Portuguese taxes on cars

In this page: a brief introduction to portuguese vehicle taxes.
Updated: 21th July 2020.
Summary: there are two taxes, ISV, paid when a license plate is delivered and, IUC, paid annually for possessing a vehicle.

Tax principle and some history

In Portugal, cars - and other vehicles such as motorcycles, boats or airplanes - pay essentially two taxes.

One, called Imposto Sobre Veículos or ISV (Vehicle Tax), is paid only once when the vehicle gets a portuguese license plate.

The other, called Imposto Único de Circulação or IUC (Circulation Unique Tax), is paid yearly, for having a (circulation) license plate.

These taxes were implemented in July 2007, replacing "Imposto Automóvel" and "Imposto Municipal sobre Veículos", respectively.
Previously, the vehicle tax ratio was focused on acquisition rather than property.
With the 2007 vehicle tax reform, tax revenue was evenly distributed between property and acquisition, to spread the tax revenue influx, reducing severe impact from highs and lows in the automotive market.

In Portugal, there are no taxes when you buy an used car - you'll only pay the registration fee (about 55€/65€, online/offline).
There are no regional taxes too.

On a side note, when a car gets a license plate number, it gets it for life, meaning that one car (VIN) = one license plate (almost always) forever.
Generally speaking, Portugal doesn't have transit, temporary or personal license plates and as a rule of thumb you can't change your car's license plate number.
Car insurance is a separate process from getting a license plate, your car can have a license plate and, if kept outside public roads, doesn't have to have car insurance.

How ISV works

The ISV for common passenger cars is calculated considering two facts: engine cubic capacity (displacement) and CO2 emissions.
Both are declared by the manufacturer through a document called Certificate of Conformity or by the Department of Vehicles' (IMT or Instituto da Mobilidade e dos Transportes) Homologation.

The math goes like this:

(engine cc * tax per cc - fixed deductible amount)
+
(CO2 g/km * tax per g/km - fixed deductible amount).

There are several tax brackets for engine displacement and several tax brackets for CO2 emissions.
The purpose of these brackets is to charge significantly more tax if the vehicle has more cc or emits more CO2. The government official version is that ISV tries to tax the most polluting vehicles.

More about this: ISV tax rate tables (in portuguese).

There are several tax reductions for several types of vehicles or owners.
If you're moving to Portugal and you bring your car with you, you can be exempted from ISV.

Some vehicles' tax calculation doesn't consider CO2 emissions (goods/commercial vehicles, motorcycles).
Hybrid or plug-in cars have a discount, electric cars don't pay any ISV.
There is a 500€ surcharge for diesel vehicles that emit more than 0,002~0,001g/km of particles (meaning, all diesel cars without diesel particulate filter - DPF).
Other tax breaks include cabs and car rental companies. The state itself and several other private institutions or individuals (firefighters, solidarity associations, persons with disabilities, diplomatic or UE staff) don't pay any ISV on all or some vehicles.

More about this: ISV legislation (in portuguese).

ISV is owed for new and used vehicles. Used vehicles imported from an UE country benefit from an age discount, between 10% (up to 1 year) and 80% (more than 10 years), but only for the engine displacement tax component. Any imported used vehicle pays the CO2 tax component as if it was new - there's no age discount.
Used vehicles imported from any other country (Switzerland or the USA for example) don't get any age discount on ISV and also have to pay 23% VAT (IVA), on top of any other customs duty, which range from 0% to 10%.

More about this: ISV calculator (in portuguese).

In general, ISV lets us be one of the leading countries in low car CO2 emissions. In everyday life, we have an underpowered car fleet. Cars with between 1.0 (gasoline) and 1.6 liters (diesel) of engine displacement represent the major share of cars sold.
We pay something like 500€~1.500€ of ISV for gasoline vehicles and 2.000€~4.000€ for diesel vehicles. Contrary to what these numbers may suggest, we are a diesel nation - fuel tax (ISP) is heavier on gasoline than on diesel and, corporate tax laws give more tax deductions to diesel than to gasoline.

