Company vehicles - NSSO: the CO2 contribution on 1 January 2023

Author: Anne Ghysels (Legal Expert)
Read time: 3min
Publication date: 13/12/2022 - 14:18
Latest update: 13/12/2022 - 14:19

Indexation of the CO2 contribution on 1 January 2023

As of 1 January 2023, the formula for calculating the solidarity contribution payable by employers on company vehicles will be adapted shortly.

On 1 January 2005, a solidarity contribution based on CO2 emissions and payable by the employer was introduced for commercial vehicles. This employers' levy which is calculated on a monthly basis, shall be paid per quarter to the NSSO within the same deadlines as those that apply for the social security contributions for employees.

More specifically, the levy is calculated on the basis of the car's CO2 emission rate and a flat-rate amount that depends on the type of from fuel and is indexed on 1 January of each year. From 1 January 2023, the employer solidarity contribution on company vehicles will be calculated on the basis of the following formula:

Fuel of type

Basic formula

Indexation Coefficient


{[(CO2 emission rate x €9) – 768] / 12} x

Multiplied by 171.64, then divided by 114.08


{[(CO2 emission rate x €9) – 600] / 12} x


{[(CO2 emission rate x €9) – 990] / 12} x


€ 20,83 x

Moreover, from 1 January 2023, the amount of the CO2 contribution may under no circumstances be less than 31.34€ for non-electric cars.


An employee is using a company car SKODA SUPERB, 1.6 CRDTI Classic for private ends. The car is equipped with a diesel engine. The CO2 emission rate for this category of cars is 130 g/km.

CO2 contribution from 2023: 71.47€ per month ([Image removed.((130 x 9) - 600) / 12) x 171.64) / 114.08]), or 214.40€ per quarter.

These amounts are communicated subject to confirmation by the NSSO.

Reminder: CO2 emission to be used from 1 January 2021

From 1 January 2021, the following value must be taken into account when calculating the CO2 contribution:

  • the NEDC 1.0 CO2 value when the vehicle only has an NEDC value;
  • the WLTP CO2 value when the vehicle only has a WLTP value;
  • the NEDC 2.0 CO2 value or the WLTP CO2 value (free choice) if the vehicle has both an NEDC 2.0 CO2 value and a WLTP CO2 value.

If the vehicle has two CO2 emission rates it is best to choose the lowest CO2 emission rate for the calculation of the CO2 contribution.

Strong increase of the CO2 contribution as of 1 July 2023

As part of the greening of mobility, the government has decided that the CO2 contribution will be increased as of 1 July 2023 on the basis of a coefficient and for certain vehicles. The minimum CO2 contribution will also be increased.

For company cars purchased, rented or leased as of 1 July 2023:

The CO2 contribution will be multiplied by the following coefficients:

As of:

Increase factor / coefficient


X 2.25


X 2.75


X 4.00


X 5.50

In addition, the minimum CO2 contribution will increase:

As of:

Minimum contribution (before indexation)


20.83 € (31.34 € after indexation)


23.41 €


25.99 €


28.57 €


31.15 €

For company cars purchased, rented or leased before 1 July 2023:

The CO2 contribution is not to be multiplied by a coefficient. It is calculated solely on the basis of the formula explained at the beginning of this Infoflash.

Source: Act of 25 November 2021 organising the fiscal and social greening of mobility, Belgian Official Gazette 03.12.2021



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