Salary Sacrifice Explained: How It Works and How Much It Saves
Salary sacrifice is one of the most effective and least understood ways to improve your finances as an employee. The idea is simple: you agree with your employer to reduce your contractual salary, and they pay the difference straight into your pension instead.
Why it beats an ordinary pension contribution
A normal pension contribution saves you Income Tax but you still pay National Insurance on the money first. With salary sacrifice the pay never reaches you, so it escapes both Income Tax and National Insurance. Many employers also pass on some or all of the employer National Insurance they save (15%) by adding it to your pot, making it better still.
How much it actually saves
Because you avoid tax and employee National Insurance, the real cost of each pound you sacrifice depends on your tax band:
| Your tax band | You save | £1 in pension costs you |
|---|---|---|
| Basic rate | 28% | 72p |
| Higher rate | 42% | 58p |
| £100k–£125,140 trap | 62% | 38p |
| Additional rate | 47% | 53p |
What £1 in your pension really costs in take-home pay, by tax band. The higher your marginal rate, the more the taxman effectively chips in — and the cheaper each pound becomes.
So a higher-rate taxpayer who sacrifices £200 a month puts £2,400 a year into their pension at a cost of about £1,392 in take-home pay — before any employer top-up.
The gain is biggest exactly where tax bites hardest: in the £100k band, a pound in your pension costs just 38p of take-home.
What you can sacrifice
Pension is the big one, but the same mechanism is used for cycle-to-work schemes, electric-car leasing, and sometimes additional holiday or workplace nurseries. The tax treatment varies by scheme, but the principle — paying from pre-tax salary — is the same.
The watch-outs
- Mortgage affordability. Sacrifice reduces your gross salary, and some lenders lend against that lower figure.
- Salary-linked benefits. Life cover, sick pay and other perks set as a multiple of salary may be based on the reduced figure unless your employer uses a "reference salary".
- Statutory pay. Maternity and similar statutory payments are based on earnings, so heavy sacrifice in the qualifying period can reduce them.
- The minimum wage floor. You cannot sacrifice below the National Minimum Wage.
The bottom line
For most employees with access to it, salary sacrifice into a pension is among the best-value things you can do with your money — and the gain is largest exactly where tax bites hardest, in the £100k band and at higher rate. Work out your own figure before you set the amount.
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Common questions
Sources
GOV.UK — Salary sacrifice and PAYE and GOV.UK — pension tax relief. See our full methodology and rates.
This article is general information for the 2026/27 tax year and not personalised financial advice. Check your own loan details in your student loan account and verify figures against GOV.UK before making decisions.