How IUC works

IUC, the yearly tax, is based on the same principles. More cc, more CO2, more tax to pay.
Yet, there is a major difference between two classes of vehicles. Those that were registered before July 2007, benefit from a very low tax, because IUC was implemented on that date.
Previous to IUC, average cars used to pay a yearly tax of just 10€~50€.
After IUC was implemented, this yearly tax was increased to an average of 100€~300€. The most polluting vehicles, diesel +2.500cm3 and +250g/km CO2 pay something like 1.000€ every year.
When buying or importing a car, consider those that have a low engine displacement and low CO2 emissions.

More about this: IUC tax rates tables (in portuguese).

IUC is payable up to the end of the month of the portuguese license plate.
Example: if a car gets its license plate on 8th March 2017, one must pay IUC until 31st March in any given year. Nonetheless, although IUC is due yearly, only its payment is distributed along the year, to avoid payment peaks or last minute rushes.

There is no longer a "tax paid stamp" that you need to stick in the car. The police and transit authorities don't have any legal grounds to require any proof that the tax was paid. If you pay or not, it's only a matter of business between you and Autoridade Tributária (Tax Authority). However, Autoridade Tributária can and will issue a mandate to apprehend any car that is past due on IUC (something that, to my knowledge, is very rare).

More about this: IUC FAQ (Frequently Asked Questions) (in portuguese).

The tax is calculated considering the same figures of ISV calculation: engine cc and CO2 emissions. There are two tax tables, one for each figure. Then, there is a coefficient factor to penalize younger cars. From 2017 there is also a new additional surtax for cars with more than 180g/km of CO2 emissions.
Diesel cars also pay a surtax. This surtax was meant to be temporary but, until now, it prevails.

Goods or commercial vehicles pay accordingly to their gross weight.
Motorcycles pay accordingly to their engine displacement and age (CO2 isn't considered).

More about this: IUC calculator (in portuguese).

There are tax breaks for some persons (disabled) or entities (state vehicles, solidarity associations, etc.).

The IUC tax is due until one cancels the vehicle's license plate, meaning, it's a tax for the life of the car.

More about this: IUC legislation (in portuguese).

There is a common confusion among imported used cars regarding IUC. The tax is payable, as mentioned above, until the end of the license plate's month.
But, some years ago, because we were importing too many used cars from UE countries (Germany mainly), there were concerns that these vehicles didn't match the wanted vehicle profile that Portugal was supposed to have. Let's say it another way: we were importing too much junk. So, the government changed our license plates layout to add a yellow side strip that mentions the month and year of the first license plate of the car, be it portuguese or not.
So, today, we have a tax that's payable until the end of the portuguese license plate's month but, in the physical license plate, the one that you find in the car, you can have a completely different month.
Predictably, this measure didn't accomplish its objective and in 2020, when a new format of license plates was issued because the old one was running out (dashes were dropped and the letter/number combination was changed to AB 12 CD), the yellow side strip with the car's first registration date was also dropped. As it is allowed for already issued license plates to change to the new format, you can see in the streets old cars with a new license plate format but with the old letter/number combinations (12 AB 34 and 12 34 AB).

Moreover, you can have a 2005 car, that was imported in 2010, that will pay IUC as a portuguese 2010 car (the tax's higher), and not a 2005 car, because the IUC is payable according only to the portuguese license plate date if its first license plate (registration) isn't from an UE/EEA country.
The only place where you can check the date and origin of the first plate is in the DUA (Documento Único Automóvel - we have some affection for initials), the vehicle registration certificate.
So, if you bring a 2000 car from an UE/EEA country you'll be paying IUC accordingly to the first license plate date but, if you bring the same car from a non-UE/EEA country, such as the USA or Russia, you'll pay IUC as if it was new in Portugal.

Imposto Sobre Veículos
Imposto Único de Circulação

IUC - Imposto Único Circulação

ISV - Imposto Sobre Veículos