Most employers know the basic idea of salary sacrifice. The employee gives up some salary and gets a benefit instead – everyone saves on tax and National Insurance.
Unfortunately, like many things in payroll, salary sacrifice isn’t as simplistic as it first appears.
The number of salary sacrifice arrangements running quietly in businesses across the UK, with documentation that would not survive an HMRC challenge, NMW calculations that have not been touched since the scheme launched, and employees who have no idea their maternity pay has just taken a significant hit, is genuinely alarming.
What is salary sacrifice?
Salary sacrifice is a contractual arrangement whereby an employee agrees to reduce their gross salary in exchange for a non-cash benefit provided by the employer. That reduction means they pay income tax and National Insurance on a lower salary, and the employer pays less employer’s NIC too.
That last point matters particularly right now. Since the increase in employer NIC to 15% in April 2025, and the secondary threshold has dropped from £9,100 to £5,000. For a business with ten employees earning £30,000 each, that is roughly £6,150 extra per year in ER’s NIC. Salary sacrifice is one of the most effective ways to claw some of that back.
But the arrangement has to be set up correctly. That means a proper written agreement, either a new contract of employment or a signed amendment to the existing one, that specifies the original salary, the reduced salary, the exact benefit being provided, the duration, and what happens if circumstances change.
Without that documentation, HMRC can argue the arrangement is not valid, and back-dated tax and NIC charges will be applied for the employer and employee.
The three benefits still worth doing
Also, since April 2017, Optional Remuneration Arrangement (OpRA) rules have changed the picture significantly. Under OpRA, most sacrificed benefits are taxed on the higher of the amount sacrificed or the normal benefit-in-kind value. That largely removes the tax advantage for things like private medical insurance, gym memberships, and non-electric company cars.
Three categories remain genuinely tax-efficient:
Pension contributions
Pension contributions are still the most popular and effective option. The employee gets income tax relief at their marginal rate, plus full NIC relief for both parties – at least until April 2029, when an annual £2,000 cap on pension NIC relief comes in. More on that in a moment.
Electric Vehicles
Electric vehicles are fully protected from OpRA rules and offer exceptional value. The benefit-in-kind rate for EVs is currently 4% for 2026-27, rising gradually to 9% by 2030-31. A £40,000 EV on salary sacrifice could save an employee £12,000 to £20,000 over three years compared to buying personally, depending on their tax bracket.
Cycle to Work
Cycle to work schemes also remain OpRA-exempt. A higher-rate taxpayer buying a £1,500 bike through sacrifice pays an effective cost of around £870 after tax and NIC relief – a saving of £857.
If you are running salary sacrifice for anything outside these three categories, you need to check carefully whether you are actually delivering the benefit you think you are.
The change you need to plan for now
From 6 April 2029, NIC relief on pension salary sacrifice will be capped at £2,000 per year. Salary sacrificed above that will attract employee NIC at the normal rate – 8% up to the upper earnings limit, 2% above.
Income tax relief is unaffected. Employer contributions made outside of sacrifice are unaffected. Electric vehicles and cycles to work schemes are unaffected.
For most employees contributing modest amounts, the impact will be limited. For higher earners using sacrifice to contribute £10,000 or more annually, it is worth reviewing the strategy now rather than in 2029. Combining capped pension sacrifice with an EV scheme, for example, gives access to two of the most tax-efficient options available simultaneously.
Where things go wrong
National Minimum Wage violations
The most common and most serious compliance failure is the National Minimum Wage (NMW). Salary sacrifice cannot reduce an employee’s pay below the NMW for their age bracket. Not even by a penny. Paying below NMW is a criminal offence, even if the employee agreed to the arrangement. HMRC can impose penalties of up to 200% of the underpayment and will publicly name the business.
The problem is not usually that employers set out to breach NMW. It is that they set up the scheme, do not build in an annual review, and then April comes around with new increased NMW rates. An employee who was safely above the threshold in March may not be in April. If the salary sacrifice arrangement is not suspended immediately, you are in breach.
Impact on Statutory Payments
The other issue that catches people out consistently is statutory payments. Salary sacrifice reduces gross pay. Statutory Maternity Pay, Statutory Sick Pay, and Statutory Paternity Pay are all calculated on gross pay. So, an employee who has been sacrificing £5,000 annually for pension contributions may find their
SMP is meaningfully lower than they expected. If no one told them that before they signed the agreement, you have a problem.
Getting it right
Salary sacrifice done well is genuinely one of the most effective tools available for structuring employee remuneration. It saves money for employers and employees alike, supports recruitment and retention, and, in the case of EVs and cycle to work, aligns with sustainability objectives too.
But it requires proper setup, watertight documentation, annual compliance reviews, and clear communication with employees from the start.
If you are setting up salary sacrifice for the first time, or you have an existing scheme you have not reviewed recently, talk to us. We can help you make sure it is doing what you think it is, and that it will still be compliant when April comes around.
