Company cars and the reference CO2 emission rate for 2026

What is the new reference CO₂ emission rate ?

The reference CO₂ emission for the calendar year 2026 is set at :

• 70 g/km (down from 71 g/km in 2025) for petrol, LPG, or natural gas powered cars
• 58 g/km (down from 59 g/km in 2025) for diesel powered cars

This emission applies to benefits in kind granted from 1 January 2026.

The benefit in kind (BIK) will increase slightly in 2026

The BIK for company cars is calculated by multiplying these two elements :

• The catalogue value of the vehicle (multiplied by 6/7)
• The CO₂ percentage of the vehicle

The age of the vehicle also influences its catalogue value. This is due to the system of progressive depreciation.

For more information on the progressive depreciation system of the catalogue value, please refer to our theme on Lex4You.

The CO₂ percentage is obtained by adding two elements :

• The base CO₂ percentage of 5.5 %
• The CO₂ emission of the vehicle minus the reference CO₂ emission (result then multiplied by 0.1)

In 2026, the reference CO₂ emissions will be 58 g/km for diesel cars and 70 g/km for petrol cars. This represents a slight reduction compared to 2025, resulting in a minimal increase in the benefit in kind in 2026.

The calculation formula for 2026 in summary

It follows from the above formula that when the reference CO₂ emission rate decreases, the benefit in kind for the car increases.

As information

Regarding electric cars, nothing changes. The calculation of the benefit in kind does not take into account the CO₂ reference values as an electric car does not emit CO₂. Therefore, a minimum percentage of 4% is considered.

An example for illustration

Peter has a company car (VW Golf) valued at 28 600 euros, powered by diesel, which he can use for private purposes. The vehicle emits 98 g of CO₂ per kilometre.

In 2026, the benefit in kind will amount to 194.07 euros per month* :

= [ 28 600 euros × 6/7 ]   ×   [ 5.5 + ( 98 g/km – 58 g/km ) × 0.1 ] / 100

In 2025, the benefit in kind was 192.03 euros per month*:

= [ 28 600 euros × 6/7 ]   ×   [ 5.5 + ( 98 g/km – 59 g/km ) × 0.1 ] / 100

This represents a 1% increase compared to the same new diesel car in 2025.

* In this example, the age coefficient of the car has not been taken into account.

Little impact on the BIK in 2026

The reference CO₂ emission rate corresponds to the average emissions of newly registered cars from the previous year. Since this value tends to decrease, the benefit in kind (BIK) for company cars increases each year.

This decrease in average emissions is explained by the growing popularity of fuel-efficient and electric cars.

However, in 2026, the reference CO₂ emission rate will hardly decrease. The cause : The stagnation of new registrations of electric cars.

It seems that the share of new company cars that are electric has not increased this year. Worse, it may have even slightly decreased between the 1^st and 2^nd quarters.

As a result, your BIK will be hardly impacted this year.

What does Securex do for you?

When calculating the benefit in kind for your company cars, we will obviously take into account this new reference CO₂ emission rate from 2026. For your employees, the decrease in the reference CO₂ emission will lead to a higher taxable benefit in kind and, consequently, in most cases, a slightly lower net salary.

Would you like more information on this topic?

Feel free to contact your Legal Advisor at myHR@securex.be

Source

• Royal Decree of 17 December 2025 amending, with regard to benefits of any kind, the AR/CIR 92 resulting from the personal use of a vehicle provided free of charge, Belgian Official Gazette of 24 December 2025.