Company car tax on a BMW X5 runs from roughly £1,600 a year on the xDrive50e plug-in hybrid to over £10,000 a year on the petrol or diesel variants. The gap is that wide because HMRC taxes each model on its CO2 emissions and list price, and the X5 range covers everything from a long-range plug-in hybrid to high-emission petrol and diesel engines. Picking the right powertrain is the single biggest lever, and missing the fuel benefit charge can push the real cost well past what most drivers expect.
How the Tax Is Calculated
When your employer lets you use an X5 privately, HMRC treats that private use as a benefit in kind. The tax is worked out in three steps: take the car’s P11D value (list price including VAT, options, and delivery), apply a BIK percentage set by the car’s CO2 emissions, then multiply by your income tax rate.1GOV.UK. Calculate Tax on Employees’ Company Cars
The BIK percentage does most of the damage. For 2026/27 the scale starts at 4% for zero-emission and long-range plug-in hybrid vehicles and climbs to a ceiling of 37% for cars emitting 155 g/km or more.2GOV.UK. Work Out the Appropriate Percentage for Company Car Benefits (480: Appendix 2) Two X5s parked side by side can therefore produce very different tax bills.
Rates for Each X5 Variant
Petrol and Diesel: xDrive40i and xDrive40d
Both the xDrive40i petrol and xDrive40d diesel produce well over 170 g/km of CO2 under WLTP testing, which puts them at the 37% maximum BIK rate for 2026/27.2GOV.UK. Work Out the Appropriate Percentage for Company Car Benefits (480: Appendix 2) Non-RDE2 diesels normally attract a 4% surcharge, but the combined rate cannot exceed 37%, so the diesel X5 is already at the cap.
On a petrol xDrive40i with a P11D value of around £68,000, the 37% rate creates a taxable benefit of roughly £25,000. A higher-rate taxpayer at 40% owes about £10,000 a year; a basic-rate taxpayer at 20% owes about £5,000.3GOV.UK. Income Tax Rates and Personal Allowances
xDrive50e Plug-In Hybrid
The xDrive50e emits between 1 and 50 g/km and has an electric-only range in the 40-to-69-mile band under WLTP, which puts it in the 10% BIK band for 2026/27.2GOV.UK. Work Out the Appropriate Percentage for Company Car Benefits (480: Appendix 2) Applied to a P11D value of about £82,090:
- Taxable benefit: £82,090 × 10% = £8,209
- Tax at 20% (basic rate): £1,642 a year
- Tax at 40% (higher rate): £3,284 a year
- Tax at 45% (additional rate): £3,694 a year
Even though the xDrive50e has a higher list price than the petrol or diesel X5, the 10% rate means a higher-rate taxpayer pays roughly a third of what they would on the xDrive40i. That is why the plug-in hybrid dominates X5 company car orders.
One warning on the range figure. If the certified electric range falls below 40 miles, the BIK rate jumps to 14%; below 30 miles it moves to 16%, and so on.2GOV.UK. Work Out the Appropriate Percentage for Company Car Benefits (480: Appendix 2) On an £82,000 car, the difference between 39 and 40 certified miles is about £3,280 in annual taxable benefit. Check the WLTP figure on the V5C for your specific model year, not the marketing headline.
The Fuel Benefit Charge
If your employer pays for fuel you use privately, a second charge lands on top of the car benefit. It is calculated from a flat multiplier of £29,200 for 2026/27, regardless of how much fuel you actually burn.4legislation.gov.uk. Income Tax (Earnings and Pensions) Act 2003 – Section 149 Multiply £29,200 by the BIK percentage, then by your tax rate.
For a higher-rate taxpayer, that means an extra £1,168 a year on the xDrive50e (£29,200 × 10% × 40%), or £4,322 a year on the petrol xDrive40i at 37%. You can avoid the charge entirely by reimbursing your employer for every penny of private fuel by 6 July after the end of the tax year. Partial reimbursement does nothing: it is all or nothing.5GOV.UK. Taxable Fuel Provided for Company Cars and Vans (480: Chapter 13) For most drivers doing modest private mileage, reimbursing is cheaper than absorbing the flat charge.
