Salary sacrifice is one of the most tax-efficient arrangements available to UK employees — yet many workers either don't use it or don't fully understand how much it's saving them. This guide uses real 2026/27 numbers.
What is salary sacrifice?
Salary sacrifice (sometimes called "salary exchange") is a formal agreement between you and your employer. You agree to reduce your contractual gross salary by a set amount, and your employer pays that amount directly into your chosen scheme — most commonly your workplace pension.
Your official gross pay is reduced before tax and National Insurance are calculated. This means you save both income tax and employee NI on the sacrificed amount — not just income tax.
How does salary sacrifice save tax and NI?
Here's a concrete 2026/27 example. You earn £40,000 and contribute £200/month to your pension:
| Scenario | Monthly gross | Monthly tax | Monthly NI | Real cost |
|---|---|---|---|---|
| No pension | £3,333 | £373 | £175 | £200 |
| Relief at Source | £3,333 | £333 | £175 | £160 |
| Salary Sacrifice ✓ | £3,133 | £333 | £159 | £144 |
Who benefits most from salary sacrifice?
Higher rate taxpayers (income above £50,270) save 42p per £1 sacrificed. Basic rate taxpayers save 28p per £1. If you're close to the £100,000 threshold where the personal allowance begins tapering, salary sacrifice can be extraordinarily powerful — reducing your adjusted net income below £100k restores your full personal allowance.
What can I sacrifice salary into?
- Pension contributions — the most widely available and most tax-efficient.
- Cycle to Work — buy a bike and safety equipment tax-free, typically up to £3,000.
- Electric Vehicle leasing (ULEV) — the BiK rate for fully electric vehicles is just 2% for 2026/27, making this exceptionally efficient for higher earners.
- Childcare vouchers — legacy scheme (closed to new entrants, replaced by Tax-Free Childcare), but existing members can continue.
Does salary sacrifice affect my state pension?
It can reduce your NI-able earnings slightly. Your state pension entitlement depends on 35 qualifying years of NI contributions. For most full-time workers, even with significant sacrifice, earnings stay well above the Lower Earnings Limit (£6,396 in 2026/27). The immediate tax saving almost always outweighs the marginal state pension impact.
Does salary sacrifice affect my mortgage?
Potentially yes. Your official gross salary will be lower than your pre-sacrifice salary, and most lenders use gross income to determine maximum lending. Some lenders will "add back" the sacrificed amount when assessing affordability — ask your mortgage broker specifically about this before increasing your sacrifice amount significantly.
Can my employer refuse salary sacrifice?
Yes. It requires a contract amendment, so employer agreement is needed. However, it's in your employer's interest too — they save 13.8% employer NI on the sacrificed amount. A £200/month sacrifice saves your employer £27.60/month per employee. Many forward-thinking employers pass some or all of this saving back as extra pension contributions.
How to set up salary sacrifice
- Contact your HR or payroll team and request to opt in.
- They will issue a salary sacrifice agreement — a document showing the new lower gross salary.
- Your next payslip will show the lower gross, with pension contributions appearing separately.
- Your tax code doesn't change — but your taxable gross will be lower.
For official HMRC guidance, see GOV.UK salary sacrifice guidance. To understand how your pension deductions appear on your payslip, read our pension deduction explainer.