The calculator
About this tool
The taxable benefit on a company car is based on the CO₂ emissions of the car. These calculations are for the 2026/27 tax year.
Enter the list price, CO₂ emissions, whether the employer provides fuel for private use and your marginal income-tax rate. The calculator returns the cash equivalent of the benefit, the annual tax cost and the monthly figure.
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How the company car tax calculator works
A company car available for private use is a taxable benefit in kind. The taxable amount is based on the car’s list price multiplied by an “appropriate percentage” set by its CO₂ emissions (with the lowest percentages for electric and low-emission cars), then taxed at your income tax rate. For plug-in hybrids emitting 1–50 g/km the percentage also depends on the car’s pure-electric range, and diesels that do not meet the RDE2 standard carry a 4% supplement, up to the 37% maximum. Where private fuel is also provided, a separate fuel benefit applies.
This calculator estimates the benefit-in-kind and the tax on it using HMRC’s published appropriate percentages for the tax year you choose. The bands rise each year, so the result is a guide — we can advise on the most tax-efficient vehicle choice for you or your business.
Emissions decide the bill, not price
The taxable benefit is a percentage of the list price, and the percentage comes from CO₂ emissions. That is why two cars costing the same can produce very different tax, and why a fully electric car sits at a small fraction of the percentage applied to a petrol equivalent. For anyone choosing a company car, the emissions figure matters more than the price.
The employer pays Class 1A National Insurance on the same benefit, so the choice affects both sides.
Free private fuel is usually the worst deal available
The fuel benefit is calculated from a fixed figure regardless of how much fuel you actually use privately. Unless private mileage is genuinely high, the tax on the benefit commonly exceeds the cost of the fuel itself — paying for your own private fuel is frequently cheaper. It is worth calculating rather than accepting as a perk.
Frequently asked
Are electric company cars taxed less?
Yes — fully electric cars attract a very low appropriate percentage, making them highly tax-efficient as a company car compared with petrol or diesel equivalents.
Should I provide private fuel?
The fuel benefit charge is often more than the fuel is worth for lower-mileage drivers. We can model whether providing private fuel makes sense in your case.
Why is an electric company car taxed so lightly?
Because the benefit is a percentage of list price set by CO₂ emissions, and an electric car sits at a small fraction of the percentage applied to a petrol equivalent. The same list price produces very different tax for the employee and different Class 1A for the employer.
Should I take the free fuel?
Usually not. It is taxed on a fixed figure regardless of your actual private mileage, so unless that mileage is high the tax often exceeds what the fuel is worth. Run both before accepting it.
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