OMSP and Vehicle Registration Tax in Ireland: Why Revenue Ignores Your Purchase Price

The Open Market Selling Price (OMSP) is the value that Revenue assigns to a vehicle on the Irish retail market. It serves as the tax base for calculating Vehicle Registration Tax (VRT) and is often different from the price you actually paid for your car — particularly if you purchased it in the UK or abroad.

Whether you are importing a used vehicle, registering a new car, or simply trying to understand your VRT amount, this guide covers everything you need to know about how Revenue determines the OMSP, how it feeds into your VRT charge, and what options are available if you believe the figure is incorrect.

In Brief

• OMSP (Open Market Selling Price) is Revenue's assessed retail value of a vehicle on the Irish market — it is the tax base used to calculate your VRT, and it often differs from the price you actually paid abroad.
• VRT is calculated by applying a CO₂-based percentage (7% to 41% for cars) to the OMSP, plus a separate NOx levy — the higher your emissions and OMSP, the more you pay.
• Revenue determines the OMSP using Irish dealer prices, trade guides, vehicle age, mileage, and condition — not your purchase price, which is why UK imports often attract a higher valuation than expected.
• You can appeal an OMSP assessment within 30 days if you have evidence that Revenue's valuation is too high, such as comparable Irish market listings or an independent professional appraisal.

What Does OMSP Stand For?

OMSP stands for Open Market Selling Price. In practice, it represents the price at which Revenue believes your vehicle would sell on the Irish market — not what you paid for it, and not its trade-in value. Revenue uses the OMSP as the valuation baseline on which the percentage of VRT is applied.

This is a critical distinction: two identical cars purchased at different prices abroad can still receive the same OMSP once they arrive in Ireland, because Revenue's assessment is based on comparable Irish retail data rather than on the individual transaction.

OMSP vs Purchase Price: Why the Figures Differ

If you bought a car in the UK for £12,000, you might expect the Irish tax to reflect that amount. In most cases, however, Revenue will assign a higher value — for example, €18,500 — because Irish retail prices for the same make and model tend to be higher than those in Britain.

The logic is straightforward: the OMSP reflects what a buyer in Ireland would set aside to purchase the same vehicle from an Irish dealer, including any extras or specification differences that affect local market pricing. Your personal bargain abroad does not reduce the chargeable amount.

OMSP vs OMV: Are They the Same?

This is one of the most common points of confusion. OMV (Open Market Value) typically refers to the pre-registration list price of a vehicle — the sticker price before any grants, reliefs, or negotiations are applied. OMSP, on the other hand, is Revenue's assessed retail price on the secondary or current Irish market.

In the case of electric vehicles, both figures matter: the OMV determines whether the car qualifies for VRT relief, while the OMSP is still the basis for the core VRT rates.

How Revenue Determines the OMSP

Revenue does not simply pick a number. The process relies on several data links and market indicators:

1. Irish dealership prices and classified ads. Revenue checks platforms such as DoneDeal.ie, Carzone.ie, and CompleteCar.ie to see what comparable vehicles are listed for on the Irish market.

2. UK and Irish trade guides. Industry-standard information sources used by motor dealers help Revenue cross-reference wholesale and retail pricing.

3. Age and depreciation. Older vehicles are subject to reduced valuations. Revenue assumes average monthly mileage of 2,100 km for diesel vehicles and 1,500 km for all other fuel types. Significantly higher mileage can bring the OMSP down.

4. Condition rating. For VRT purposes, vehicles may be rated as good, fair, or poor. Most are assessed as good, but documented mechanical or cosmetic issues can lower the figure.

5. Model availability. Rare or uncommon models — including motor caravans, classic cars, and certain prestige marques — require individual research by Revenue staff. In such a case, the standard VRT calculator cannot provide an estimate, and the OMSP is only finalised after the vehicle is presented at an NCTS centre for inspection.

How the OMSP Feeds Into Your VRT Calculation

Once Revenue has established the OMSP, the VRT charge is calculated using a formula that combines two components: the CO₂-based percentage and the NOx charge.

The formula: VRT = (CO₂ rate × OMSP) + NOx levy

VRT Categories at a Glance

Revenue must first determine which VRT category applies to your vehicle before the tax becomes payable:

Category A covers passenger cars, SUVs, and minibuses that can carry no more than eight people plus a driver. The CO₂ percentage ranges from 7% to 41% of the OMSP, depending on the emissions band. This category also included certain N1 vehicles with four or more seats.

Category B vehicles are commercial vehicles designed and constructed for the carriage of goods, weighing no more than 3.5 tonnes. Since July 2025, the VRT rates are based on CO₂ emissions: 8% of OMSP for vehicles up to 120 g/km, and 13.3% for those above. Some qualifying vans pay a flat VRT charge of just €200 if they meet specific weight-to-mass ratios. Motor caravans also fall under this category.

Category C applies to larger commercial vehicles, agricultural tractors, buses, and vehicles over 30 years old. The VRT charge is a flat €200.

Category D vehicles — such as fire engines, refuse carts, and road construction transport — are not subject to VRT at all.

Category M covers motorcycles and e-mopeds. The VRT charge is based on engine cubic capacity: €2 per cc up to 350, and €1 per cc thereafter. A motorcycle over 30 years old is fully exempt. Series production electric motorcycles, including e-mopeds, are also exempt from VRT until 31 December 2026.

Understanding NOx Emissions and the Levy

In addition to the CO₂ component, most Category A and some Category B vehicles face an additional NOx charge based on their NOx emissions. This levy is calculated separately and then added to the CO₂-based figure to produce the final VRT amount.

