WLTP VRT Calculator 2026
Calculate VRT using WLTP emissions - real-world driving conditions
Calculate WLTP VRT →WLTP VRT Calculator
Calculate VRT using WLTP (Worldwide Harmonized Light Test Procedure) emissions data for accurate 2026 rates.
WLTP vs NEDC - What's the Difference?
WLTP replaced the old NEDC test in 2017 because NEDC was completely unrealistic. Real-world driving showed cars using 20-40% more fuel than NEDC suggested. WLTP isn't perfect, but it's much closer to reality.
WLTP Advantages
- Real-World Conditions: Tests include hills, acceleration, braking
- Variable Speeds: From 0-131 km/h vs NEDC's max 120 km/h
- Longer Tests: 30 minutes vs NEDC's 20 minutes
- Individual Testing: Each variant tested separately
- Optional Equipment: Air con, larger wheels affect results
Impact on VRT
- WLTP figures are typically 10-25% higher than NEDC
- This means higher VRT for the same car
- But WLTP better reflects actual fuel costs
- Revenue uses whichever test was current when car was certified
WLTP Reality Check
WLTP is closer to real-world emissions, but still optimistic. Expect your actual fuel consumption to be 10-20% higher than WLTP suggests.
Understanding WLTP Test Phases
Four WLTP Phases
| Phase | Speed Range | Duration | Represents |
|---|---|---|---|
| Low | 0-56 km/h | 589 seconds | Urban driving |
| Medium | 0-76 km/h | 433 seconds | Suburban driving |
| High | 0-97 km/h | 455 seconds | Rural roads |
| Extra-High | 0-131 km/h | 323 seconds | Motorway driving |
Factors Affecting WLTP Results
- Vehicle Weight: Heavier cars use more fuel
- Aerodynamics: Drag coefficient affects high-speed efficiency
- Tire Size: Larger wheels increase rolling resistance
- Optional Equipment: Air conditioning, sunroof add weight
- Transmission: Manual vs automatic vs CVT differences
WLTP Variants
The same car model can have multiple WLTP ratings depending on engine, transmission, and equipment. Always use the specific figure for your exact variant.
What Is WLTP and Why Does It Matter for VRT?
WLTP stands for Worldwide Harmonized Light Vehicle Test Procedure. It is the standard way the European Union measures how much CO2 a car emits and how much fuel it uses. Every new car sold in Europe since September 2018 has to pass a WLTP test before it can be registered. If you are importing a car into Ireland, the WLTP figure on the vehicle's certificate of conformity is what Revenue uses to calculate your VRT.
Before WLTP, Ireland used the older NEDC (New European Driving Cycle) figures. NEDC was developed in the 1980s and last updated in the 1990s. The test was done on a rolling road with very gentle acceleration, no air conditioning running, and a fully warmed engine. It bore almost no resemblance to how people actually drive. A car might officially emit 120 g/km under NEDC but produce 160 g/km or more on a real Irish road with hills, traffic, and cold starts.
WLTP was designed to fix that. The test is longer, covers more speed ranges, uses more realistic driving behaviours, and accounts for things like tyre size, optional equipment, and vehicle weight. For VRT purposes, this matters because the CO2 figure directly determines what rate you pay. A higher WLTP number puts you in a higher VRT band, which can mean hundreds or even thousands of euro difference on the same car.
If you are buying a car that was first registered after September 2018, Revenue will almost certainly use the WLTP figure. Older cars use NEDC. Some cars from the transition period (roughly 2017 to 2019) might have both figures listed. In those cases, Revenue generally uses whichever test was mandatory at the time of the car's original registration.
WLTP Testing Process Explained
The WLTP test happens on a chassis dynamometer, which is basically a set of rollers that let the car "drive" while staying in place. The car is strapped down and connected to exhaust sampling equipment. Unlike the old NEDC test, the engine does not get a long warm-up period. The test starts with a cold engine, which is closer to how most Irish people start their car on a January morning.