What Sits Inside the P11D Value
The P11D value is the car’s published list price on the day before it was first registered, including VAT, any applicable duties, and delivery charges. It excludes the vehicle registration fee.6GOV.UK. How to Work Out the Benefit of a Company Car (480: Chapter 12)
Every factory-fitted option adds to it. On an X5, M Sport packages, technology upgrades, and premium paint can add several thousand pounds, and each addition raises your taxable benefit for the life of the car. Accessories fitted later count too if they cost £100 or more and were available at time of order. Fleet discounts and negotiated prices do not reduce the P11D value: it is always the published list price, not what your employer actually paid.
What Your Employer Pays
The employer owes Class 1A National Insurance on the full BIK value at 15%.7GOV.UK. National Insurance Rates and Categories: Contribution Rates For the xDrive50e that is roughly £1,231 a year; for a petrol xDrive40i at 37% BIK on £68,000, roughly £3,774. If the employer also provides private fuel, Class 1A applies to the fuel benefit as well. These figures often shape which X5 variants a fleet policy will actually offer, and it is another reason the xDrive50e tends to be the preferred choice.
How the Tax Reaches Your Payslip
For 2026/27, most employers still report the car benefit on a P11D form submitted to HMRC by 6 July after the tax year ends.8GOV.UK. Expenses and Benefits for Employers: Deadlines HMRC then adjusts your tax code so the extra tax comes out through PAYE across the year rather than as a lump sum.9GOV.UK. Expenses and Benefits for Employers: Reporting and Paying You will get a P2 Coding Notice explaining how the benefit has been built into your code.10HM Revenue and Customs. PAYE Manual – Coding: Codes: How They Are Used and Calculated: P2 Notice of Coding Check it against the P11D value and CO2 rating before deductions start.
Mandatory payrolling of benefits in kind was originally due in April 2026 but has been pushed back to April 2027.11GOV.UK. Technical Note: Mandating the Reporting of Benefits in Kind and Expenses Through Payroll Software: An Update From then, company car tax will be deducted in real time through payroll software instead of reconciled after the year end. Some employers already payroll benefits voluntarily. The total tax owed across the year is the same either way.
Salary Sacrifice
p>If you take the X5 through salary sacrifice, the Optional Remuneration rules apply. HMRC taxes you on whichever is higher: the normal BIK value, or the salary you gave up.12GOV.UK. Expenses and Benefits: Company Cars and Fuel: What’s Exempt On the xDrive50e, the 10% BIK often produces a taxable value below the salary sacrificed, so the arrangement can still work well. On the petrol or diesel X5 at 37%, the BIK figure is usually already higher than the salary given up, so salary sacrifice offers little tax advantage. Compare the two figures against the specific lease quote before signing.
Cutting the Bill
The most effective step by far is choosing the xDrive50e. No amount of tweaking on the petrol or diesel variants closes the gap that the BIK rate creates.
- Reimburse private fuel in full. The flat fuel benefit charge almost always costs more than the actual fuel, especially on the plug-in hybrid where many short trips use none.
- Be careful with the options list. Every factory option feeds directly into the P11D value, and the extra tax runs for the life of the car.
- Confirm the certified WLTP electric range on the xDrive50e for your model year. The 40-mile boundary is the difference between the 10% and 14% BIK bands.
- Check your P2 Coding Notice when it arrives. Errors compound over the year, and underpayments come back later with interest.
Handled with a bit of attention, X5 company car tax is manageable. The xDrive50e in particular keeps annual tax below what many drivers pay on cars costing half as much, because a 10% BIK rate on an £82,000 list price is still a far smaller number than 37% on £68,000.