The NOx charge is particularly significant for older diesel vehicles and certain petrol models with higher nitrogen oxide output. A hybrid vehicle with low NOx output will typically face a smaller levy, which can meaningfully reduce the overall bill.

Worked Example

Suppose you are importing a 2022 petrol car from the UK with 125 g/km CO₂ and an OMSP of €22,000:

Step 1 — The CO₂ band of 125 g/km falls into the 16.75% bracket. Step 2 — CO₂ component = 16.75% × €22,000 = €3,685. Step 3 — The NOx charge for this vehicle is, say, €268 (exact amount depends on the vehicle's specific NOx output in mg/km). Step 4 — Total VRT = €3,685 + €268 = €3,953.

This example shows how even a modest shift in the OMSP — say €1,000 higher — would increase the VRT amount by roughly €168 in this emissions band.

How to Research Your Vehicle's OMSP Before You Buy

Rather than waiting for a surprise at the NCTS centre, you can estimate the likely OMSP yourself before committing to a purchase:

Step 1 — Search DoneDeal.ie and Carzone.ie for 5–10 comparable vehicles matching your make, model, year, engine size, and trim level.

Step 2 — Note the asking prices, then adjust downward slightly — advertised figures tend to be higher than actual transaction prices.

Step 3 — Check Revenue's official VRT calculator on ROS.ie. Enter the statistical code or vehicle details to see if your model is listed. The calculator covers over 25,000 valuations and will estimate the VRT due on the registration date.

Step 4 — For models not on the calculator, Revenue will only determine the OMSP after the vehicle is presented for registration. In this case, you may use the VRT Estimate Form to prepare your own pre-purchase assessment.

Step 5 — Factor in VAT (23% for most GB imports) and customs duty (10%) on top of the VRT to get a realistic total import cost.

How to Appeal an OMSP Assessment

If you believe Revenue's valuation is too high, you have the right to appeal within 30 days of the assessment date. To build a strong case, you will need:

Evidence of comparable sales — screenshots or printouts from Irish classifieds showing similar vehicles at lower prices.

A professional valuation — an independent assessment from a recognised motor dealer or valuer can carry significant weight.

Documentation of condition issues — if your vehicle has mechanical problems, accident history, or abnormal wear, provide inspection reports or repair estimates.

Revenue will review the evidence and may adjust the OMSP accordingly. If the appeal is successful, the VRT charge is recalculated and the difference refunded.

Common Mistakes When Dealing With OMSP

Using asking prices as gospel. Sellers often set prices higher than what they will accept. Revenue acknowledges this and adjusts accordingly, but your own research should do the same.

Confusing miles with kilometres. If your mileage figure is recorded in miles, convert it before comparing with Irish market data. A quick means of conversion: multiply miles by 1.609.

Ignoring specification differences. Engine size, transmission type, and trim level all affect the OMSP. A 1.6-litre diesel differs significantly in value from a 2.0-litre petrol of the same model.

Assuming the calculator is final. The ROS VRT calculator provides an estimate only. Revenue calculate the exact VRT due when the vehicle is presented at an NCTS centre for inspection and registration.

WLTP vs NEDC: Which CO₂ Figure Applies?

All new Category A and Category B vehicles use WLTP (Worldwide Harmonised Light Vehicle Test Procedure) data for their VRT calculation. However, some used vehicles were originally tested under the older NEDC standard.

For these vehicles, Revenue applies a conversion formula to produce an equivalent CO₂ figure:

• For diesel vehicles (Cat A): (NEDC CO₂ × 1.1405) + 12.858
• For other vehicles (Cat A): (NEDC CO₂ × 0.9227) + 34.554
• For diesel vehicles (Cat B): (NEDC CO₂ × 0.9498) + 41.539
• For other vehicles (Cat B): (NEDC CO₂ × 1.0105) + 18.335

The converted figure is then used to assign the appropriate CO₂ tax band. This means that a used import with only an NEDC rating is not disadvantaged — but the converted number may place it in a higher band than you might expect.

Frequently Asked Questions

What does OMSP stand for?

OMSP stands for Open Market Selling Price. It is the retail value Revenue assigns to a vehicle in Ireland and forms the basis for your VRT calculation.

Is OMSP the same as OMV?

No. OMV refers to the pre-registration list price, while the OMSP reflects the current assessed Irish market value. Both are relevant in different contexts, but only the OMSP is used to calculate the core VRT.

Why is the OMSP higher than what I paid?

Irish retail prices are typically higher than those in the UK or elsewhere. Revenue bases the OMSP on Irish market data — not on what you personally paid abroad.

Can I appeal my OMSP?

Yes. You have 30 days from the assessment date to submit evidence that the valuation should be reduced. Professional appraisals and Irish market comparables are the strongest options.

Does mileage affect the OMSP?

Yes. Vehicles with significantly higher mileage than the average — 2,100 km/month for diesel, 1,500 km/month for others — may receive a lower OMSP, which reduces the VRT charge.

How is VRT calculated for electric and hybrid cars?

Electric and hybrid vehicles follow the same CO₂-based formula, but with lower emissions they fall into lower VRT rates. Fully electric cars with an OMSP up to €40,000 may qualify for relief of up to €5,000. Those between €40,000 and €50,000 receive a reduced level of relief, while vehicles above €50,000 no longer qualify. These reliefs apply to vehicles registered before 31 December 2026.

What if my vehicle is not on the VRT calculator?

Revenue will assess it individually after it is presented at an NCTS centre. For uncommon models, this process may involve expert consultation and take additional time.

How are VRT and NOx calculated together?

The CO₂ percentage is applied to the OMSP to produce the main VRT component. The NOx charge is calculated separately based on the vehicle's nitrogen oxide output, then both figures are added together to produce the total VRT due.