The test runs through four distinct phases. First is the Low phase, which simulates stop-start city driving with a top speed of 56 km/h. This lasts about 10 minutes. Then comes Medium speed, reaching up to 76 km/h, representing suburban roads. The High phase goes to 97 km/h for rural road conditions. Finally, the Extra-High phase pushes the car up to 131 km/h, simulating motorway driving. The whole test takes around 30 minutes, compared to NEDC's 20 minutes.
During the test, the car runs through various speed profiles with accelerations, decelerations, and periods of steady speed. The driving patterns are based on actual data collected from real roads across Europe. Air conditioning can be switched on during the test if it is fitted as standard equipment. Larger wheels and tyres are also reflected in the result, which is why the same car model can have different WLTP figures depending on the spec.
The CO2 output is measured by analysing the exhaust gases collected during the test. This number, expressed in grams per kilometre, is what appears on the vehicle's certificate and what feeds into the Irish VRT calculation. Fuel consumption in litres per 100 km is also derived from this measurement. If you have ever wondered why the official fuel economy figure seems optimistic, it is because even WLTP is done under controlled laboratory conditions, not on the M50 in rush hour.
WLTP vs NEDC - Real World Differences
The difference between WLTP and NEDC figures is not just academic. It has a direct impact on how much VRT you pay. On average, WLTP CO2 figures are 10 to 25 percent higher than the NEDC figures for the same car. That jump can push a vehicle from one VRT band into a higher one, adding hundreds of euro to your bill.
Take a concrete example. A 2019 Volkswagen Golf 1.5 TSI petrol was rated at about 116 g/km under NEDC. Under WLTP, the same car comes in at roughly 138 g/km. That is a 19 percent increase. Under the old NEDC system, the car would sit in the 111 to 120 g/km VRT band at a 14 percent rate. Under WLTP, it moves into the 121 to 140 g/km band at 16 percent. On a car worth 25,000 euro, that difference works out to roughly 500 euro extra in VRT.
A diesel example makes the gap even clearer. A BMW 320d was rated at around 109 g/km under NEDC but comes in at 130 to 135 g/km under WLTP depending on trim. The diesel exhaust treatment systems that help cars pass real-world emissions tests add weight and slightly increase fuel consumption, which WLTP captures but NEDC did not.
Hybrids tend to show a smaller gap between the two tests, partly because their electric motor assistance helps at low speeds where both tests start. Plug-in hybrids can show larger discrepancies because the way the test weights electric-only driving versus petrol driving has changed. A PHEV that looked like it emitted 30 g/km under NEDC might register 50 to 70 g/km under WLTP, which notably affects its VRT band.
How to Find Your Vehicle's WLTP CO2 Figure
Finding the correct WLTP CO2 number for your car is the most important step before using the calculator. Use the wrong figure and your VRT estimate will be off. Here are the most reliable ways to find it.
The best source is the vehicle's certificate of conformity or type approval document. If you are buying from a dealer, they should have this. It lists the official CO2 emissions figure in g/km along with all the test details. For cars already registered in Ireland, the Vehicle Licensing Certificate (VLC) also shows the CO2 figure. You can request a copy of your VLC from Revenue's ROS system or through the motor tax office.
If you do not have the paperwork to hand, the manufacturer's website often lists WLTP figures for each model variant. Go to the specific model page, choose the exact engine and trim level you are looking at, and check the technical specifications. Be careful here. The figure for a 1.5 petrol with 16-inch wheels might be different from the same engine with 18-inch wheels. Optional extras like a panoramic sunroof or larger battery can also shift the number.
Online databases like the European Environment Agency's vehicle emissions portal or individual country transport authority websites can help. The UK's DVSA database is useful for cars originally sold in Britain. Just search for the make, model, and year. Some car review sites also publish WLTP figures in their specs sections, though you should always cross-reference with an official source if possible.
