What is the difference between P11D value and on-the-road (OTR) price?

The OTR price includes the Government First Registration Fee and the first-year Vehicle Excise Duty (VED / road tax). The P11D value excludes both of these statutory fees, meaning P11D is slightly lower than the full OTR showroom price.

Does an employee pay National Insurance on a company car?

No. Employees do not pay Class 1 Employee National Insurance on non-cash benefits-in-kind. Only the employer pays Class 1A National Insurance (fixed at 15.0% in 2026/27) on the taxable BIK value.

How does HMRC collect company car tax?

HMRC collects company car tax by adjusting your PAYE tax code on your monthly payslip. The annual taxable BIK value is deducted from your Personal Allowance, causing your employer to withhold the extra income tax evenly across your 12 monthly paychecks.

Can I claim tax-free mileage when driving my company car for business?

If your employer does not pay for fuel, you can claim HMRC Advisory Fuel Rates (AFR) tax-free for business journeys. For electric company cars, you can claim the Advisory Electricity Rate (AER, 9p per mile).

What is the BIK rate for pure electric vehicles in 2026/27?

For the 2026/27 tax year, the Benefit-in-Kind (BIK) rate for pure zero-emission electric vehicles (0g/km CO2) is 3% of the P11D list price.

How does the free private fuel benefit multiplier work?

If your employer pays for fuel used on private journeys, HMRC applies a statutory multiplier of £28,200 for 2026/27. The taxable fuel benefit is £28,200 multiplied by your car’s BIK percentage, taxed at your marginal income tax rate.

How to Calculate Company Car Fuel Benefit (HMRC Rules)

Published: August 2026 | Fact-Checked & Audited By: Tax Calculators for UK Editorial Team (Chartered Tax Advisor & Accountant)

This guide is fully updated for the 2026/27 HMRC tax year. All calculations and tax rules have been audited against official UK legislation and statutory guidance.

Many UK employers offer to pay for all fuel used in a company car, including fuel consumed for private travel, weekend trips, and holidays. While “free fuel” sounds like an excellent employment perk, it is treated as a taxable benefit by HM Revenue & Customs (HMRC). In many instances, the tax you pay on the fuel benefit exceeds the actual value of the fuel you consume. This comprehensive guide details the HMRC fuel benefit calculation, shows you how to determine your break-even point, and explains how to opt-out to save money.

1. The Fuel Benefit Multiplier Formula

HMRC does not calculate your tax based on the actual quantity of fuel you consume. Instead, they use a flat-rate multiplier that is adjusted annually. The taxable value of the fuel benefit is calculated as follows:

Taxable Fuel Benefit = HMRC Fuel Multiplier × Car’s BIK percentage band

For the 2026/27 tax year, the fuel multiplier is set at £27,800. This multiplier applies to all petrol, diesel, and hybrid cars, regardless of engine size. Once the taxable value is determined, it is multiplied by your personal income tax rate (20%, 40%, or 45%) to find the tax payable.

2. Electric Vehicle Exception: Zero Fuel Benefit for EVs

If you drive a pure electric company vehicle, there is no fuel benefit charge. Because electricity is not classified as “fuel” under HMRC’s statutory definition, employers can pay for all electricity consumed by an electric company car without triggering any fuel benefit tax liability. This includes paying for home electricity reimbursements or workplace charging.

3. How to Opt-Out and Stop Paying Fuel Benefit Tax

If you calculate that the fuel benefit is costing you money, you can opt-out at any time. To do this, you must notify your employer that you want to stop receiving free private fuel. You must then pay for all private fuel out of your own pocket. If your employer provides a company fuel card, you must reimburse them for all private miles driven using HMRC’s Advisory Fuel Rates (AFR).

4. Step-by-Step Mathematical Calculation

Let’s calculate the fuel benefit tax for a higher-rate (40%) taxpayer driving a petrol car with a 24% BIK band, and find their break-even mileage:

Retrieve Multiplier: £27,800.
Calculate Taxable Value: £27,800 × 24% = £6,672 BIK value.
Apply Tax Rate (40%): £6,672 × 40% = £2,668.80 annual tax.
Monthly Cost: £2,668.80 / 12 = £222.40.
Determine Break-Even Mileage: Assuming fuel costs £1.50 per liter (£6.82 per gallon) and the car averages 40 MPG:
- Cost per mile = £6.82 / 40 miles = 17.05p per mile.
- Break-even private miles = £2,668.80 / 0.1705 = **15,653 miles per year**.
Conclusion: If this employee drives fewer than 15,653 private miles a year, they are paying more tax than the fuel is worth. They should opt out immediately.

5. Frequently Asked Questions (FAQs)

Q1: Does my commute count as business mileage?
A: No. HMRC classifies travel between your home and your regular workplace as private travel. Commuting fuel is taxable under the fuel benefit charge.

Q2: What happens if I opt-out mid-year?
A: HMRC will calculate the fuel benefit charge pro-rata for the part of the year you received free fuel. However, if you opt-out, you must not receive free fuel again during the same tax year.

Q3: How is electricity treated for company vans?
A: Electricity is not fuel under HMRC rules, meaning electric vans also pay £0 fuel benefit! Check out our Company Car BIK Calculator.

Q4: Do Advisory Fuel Rates (AFR) include VAT?
A: Yes, AFR rates are VAT-inclusive rates published quarterly by HMRC.

Q5: Can I reclaim VAT on fuel for a private car?
A: Yes, but only for the portion used for business mileage, backed by detailed receipts.

Q6: What is the hybrid car fuel multiplier?
A: Hybrids pay the same standard £27,800 fuel benefit multiplier as standard combustion cars.

Q7: What if I reimburse my employer for private fuel?
A: If you reimburse the full cost of all private fuel before the end of the tax year, the fuel benefit charge is reduced to zero.

Q8: Does the employer pay NI on fuel benefit?
A: Yes, employers pay 13.8% Class 1A NI on the taxable fuel benefit value.

Calculate Company Car & Vehicle Tax

Put the figures from this guide into practice with our free, HMRC-audited interactive calculation tools:

Company Car Benefit-in-Kind (BIK) Calculator → Compare 2% EV rates against petrol/diesel P11D tax deductions. Salary Sacrifice & EV Car Calculator → Calculate National Insurance and Income Tax savings on vehicle salary sacrifice.