional combustion engines.
Qualifying PHEVs remain an excellent option for stock, especially in mid-range segments.
Where to find stock with the right profile
To work with solid margins, you need volume and precise filters (age, WLTP CO₂, Euro standard, fuel type). This access is provided by professional platforms such as eCarsTrade, leilões online para profissionais, where you can filter exactly by these criteria across graded European stock.
Legalising an imported car: DAV, ISV, inspection, registration
- Vehicle entry → issuance of the DAV (Declaração Aduaneira de Veículo) within 20 working days.
- ISV payment via DUC.
- Type B inspection.
- Legalisation at IMT and registration (the full process usually takes around 60 days).
For the complete, up-to-date step-by-step import and legalisation guide:
How to import and legalise a car in Portugal – Complete Guide
Conclusion
In 2026, ISV is predictable when you correctly read the age and CO₂ before buying. Source stock with the profile that protects your margin, budget the tax upfront, and avoid surprises at the DAV stage.
Imported used cars are no longer penalised compared to domestic ones — those who know how to read the numbers and use the right tools have a clear advantage in the market.