One common mistake is using the fuel consumption figure instead of the CO2 emissions number. They are related but not the same thing. The CO2 figure is measured in grams per kilometre and is the specific number you need for VRT. If all you can find is the litres per 100 km figure, you need to look harder. Revenue requires the g/km number.
WLTP VRT Impact - Real Examples
Here are three worked examples showing how WLTP CO2 figures affect VRT on actual cars you might consider importing into Ireland.
Example 1: 2022 Toyota Corolla Hybrid, valued at 24,000 euro. The WLTP CO2 figure for this car is 102 g/km. As a full hybrid, it qualifies for the hybrid VRT rate. At 102 g/km, it sits in the 101 to 120 g/km band, which carries a 12 percent rate. Being three years old, the age depreciation brings the OMSP to 90 percent of the market value, which is 21,600 euro. The VRT comes to 2,592 euro. Add the 500 euro registration and processing fees, and your total VRT cost is around 3,092 euro. Not bad for a reliable hybrid that sips fuel in Dublin traffic.
Example 2: 2021 BMW 320d xDrive, valued at 35,000 euro. Under WLTP, this diesel emits about 132 g/km. As a standard diesel (not a hybrid), it falls into the 121 to 140 g/km band at a 16 percent rate. After age depreciation for a four-year-old car, the OMSP drops to 75 percent of value, which is 26,250 euro. The VRT works out to 4,200 euro. That is a notable chunk on top of the purchase price, and it is exactly the kind of number that catches people off guard when they are used to the old NEDC figures.
Example 3: 2023 Volkswagen Tiguan 2.0 TDI, valued at 38,000 euro. This popular SUV has a WLTP CO2 rating of 158 g/km. At that level, it lands in the 156 to 170 g/km band with a 20 percent VRT rate. Two years old means the OMSP is 90 percent, or 34,200 euro. The VRT comes to 6,840 euro. Compare that to the NEDC figure of around 130 g/km which would have put it in a lower band at 16 percent, saving roughly 2,700 euro. This is why checking the WLTP number before you commit to a purchase is worth your time.
How WLTP Affects Your VRT Band
The WLTP CO2 figure directly determines which VRT band your vehicle falls into, and therefore what percentage rate is applied to the Open Market Selling Price. Under the Irish VRT system, vehicles with lower CO2 emissions pay a lower percentage rate. Because WLTP figures are typically 10-25% higher than the old NEDC ratings, the same car will often fall into a higher VRT band under WLTP, resulting in a higher tax bill at registration.
The practical impact varies depending on where your vehicle sits in the CO2 range. A car that was rated at 110 g/km under NEDC would have been in the 14% VRT band. Under WLTP, that same car might rate at 132 g/km, pushing it into the 16% band. On a vehicle worth €30,000, that 2% difference adds €600 to your VRT bill. For cars that cross multiple band thresholds, the impact can be even more notable. A diesel SUV that was 170 g/km NEDC might rate at 205 g/km under WLTP, moving from the 24% band to the 28% band.
Revenue applies the WLTP figure if one is available for your vehicle. If only an NEDC figure exists for an older car, Revenue will use that instead. The key point is that you should always check which test standard your car was certified under before using any VRT calculator or band table. Using the wrong figure can lead to an estimate that is thousands of euro off from the actual amount Revenue will charge.
WLTP VRT FAQs
What is the WLTP test and why does it matter for VRT?
WLTP stands for Worldwide Harmonised Light Vehicle Test Procedure. It is the current EU standard for measuring vehicle CO2 emissions and fuel consumption, and it replaced the older NEDC test. WLTP matters for VRT because your vehicle's CO2 figure directly determines which VRT band you fall into and what percentage rate you pay. The WLTP test lasts 30 minutes, covers four driving phases from urban stop-start to motorway speeds, and starts with a cold engine. It produces CO2 figures that are typically 10-25% higher than the old NEDC ratings for the same vehicle, meaning most cars pay more VRT under WLTP than they would have under NEDC.
