The core formula
A company car’s taxable benefit is usually list price × appropriate percentage, adjusted for some contributions and part-year availability. Your own income-tax rate is then applied to that benefit to work out the employee tax cost.
What changes the number fastest
- The BIK percentage, which depends mainly on CO2 and sometimes electric range.
- The list price, because a low percentage on a high-priced car can still create a meaningful bill.
- The separate fuel benefit if private fuel is provided and not fully reimbursed.
Best next page
Use Company Car and EV BIK Calculator for the actual 2026/27 estimate.
Official source: GOV.UK calculate tax on company cars.