Calculating Vehicle Registration Tax (VRT)

Nitrogen Oxide emissions


From 1 January 2020, a second component was added to the calculation of Vehicle Registration Tax (VRT). The Nitrogen Oxide (NOx) charge is combined with the carbon dioxide rates to form the VRT payable. 

More information on how this is calculated can be found in NOx charge.


The NOx levy is chargeable on all Category A vehicles registered after 31 December 2019. Customers registering a vehicle after this date will have to provide evidence of the vehicles NOx emissions to finalise registration. 

Failure to provide this information may lead to delays or a flat charge being imposed.  For more information, please see NOx charge. There are a number of sources where the emissions figure may be obtained.  These are outlined below.  

New vehicles

For new vehicles, the amount of NOx emissions is recorded on the vehicle's Certificate of Conformity (CoC). This document should be obtained from the seller, or from the vehicle's manufacturer.  

A CoC must be uploaded in advance of a vehicle's registration inspection. A manual on uploading an eCOC is available to assist customers.

Used vehicles

The Foreign Registration Certificate (FRC), which is a mandatory document for all used vehicles, may contain a NOx emissions figure.   

United Kingdom (UK) imports may have the NOx figure on the FRC if the document was issued prior to April 2019. This is usually displayed in box V3 of the V5C, the UK registration certificate.

If not present on the FRC, customers are advised to obtain the CoC for the vehicle. This can be obtained by contacting a main dealer, or the manufacturer, directly.

Revenue will also accept official written confirmation from the manufacturer, or an appropriate statutory authority, of the NOx emissions. These will be considered on a case by case basis, depending on the documentation presented.

A NOx figure for Japanese imports can be obtained from the Japanese Ministry of Land, Infrastructure, Transport and Tourism.  

If a NOx figure cannot be provided for a vehicle, then a flat charge will apply.  Further information can be found in NOx charge.

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