Do diesel cars pay more road tax than petrol cars?

Yes. From year 2 onwards, diesel cars pay GBP 190/year compared to GBP 180/year for petrol cars. This GBP 10 difference is the diesel supplement. In year 1, diesel cars with equivalent CO2 emissions pay the same as petrol — the diesel supplement only applies from year 2. However, diesel cars typically have higher CO2 emissions than equivalent petrol cars, placing them in higher VED bands.

What is the diesel road tax surcharge?

The diesel road tax surcharge is GBP 10/year, applied to all diesel vehicles (except hybrid diesels) from year 2 of registration. This brings the standard rate from GBP 180/year (petrol) to GBP 190/year (diesel). It was introduced to reflect the higher NOx emissions from diesel vehicles compared to petrol. There is no first-year diesel surcharge — only the annual supplement from year 2.

Is it worth buying a diesel car in 2026?

For most drivers, a diesel car is no longer worth buying purely for financial reasons. The diesel supplement (GBP 10/year), higher purchase prices, and declining fuel savings from improved petrol efficiency mean diesel rarely pays back. Diesel makes sense for high-mileage drivers (30,000+ miles/year), motorway drivers, and those who regularly tow heavy loads — where fuel economy advantages outweigh the tax and purchase price premiums.

How much road tax does a diesel SUV pay?

A typical diesel SUV with CO2 emissions of 160-180g/km falls into Bands G-I. First-year rates range from GBP 285-445. From year 2, the diesel supplement applies: GBP 180 + GBP 10 = GBP 190/year. Over 5 years, a diesel SUV typically costs GBP 1,000-1,600 in road tax. A petrol equivalent with lower CO2 emissions would cost GBP 180-200 less over the same period.

Do diesel company cars pay extra tax?

Diesel company cars do not pay extra VED, but they do attract higher benefit-in-kind rates. A diesel car with 120-130g/km CO2 attracts a BiK rate of 35%, compared to 21-24% for an equivalent petrol. For a higher-rate taxpayer with a GBP 40,000 diesel company car, this means GBP 5,600/year in BiK tax vs GBP 3,600/year for the petrol equivalent — a GBP 2,000/year difference.

UK Road Tax Diesel Cars 2026 — Diesel VED Rates and Surch...

UK Road Tax Diesel Cars 2026

Diesel cars have long been popular for their fuel economy, but the road tax treatment of diesel vehicles has become less favourable. Understanding the diesel supplement and current rates helps you decide whether diesel makes financial sense in 2026. ITV.es and DGT.

Diesel Road Tax Basics

The Diesel Supplement

From year 2 of registration onwards, all diesel vehicles pay an extra £10/year on top of the standard rate:

| Vehicle Type | Year 1 Rate | Years 2+ Rate |

|-------------|-------------|----------------|

| Petrol | Standard first-year | £180 |

| Diesel | Standard first-year | £190 |

| Electric | £0 | £180 |

| Hybrid | Based on CO2 | £180 |

The £10/year diesel supplement reflects the higher NOx emissions from diesel vehicles compared to petrol equivalents.

First-Year Diesel Rates

Diesel first-year rates are based on CO2 emissions, identical to petrol vehicles:

| CO2 Band | First Year Rate |

|---------|----------------|

| 0g/km (Band A) | £0 |

| 1-50g/km (Band B) | £0-30 |

| 51-75g/km (Band C) | £15-30 |

| 76-90g/km (Band D) | £120 |

| 91-100g/km (Band E) | £130 |

| 101-110g/km (Band F) | £145 |

| 111-120g/km (Band G) | £160 |

| 121-130g/km (Band G) | £195 |

| 131-150g/km (Band H) | £215-335 |

| 151-165g/km (Band I) | £285-335 |

| 166-175g/km (Band I) | £285-335 |

| 176-200g/km (Band J) | £375-435 |

| 201-225g/km (Band K) | £495-520 |

| 226-255g/km (Band L) | £545-570 |

| Over 255g/km (Band M) | £590+ |

Diesel vs Petrol Road Tax

Annual Road Tax Comparison

|-------------|-----|--------|----------|--------------|

| Small petrol hatchback | 110g/km | £145 | £180 | £865 |

| Small diesel hatchback | 105g/km | £130 | £190 | £790 |

| Family petrol SUV | 155g/km | £285 | £180 | £1,005 |

| Family diesel SUV | 150g/km | £285 | £190 | £1,015 |

| Large diesel SUV | 185g/km | £435 | £190 | £1,195 |

| Premium diesel saloon | 165g/km | £285 | £190 | £1,015 |

For equivalent vehicles, the diesel supplement adds £50 over 5 years — a modest amount.

