NOx levy rates 2026 — the tiers
The NOx levy on a Category A (passenger) car is worked out tier by tier on the vehicle's NOx output in mg/km. Pure electric vehicles are exempt. If you cannot supply a NOx figure, Revenue applies a flat default cap instead. All figures verified against revenue.ie.
| NOx tier | Levy rate |
|---|---|
| 0–40 mg/km | €5/mg |
| 41–80 mg/km | €15/mg |
| 81+ mg/km | €25/mg |
Default caps (no NOx data): €4,850 for diesel, €600 for everything else. Always supply the NOx figure from your Certificate of Conformity to be charged the tiered levy instead.
Estimate only — verify with Revenue/SEAI before committing.
The NOx levy is just one part of the bill. Use our VRT calculator to see the full VRT + NOx total for a specific car.
NOx levy — frequently asked questions
What is the NOx levy in Ireland?
The NOx levy is an emissions-based charge added to Vehicle Registration Tax (VRT) on every Category A passenger car registered in Ireland, except pure electric vehicles. It is charged on the car’s nitrogen oxide (NOx) output in mg/km and is paid alongside VRT at the NCTS centre when the vehicle is registered.
How is the NOx levy calculated?
The NOx levy is tiered: €5 per mg/km for the first 40 mg/km, €15 per mg/km for 41–80 mg/km, and €25 per mg/km for anything above 80 mg/km. For example, 100 mg/km costs €5×40 + €15×40 + €25×20 = €1,300. Enter your exact NOx figure above for the precise charge.
What happens if I can’t provide a NOx figure?
If you cannot supply a NOx reading, Revenue applies the maximum default cap: €4,850 for a diesel vehicle and €600 for everything else. This is far higher than most real NOx levies, so always provide the NOx mg/km figure from your Certificate of Conformity to avoid the default.
Do electric cars pay the NOx levy?
No. Battery-electric vehicles produce zero NOx, so they are exempt from the NOx levy entirely — the charge is €0. Plug-in hybrids and conventional hybrids are not exempt, because their petrol or diesel engine still emits NOx, though hybrid NOx figures are usually low.
Where do I find my car’s NOx figure?
The NOx figure in mg/km is printed on the Certificate of Conformity (CoC) and, for UK imports, can often be confirmed from the V5C and manufacturer data. Supplying this figure at registration is what lets Revenue charge the tiered levy instead of the €4,850 (diesel) or €600 (other) default cap.
— The Autoza Team