Salary Sacrifice for Cars

This blog pulls together the practical UK tax and payroll rules you’ll need if you’re thinking about salary sacrifice for cars, especially electric ones — including how HMRC treats the arrangement, the valuation traps you must watch, and where the biggest savings (or risks) lie.

In the UK a salary sacrifice isn’t just a deduction, it’s a contractual variation where an employee gives up cash pay in exchange for a benefit — and HMRC only accepts it if the variation to pay terms is genuine and documented. The detailed HMRC guidance on this is in the optional remuneration arrangements (OpRA) section of the Employment Income Manual.

Under OpRA, benefits (like a company car via salary sacrifice) are generally valued for tax/NICs as the higher of the cash foregone or the normal cash-equivalent benefit value — that’s the core trap many miss.

There’s a useful exception for low‑emission vehicles: cars with CO₂ emissions of 75g/km or less (including many EVs) are excluded from the OpRA revaluation rule and are taxed under the ordinary benefit‑in‑kind rules instead. This makes electric and very low‑emission cars especially favourable in a salary sacrifice context.

For electric cars, the benefit‑in‑kind (BiK) rates are very low compared with petrol/diesel models — around 3% for tax year 2025/26, rising to about 4% in 2026/27. That’s much lower than the percentages charged on higher‑emission cars and a big part of why EV salary sacrifice schemes are so tax‑efficient right now.

If you payroll car benefits (the BiK) instead of reporting them on P11D, you need to register the benefit with HMRC before the tax year starts and then operate payrolling through your payroll software — otherwise you default back to P11D reporting and Class 1A NICs.

One often‑overlooked legal risk is National Minimum Wage (NMW): salary sacrifice reduces gross pay, so if a director (or any worker) has an employment contract — not just a statutory office‑holder role — reducing pay below NMW for the contracted work could create exposure under NMW rules. HMRC’s NMW manual discusses how directors are treated.

In practice, the biggest pitfalls people run into are:

• Arrangements that are not genuinely documented as a variation to pay terms — HMRC can challenge these under OpRA.

• Cutting salary below NMW where contracts trigger worker protections.

• Not registering benefits to be payrolled — leading to unexpected P11D reporting and employer NIC timing issues.

This is why advisers often recommend: confirm whether the director’s role is contract plus office‑holder before proceeding, and if you do go ahead, produce a clear contract variation letter spelling out the sacrifice and benefit terms and register the benefit for payrolling early.