UK guide

Salary Sacrifice Explained: How It Saves You Tax

Salary sacrifice lets you give up part of your gross pay in exchange for a pension contribution. Because the money never hits your payslip as salary, you pay no income tax and no National Insurance on it. This guide walks through how the mechanic works, who qualifies, and what the numbers look like at typical UK incomes for the 2026 to 2027 tax year.

What salary sacrifice actually is

A salary sacrifice arrangement is a formal change to your employment contract. You agree with your employer that your gross salary will be reduced by a fixed amount or percentage, and that the employer will pay an equivalent contribution into your workplace pension instead. HMRC treats the sacrificed amount as employer pension contribution, not as your earnings.

The reduction in gross pay is what creates the tax saving. Income tax bands, National Insurance, student loan repayments, and the High Income Child Benefit Charge are all calculated on your post-sacrifice salary.

Pre-tax vs post-tax contributions

A standard relief-at-source pension contribution comes out of your net pay. HMRC then tops it up with basic-rate relief (currently 20%), and higher or additional-rate payers have to claim the extra relief through Self Assessment. You still pay National Insurance on the gross income before contributing.

Salary sacrifice short-circuits all of that. The pension contribution is taken from gross pay before any tax is calculated, so the full relief is automatic and you also avoid the employee National Insurance charge. That NI saving is the part many people miss.

Who qualifies

Salary sacrifice has to be offered by your employer; you cannot set it up unilaterally. The arrangement must be in place before the pay is earned, and your post-sacrifice gross salary cannot drop below the National Minimum Wage. HMRC also requires that the contract change is documented in writing.

Most large UK employers run salary sacrifice for pensions, cycle-to-work, electric vehicles, and additional annual leave. Smaller employers often do not, because the payroll setup carries some admin overhead. If your employer does not offer it, a normal relief-at-source contribution still gives you income tax relief but no NI saving.

Worked example at £50,000

Assume a basic-rate taxpayer on a £50,000 salary in England, Wales, or Northern Ireland, sacrificing £5,000 into the workplace pension. The personal allowance is £12,570 and the basic rate is 20% up to £50,270. Employee NI is 8% between the primary threshold and the upper earnings limit for 2026 to 2027.

Take-home falls by £3,600 but a £5,000 contribution lands in the pension. The £1,400 difference is £1,000 of income tax relief plus £400 of employee NI you no longer pay. Some employers also pass back the 13.8% employer NI saving, which would add another £690.

Worked example at £80,000

At £80,000 you are a higher-rate taxpayer. The 40% band runs from £50,270 to £125,140. Employee NI drops to 2% above the upper earnings limit. Sacrificing £10,000 takes the gross salary to £70,000.

Net pay drops by £5,800 to fund a £10,000 contribution. That is £4,000 of income tax relief and £200 of employee NI saved at the 2% marginal rate. The higher your marginal rate, the larger the income tax slice of the saving.

The National Insurance bonus

Relief at source returns the income tax but not the NI. Salary sacrifice removes both. limit and 2 above it, on top of the marginal income tax rate.

Employers also save 13.8% employer NI on the sacrificed amount. A growing number of UK employers pass that saving back into the pension as well; HMRC permits this as long as the contract is clear.

The £60,000 annual allowance

For the 2026 to 2027 tax year HMRC sets the pension annual allowance at £60,000. This is the total of employee, salary sacrifice, and employer contributions you can receive in a tax year without an annual allowance charge. The figure is gross of any tax relief.

Two things can shrink the allowance. The tapered annual allowance reduces it by £1 for every £2 of adjusted income above £260,000, down to a floor of £10,000. The Money Purchase Annual Allowance drops it to £10,000 if you have already flexibly accessed a defined contribution pension. You can also carry forward unused allowance from the previous three tax years if you were a pension scheme member in those years.

Risks and trade-offs to weigh

Reducing your gross salary affects anything that is calculated on it. Mortgage affordability is the most common one. Lenders look at gross pay; some will accept the pre-sacrifice figure if you can prove the arrangement, others will not. Statutory maternity pay, redundancy pay, and life cover that is a multiple of salary can all be based on the lower figure too.

The pension money is locked until age 55, rising to 57 from April 2028. You also need to keep enough cash flow at the lower take-home figure. None of these rule salary sacrifice out, but they should be checked before you fix a contribution rate.