Calculate the tax cost of UK benefits-in-kind: company car, medical insurance, gym membership and more.
List all your taxable benefits
Enter the cash-equivalent value for each benefit your employer provides — company car, medical insurance, gym, loan benefit, accommodation. Your P11D form (issued by 6 July) lists each figure.
Pick your marginal tax rate
Choose 20% basic, 40% higher, or 45% additional rate depending on where your total income falls. Scottish taxpayers can pick the matching Scottish band (21%/42%/45%/48%).
Review the income tax cost
The calculator multiplies total BIK by your marginal rate to show your personal tax bill. This appears as a tax-code restriction (lower code number) reducing your tax-free pay each month.
See the employer Class 1A NIC
Employer NI at 15% on the same total. Useful when negotiating — a £1,000 benefit costs the employer £1,150 plus your £400 income tax (higher rate).
Consider salary sacrifice alternatives
For pension, EVs, cycle-to-work and childcare, salary sacrifice can deliver the same benefit far cheaper than P11D-reported perks. Compare both routes before signing.
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Disclaimer: All results are estimates for guidance only and do not constitute financial, tax or legal advice. Always consult a qualified professional.