The real cost difference comes from CO2 emissions, not the fuel type. A diesel with similar CO2 to a petrol pays only £10/year more.

Diesel First-Year Rate Examples

Common Diesel Cars

|---------|-----|-----------|----------|--------------|

| VW Golf 2.0 TDI | 115g/km | £160 | £190 | £910 |

| Skoda Octavia 2.0 TDI | 112g/km | £160 | £190 | £910 |

| Ford Focus 1.5 TDCI | 99g/km | £130 | £190 | £850 |

| BMW 320d | 118g/km | £160 | £190 | £910 |

| Mercedes C220d | 124g/km | £195 | £190 | £955 |

| Audi A4 35 TDI | 122g/km | £195 | £190 | £955 |

Premium Diesel Vehicles (Over GBP 40,000)

|---------|-----|-----------|-----------|----------|

| BMW 520d | 125g/km | £195 | £590 | £190 |

| Mercedes E220d | 128g/km | £195 | £590 | £190 |

| Audi A6 40 TDI | 132g/km | £215 | £590 | £190 |

| Range Rover Sport 3.0 SD | 198g/km | £445 | £590 | £190 |

Diesel Supplement Impact

Over 5 Years

The diesel supplement adds £50 over 5 years vs petrol. Compared to the higher purchase price of diesel vehicles (typically £1,500-3,000 more), the fuel economy must offset this premium and the supplement.

Typical diesel fuel economy advantage: 5-8 MPG vs equivalent petrol

At 12,000 miles/year and GBP 1.50/litre: GBP 200-300/year fuel saving
Over 5 years: GBP 1,000-1,500 fuel saving
Road tax supplement: GBP 50 over 5 years

Diesel pays back if you drive enough miles to recover the purchase price premium through fuel savings.

Diesel Company Car Tax

Benefit-in-Kind for Diesel

Diesel BiK rates are based on CO2 emissions, the same as petrol. However, diesel cars typically emit more CO2 than petrol equivalents:

| CO2 Band | BiK Rate | £40k Car Employee Tax |

|---------|----------|--------------------------|

| 120-130g/km | 35% | £5,600/year |

| 131-140g/km | 36% | £5,760/year |

| 141-150g/km | 37% | £5,920/year |

Compare to petrol equivalent at 120g/km: 21% BiK = £3,360/year.

Diesel company car costs £2,240/year more in BiK tax than the petrol equivalent.

When Diesel Makes Sense in 2026

Diesel Is Worth It If:

High annual mileage: 25,000-30,000+ miles/year means fuel savings recover the premium
Motorway driving: Diesel engines are most efficient at constant high speeds
Towing: Diesel torque is superior for caravans and trailers
Taxi or business use: BiK rates based on CO2, not fuel type — diesel irrelevant

Diesel Is Not Worth It If:

Low annual mileage: Under 10,000 miles/year
Urban driving: Short trips prevent diesel reaching operating temperature
Company car: Higher BiK rates for higher CO2 vehicles
Environmental concerns: Diesel has higher NOx and particulate emissions

Key Takeaways

1. Diesel supplement adds £10/year from year 2 — modest additional cost

2. First-year rates are based on CO2 — same as petrol for equivalent emissions

3. Real cost difference comes from CO2 band, not fuel type

4. Premium diesel (£40,000+) pays £410/year supplement for years 2-6

5. Company car diesel costs more in BiK due to higher typical CO2

6. Fuel savings of £200-300/year can offset the purchase price premium

7. High-mileage drivers benefit most from diesel fuel economy

8. For most buyers, a petrol or hybrid is more cost-effective in 2026

Diesel cars pay modestly more road tax than petrol equivalents, but the supplement is small. The bigger financial question is whether your driving patterns justify the higher purchase price through fuel savings.

Official Resources: ITV.es - ITV Booking | DGT - Direccion General de Trafico