Some accessories, those which affect weight, rolling resistance and aerodynamics, have an effect on CO2 emissions according to the WLTP standard now in use. You should therefore be aware that this can affect the taxation of your vehicle. The CO2 value used by the regional tax authorities is that shown on the certificate of conformity and reproduced on the registration certificate. For second hand cars or cars approved before 2021, this may still be the NEDC standard that does not take options into account. In this case, the accessories have no effect. In some parts of the country, CO2 does not yet affect car taxation.
As part of the CO2 values calculated by the mandatory WLTP norm since 2021, the wheel size, the installation of a towing system, a panoramic roof, an ultra-complete comfort package or air suspension will add a few grams to the CO2 values of your vehicle. One of the most affecting accessories are the rims. More specifically, their diameter. By choosing 16" rather than 17" or 18", for example, you could save tens of euros in taxes.
You live in in the Brussels Region
For 2021, the registration tax and road tax do not take into account CO2emissions. The calculation is based solely on capacity and power. Your choices regarding options and accessories will therefore not affect taxation with the WLTP standard. This could change by 2024 with the reform of car taxation in Brussels.
You live in Wallonia
For 2021, so long as you do not reach 146g CO2/km, there is no eco-penalty to pay in addition to the road tax. Once this limit is reached, the amount increases in steps. 1g more may require you to pay €100 or €75 extra tax. For the registration tax and the annual road tax, on the other hand, CO2 plays no role. It is the power and capacity that determine the tax amount. In 2023, Walloon taxation will use a formula that takes into account CO2emissions, as well as the weight of the vehicle. The choice of options will then affect when this new taxation applies.
You live in Flanders
CO2 is, with fuel, power and engine capacity, one of the parameters taken into account by formulas for calculating the registration tax and road tax. Moreover, any new car tax is calculated on the basis of the WLTP, which has only been taken into account since 2021. Each gram of CO2 therefore affects the price to be paid. You should therefore be careful when choosing options.
You are self-employed or a company
The CO2 value affects the rate of deduction of car costs, regardless of your region. Every gram of the CO2 value can therefore affect the percentage deduction. If the vehicle’s certificate of conformity states an NEDC value, it can be used. In this case, the choice of options will not affect the CO2values, unlike the WLTP, the only standard in force for vehicles approved since 2021.