Salary sacrifice is the most effective tax planning available to an ordinary employee, and it requires no cleverness at all — you agree to a lower salary in exchange for a benefit your employer buys instead. Because the money never counts as pay, neither income tax nor National Insurance is charged on it, and your employer saves their National Insurance too.

It is also not free. There are real trade-offs, and one significant change already legislated for 2029.

How it works

You give up a contractual right to part of your cash pay, and your employer provides something of equivalent value instead. Your gross salary genuinely falls — this is a change to your employment contract, not a deduction from your payslip.

That distinction is the whole point. A deduction comes out of pay you have already been taxed on. A sacrifice reduces the pay that is taxed in the first place, so income tax, employee National Insurance, employer National Insurance and any student loan repayment are all worked out on the lower figure.

What it saves: two worked examples

A basic-rate taxpayer on £50,000 sacrificing 5% into a pension. £2,500 goes into the pension. Take-home falls from £39,519.60 to £37,719.60 — a drop of just £1,800. You have put £2,500 into your pension for £1,800 of spending money, because the £2,500 escaped 20% income tax and 8% National Insurance.

A higher-rate taxpayer on £60,000 sacrificing 10%. £6,000 into the pension, take-home down from £45,357.40 to £41,877.40 — a cost of £3,480 for £6,000 of pension. Above £50,270 the National Insurance rate is only 2%, but income tax is 40%, so the combined relief is 42%.

Your employer saves as well: 15% of whatever you sacrifice. On the £2,500 example that is £375 a year they no longer pay in secondary National Insurance. Many employers pass some or all of this into your pension too — always worth asking, because it costs them nothing.

The £100,000 case

Between £100,000 and £125,140 the personal allowance tapers away at £1 for every £2 earned, producing an effective marginal rate of 60% in England, Wales and Northern Ireland — around 67.5% in Scotland.

Sacrificing income in that band therefore attracts relief at that same effective rate. Someone on £110,000 who sacrifices £10,000 restores their full personal allowance and gets roughly 60% relief plus 2% National Insurance. It is the highest-value pension contribution available anywhere in the UK system.

Salary sacrifice versus relief at source

Not every workplace pension is salary sacrifice. Under relief at source, contributions come out of your net pay and the provider reclaims basic-rate relief; higher-rate taxpayers claim the rest through Self Assessment.

The difference is National Insurance. Relief at source gives income tax relief only, so a basic-rate taxpayer gets 20% rather than 28%. It also does not reduce student loan repayments, because gross pay is unchanged. If your employer offers both, sacrifice is almost always better — and if they only offer relief at source, it is worth asking why.

Electric cars

EV salary sacrifice has become the most popular non-pension scheme, because company car tax on electric vehicles is still very low. The benefit-in-kind rate for a zero-emission car is 4% in 2026/27, rising by one point in 2027/28 and then by two points a year to a cap of 9% in 2029/30.

You sacrifice the lease cost from gross pay and pay benefit-in-kind tax on 4% of the car's list price. For a £40,000 car that is £1,600 of taxable benefit — £320 a year for a basic-rate taxpayer. Against a personally financed lease paid from taxed income, the saving is usually substantial.

The catch is commitment. These are typically three or four year agreements, and leaving your job usually means an early termination charge. The rising benefit-in-kind rates also mean the deal gets slightly worse each year of the term.

Cycle to work

The smallest and simplest scheme. Your employer buys the bike, you sacrifice the cost over twelve or eighteen months, and there is no benefit-in-kind charge if the bike is mainly used for commuting. A basic-rate taxpayer saves around 28% and a higher-rate taxpayer around 42%.

Employers often cap schemes at £1,000, though there is no statutory limit for employers with the right consumer credit permissions. At the end of the hire period you normally pay a small market-value fee to own the bike outright.

The real downsides

Your gross salary is genuinely lower. Mortgage lenders assess affordability on gross pay, and a large sacrifice can reduce how much you can borrow. Some lenders add it back; many do not. If you are buying a house in the next year, this alone may be reason to pause.
Statutory pay can fall. Statutory maternity, paternity and sick pay are based on average earnings after sacrifice. Anyone planning to take parental leave should consider suspending it beforehand.
Death-in-service cover is often a multiple of salary, and some schemes use the reduced figure.
You cannot go below the National Minimum Wage. This is a hard legal floor and it constrains lower-paid employees most.
The money is locked up. Pension contributions are inaccessible until age 55, rising to 57 in 2028.
Contributory benefits depend on your National Insurance record, though earnings above the lower earnings limit still preserve a qualifying year.

What changes in April 2029

At the 2025 Budget the government announced a cap on the National Insurance advantage of pension salary sacrifice, taking effect from April 2029. From then, only the first £2,000 sacrificed into a pension each year will be free of Class 1 National Insurance. Anything above that will be treated as earnings for National Insurance, for both employee and employer.

The maximum National Insurance saving will therefore become about £160 a year for a basic-rate employee and £300 for the employer. Income tax relief is not affected — pension contributions remain fully relievable against income tax, and the change does not touch EV or cycle-to-work schemes.

Until April 2029 the current rules apply in full, so the examples above hold for 2026/27, 2027/28 and 2028/29.

See it on your own salary

Our salary sacrifice calculator compares take-home pay with and without a sacrifice and shows the income tax, employee National Insurance and employer National Insurance saved. The pension calculator shows what a contribution really costs you after relief.

For the underlying rates, see National Insurance Explained and UK Tax Bands 2026/27 Explained.