If your company pays for all your fuel used by your company car and you do not identify and pay back the personal mileage element, then there is a taxable fuel benefit as well as your car benefit.
Calculation Example
The car fuel benefit is based on a set figure £24,600 for 2021/22 (2022/23 £25,300) x benefit in kind percentage for your company car. To calculate the benefit in kind percentage you need to consider whether your car was first registered before 6th April 2020 or after- as there are different tables for each ( see below).
Company car benefit-in-kind tax rates for cars first registered before April 6, 2020
| % of P11D price | 2021/22 CO2 g/km/(electric mileage range) | 2022/23 CO2 g/km/(electric mileage range) |
| 0 | N/A | N/A |
| 1 | 0 | N/A |
| 2 | 1-50 (up to 130 miles | 0-50 (up to 130 miles |
| 5 | 1-50 (70-129 miles) | 1-50 (70-129 miles) |
| 8 | 1-50 (40-69 miles) | 1-50 (40-69 miles) |
| 12 | 1-50 (30-39 miles) | 1-50 (30-39 miles) |
| 14 | 1-50 (under 30 miles) | 1-50 (under 30 miles) |
| 15 | 51-54 | 51-54 |
| 16 | 55-59 | 55-59 |
| 17 | 60-64 | 60-64 |
| 18 | 65-69 | 65-69 |
| 19 | 70-74 | 70-74 |
| 20 | 75-79 | 75-79 |
| 21 | 80-84 | 80-84 |
| 22 | 85-89 | 85-89 |
| 23 | 90-94 | 90-94 |
| 24 | 95-99 | 95-99 |
| 25 | 100-104 | 100-104 |
| 26 | 105-109 | 105-109 |
| 27 | 110-114 | 110-114 |
| 28 | 115-119 | 115-119 |
| 29 | 120-124 | 120-124 |
| 30 | 125-129 | 125-129 |
| 31 | 130-134 | 130-134 |
| 32 | 135-139 | 135-139 |
| 33 | 140-144 | 140-144 |
| 34 | 145-149 | 145-149 |
| 35 | 150-154 | 150-154 |
| 36 | 155-159 | 155-159 |
| 37 | 160+ | 160+ |
For each tax year add 4% for diesel cars up to a maximum of 37%. Cars that meet the Real Driving Emissions Step 2 (RDE2) standard are exempt.
Company car benefit-in-kind tax rates for cars first registered from April 6, 2020
| % of P11D price | 2021/22 CO2 g/km/(electric mileage range) | 2022/23 CO2 g/km/(electric mileage range) |
| 0 | N/A | N/A |
| 1 | 0-50 (up to 130 miles | N/A |
| 2 | N/A | 0-50 (up to 130 miles |
| 3 | N/A | N/A |
| 4 | 1-50 (70-129 miles) | N/A |
| 5 | N/A | 1-50 (70-129 miles) |
| 6 | N/A | N/A |
| 7 | 1-50 (40-69 miles) | N/A |
| 8 | N/A | 1-50 (40-69 miles) |
| 10 | N/A | N/A |
| 11 | 1-50 (30-39 miles) | N/A |
| 12 | N/A | 1-50 (30-39 miles) |
| 13 | 1-50 (under 30 miles) | N/A |
| 14 | 51-54 | 1-50 (under 30 miles) |
| 15 | 55-59 | 51-54 |
| 16 | 60-64 | 55-59 |
| 17 | 65-69 | 60-64 |
| 18 | 70-74 | 65-69 |
| 19 | 75-79 | 70-74 |
| 20 | 80-84 | 75-79 |
| 21 | 85-89 | 80-84 |
| 22 | 90-94 | 85-89 |
| 23 | 95-99 | 90-94 |
| 24 | 100-104 | 95-99 |
| 25 | 105-109 | 100-104 |
| 26 | 110-114 | 105-109 |
| 27 | 115-119 | 110-114 |
| 28 | 120-124 | 115-119 |
| 29 | 125-129 | 120-124 |
| 30 | 130-134 | 125-129 |
| 31 | 135-139 | 130-134 |
| 32 | 140-144 | 135-139 |
| 33 | 145-149 | 140-144 |
| 34 | 150-154 | 145-149 |
| 35 | 155-159 | 150-154 |
| 36 | 160-164 | 155-159 |
| 37 | 165+ | 160+ |
For each tax year add 4% for diesel cars up to a maximum of 37%. Cars that meet the Real Driving Emissions Step 2 (RDE2) standard are exempt.
So in this example the car fuel benefit is £25,300 x 27% ( if in 2022/23 your CO2 emissions were 110 CO2 g/km) = £6,831 taxable benefit.
Therefore the director will pay personal tax on this amount, if he is higher rate tax payer, this will be £6,831 x 40% = £2,732.40.
Best practice is for the director to ONLY claim his business mileage if he wishes to avoid this taxable benefit.