P11D Reporting for Company Cars: A Practical Guide for Employers

Company car tax benefit in kind 2026 is reported to HMRC on form P11D, which records the taxable value of the car so the employee pays income tax on it and the company pays Class 1A National Insurance. When a limited company provides a car that is available for private use, HMRC treats that car as a taxable benefit rather than a tax-free perk. The taxable amount is calculated from the car's list price and its CO2 emissions, and the figure must reach HMRC accurately and on time to avoid penalties. Blue Tick Accountants, a Guildford-based UK tax advisory and accountancy practice, helps directors and employers get these numbers right and decide whether a company car is worth offering at all.

This guide explains how the benefit in kind is calculated, the electric car benefit in kind UK rates for 2026/27, how P11D reporting works in practice, and whether paying a car allowance instead is more tax efficient.

Key Takeaways

• Company car tax benefit in kind 2026 is calculated as the car's list price multiplied by an appropriate percentage set by its CO2 emissions, then taxed at the employee's marginal income tax rate.
• Fully electric cars carry a 4% BIK appropriate percentage in the 2026/27 tax year, rising by one percentage point a year to 5% in 2027/28.
• The company car benefit is reported on form P11D, which must reach HMRC by 6 July following the end of the tax year on 5 April.
• Employers pay Class 1A National Insurance at 15% on the taxable value of the company car for the 2026/27 tax year.
• A petrol or diesel car can attract a BIK appropriate percentage of up to 37%, making high-emission cars an expensive benefit.
• A cash car allowance is treated as normal salary, subject to income tax and National Insurance, and can be cheaper than a high-emission company car but rarely beats an electric one.

How is company car benefit in kind calculated in 2026/27?

The taxable benefit of a company car equals the car's list price multiplied by an appropriate percentage based on CO2 emissions, and the employee then pays income tax on that figure at their marginal rate. The list price is the manufacturer's published price when the car was first registered, including VAT, delivery and most optional extras, not the price the company actually paid. This is often called the P11D value.

The appropriate percentage rises with emissions. A zero-emission electric car sits at the bottom of the scale, while a high-emission petrol or diesel car can reach the 37% ceiling. Once you have the taxable benefit, the tax the employee pays depends on their income tax band: 20%, 40% or 45%.

Consider a petrol car with a list price of £30,000 and an appropriate percentage of 30%. The taxable benefit is £9,000. A higher-rate taxpayer at 40% pays £3,600 in income tax on the car each year. The company separately pays Class 1A National Insurance at 15% on the same £9,000, adding £1,350 to the employer's cost.

What is the electric car benefit in kind UK rate for 2026/27?

Fully electric cars carry a benefit in kind appropriate percentage of 4% in the 2026/27 tax year. Electric vehicles remain by far the most tax-efficient company car because the appropriate percentage is a fraction of what a comparable petrol or diesel model attracts. The rate has been climbing gradually from 2% and reaches 5% in 2027/28, but even at these levels the electric car benefit in kind UK charge stays low.

Take an electric car with a list price of £45,000. At the 4% rate the taxable benefit is £1,800. A higher-rate taxpayer at 40% pays just £720 in income tax for the year, and the company pays Class 1A National Insurance of £270 at 15%. Compare that with the £3,600 income tax on the petrol example above and the appeal is clear.

The BIK company car savings are what make salary-sacrifice electric car schemes attractive to both directors and staff. Because the taxable benefit is so small, an electric company car can cost an employee only a few hundred pounds a year in tax while removing the running costs from their own pocket.

Directors should weigh the benefit charge against simply taking the cash instead, a comparison our guide to how directors pay themselves sets out.

How does P11D reporting work for company cars?

Form P11D reports the taxable value of every company car and other benefits to HMRC after the tax year ends on 5 April. Employers must submit a P11D for each employee who had a company car available for private use, and a P11D(b) summarising the total Class 1A National Insurance due. Both forms must reach HMRC by 6 July following the end of the tax year, and the Class 1A National Insurance must be paid by 22 July if paying electronically.

The P11D shows the car's list price, the appropriate percentage, any periods the car was unavailable, and any capital contribution the employee made. Getting the list price wrong, or forgetting optional extras, is the most common error and can trigger an HMRC correction.