How do I find my vehicle's WLTP CO2 figure?
Your vehicle's WLTP CO2 figure can be found on the Certificate of Conformity, which is the official document from the manufacturer listing all technical specifications. For cars already registered in Ireland, the Vehicle Licensing Certificate also shows the CO2 figure. If you do not have either document, check the manufacturer's website for the specific model variant and engine type. Online databases like the European Environment Agency's vehicle emissions portal can also help. Be careful to use the figure for your exact trim level and engine, because the same model with different wheel sizes, optional equipment, or transmission types can have different WLTP figures. A car with 18-inch wheels may have a higher CO2 figure than the same car with 16-inch wheels.
How much more VRT will I pay under WLTP compared to NEDC?
The amount depends on where your vehicle sits in the CO2 range and how much the WLTP figure exceeds the NEDC figure. On average, WLTP figures are 10-25% higher than NEDC, which typically pushes vehicles one or two VRT bands higher. For a car worth €25,000, moving from the 14% band to the 16% band adds €500 in VRT. Moving from 14% to 20% adds €1,500. For higher-value vehicles, the difference can be several thousand euro. The actual increase depends on how close your car's NEDC figure was to the band threshold and where the WLTP figure lands. Our calculator above gives you a precise estimate based on your specific WLTP CO2 figure and vehicle value.
Are all cars now tested under WLTP in Ireland?
All new cars registered in Ireland since September 2018 carry WLTP figures. This includes new cars sold by Irish dealers and new imports. However, used cars imported from abroad that were first registered before September 2018 may still carry NEDC figures. For cars from the transition period between September 2017 and August 2018, some vehicles have both NEDC and WLTP figures listed. In those cases, Revenue generally uses the test standard that was current at the time of the vehicle's original registration. You cannot choose the more favourable standard. If you are importing a used car, always check which test standard appears on the actual documentation rather than relying on advertised figures.
How does WLTP handle optional equipment?
Unlike the old NEDC test, which tested only a base variant of each model, WLTP accounts for optional equipment that affects the vehicle's weight and aerodynamics. Optional extras such as larger alloy wheels, panoramic sunroofs, roof rails, upgraded audio systems, and even different seat materials can affect the WLTP result. This means the same car model with different options packages can have different WLTP CO2 figures and therefore different VRT liabilities. When you are comparing vehicles or using our calculator, try to find the WLTP figure for the exact specification you are buying. A 2022 Volkswagen Golf with 16-inch wheels might have a WLTP figure of 128 g/km, while the same car with 18-inch wheels and a sunroof could be 135 g/km.
Does WLTP affect motor tax as well as VRT?
Yes, the WLTP CO2 figure also affects your annual motor tax in Ireland. The motor tax system uses CO2-based bands that are separate from VRT bands but also rely on the vehicle's emissions figure. For cars registered from 2021 onward, the motor tax system uses WLTP figures. For older cars, motor tax may still be calculated using NEDC figures. This means that if you import a used car with a WLTP figure, it will affect both your upfront VRT cost and your ongoing annual motor tax. The exact motor tax band depends on the CO2 figure, with lower-emission vehicles paying less. Because WLTP figures are higher than NEDC, your annual motor tax may also be higher than what the equivalent NEDC figure would have produced.
Is the WLTP test accurate for real-world driving?
WLTP is notably more accurate than the old NEDC test, but it is still a laboratory test conducted under controlled conditions. Real-world driving typically produces CO2 emissions that are 10-20% higher than the WLTP figure, due to factors such as traffic congestion, driving style, weather conditions, road gradients, and vehicle load. However, WLTP is much closer to reality than NEDC, which was commonly 30-40% optimistic. The test's four-phase structure, cold-start requirement, and inclusion of optional equipment all contribute to its improved accuracy. For VRT purposes, the official WLTP figure is what Revenue uses regardless of real-world variance. The figure on the certificate is the one that determines your tax band.