Late or incorrect P11D filing carries penalties. A late P11D(b) attracts a penalty of £100 per 50 employees for each month or part month it is outstanding, and inaccurate returns can lead to further penalties. Many employers now payroll benefits in kind instead, reporting the value through the payroll in real time, which removes the need for a P11D for those benefits. Payrolling of most benefits becomes mandatory for employers in the coming years, so it is worth preparing early.

Is a car allowance more tax efficient than a company car?

A cash car allowance is often more tax efficient than a high-emission company car but rarely beats an electric one, because the allowance is taxed as ordinary salary while an electric company car is taxed on a tiny benefit figure. A car allowance is added to the employee's pay, subject to income tax and employee National Insurance, and the employer pays employer National Insurance on it too. The employee then buys or leases their own car and can claim mileage using HMRC approved rates.

For a petrol or diesel driver, the allowance can work out cheaper than being taxed on a 30% or higher appropriate percentage. For an electric driver, the 4% benefit in 2026/27 usually makes the company car the clear winner. The right answer depends on the car chosen, the employee's tax band, and how many business miles they drive.

There is no single correct choice. A director weighing up a company car, a car allowance or a personally owned vehicle should model each option against their own figures before committing, because the difference over a three-year lease can run into thousands of pounds.

Frequently Asked Questions

How is company car benefit in kind calculated?

Company car benefit in kind is calculated by multiplying the car's list price, including VAT, delivery and optional extras, by an appropriate percentage set by the car's CO2 emissions. The employee pays income tax on that figure at their marginal rate of 20%, 40% or 45%, and the employer pays Class 1A National Insurance at 15% on the same amount.

What is the electric car benefit in kind rate for 2026/27?

The electric car benefit in kind rate for the 2026/27 tax year is 4% of the car's list price. An electric car with a list price of £45,000 therefore produces a taxable benefit of £1,800, costing a higher-rate taxpayer £720 in income tax for the year. The rate rises to 5% in 2027/28.

When is the P11D deadline for company cars?

The P11D deadline is 6 July following the end of the tax year on 5 April. Employers must submit a P11D for each employee with a company car and a P11D(b) summarising Class 1A National Insurance. The Class 1A National Insurance must be paid by 22 July if paying electronically, or 19 July by post.

Do I still need a P11D if I payroll benefits?

If you payroll a company car, you report its taxable value through the payroll in real time and do not need to include that car on a P11D. You must still submit a P11D(b) to report and pay the Class 1A National Insurance due on payrolled benefits. Payrolling of benefits is becoming mandatory for most employers.

Is an electric company car worth it in 2026/27?

An electric company car is usually worth it in 2026/27 because the 4% benefit in kind rate produces a very low tax charge compared with a petrol or diesel car. A higher-rate taxpayer with a £45,000 electric car pays about £720 in tax for the year, often less than the tax on a cash car allowance of equivalent value.

How Blue Tick Can Help

Blue Tick Accountants advises limited company directors and employers on company car decisions, from calculating the exact benefit in kind to preparing and filing accurate P11D and P11D(b) returns. Blue Tick can model a company car against a car allowance or salary-sacrifice electric scheme using your real figures, so you choose the most tax-efficient option and stay compliant with HMRC. Head to our website and book a meeting now.

Conclusion

The tax cost of a company car turns almost entirely on its emissions: an electric car at 4% is a genuinely cheap benefit, while a high-emission petrol car can be an expensive one. Report the benefit correctly and on time through the P11D and P11D(b), pay the Class 1A National Insurance by the July deadline, and model a car allowance before you commit. The right structure can save thousands over a lease.

About the Author

This guide was written by Leon, founder of Blue Tick Accountants, a Guildford-based UK tax advisory and accountancy practice that helps limited company owners, landlords and the self-employed across the UK. Leon is a chartered tax adviser and accountant. This article was last reviewed for the 2026/27 tax year.

This article is intended for general informational purposes only and does not constitute tax, legal, or financial advice. Tax rules are subject to change and their application will depend on your individual circumstances. You should always seek advice from a qualified professional before taking action. Blue Tick Accountants accepts no liability for decisions made on the basis of this content.