Pension Salary Sacrifice vs Relief at Source

These are 2026/27 annual examples for England, Wales or Northern Ireland, with the standard Personal Allowance, employee NI category A, and no student loans, other income or other pension contributions. The £2,400 is the gross amount reaching the pension, not the amount deducted from your bank balance. Ordinary employer contributions are excluded and no employer NI saving is added to the pot.

At £30,000, sacrificing £2,400 saves £480 Income Tax and £192 employee NI: £2,400 − £480 − £192 = £1,728 less cash pay. At £60,000, that contribution falls entirely within the 40% tax and 2% NI bands, so the cash reduction is £1,392.

Under relief at source, you pay £1,920 and the provider adds £480. In the £60,000 example, a further £480 of higher-rate relief brings the eventual cost to £1,440. That extra relief may need to be claimed from HMRC; it is not another provider top-up and is not necessarily reflected in the same month’s payslip. Without it, the initial cash cost remains £1,920.

A net pay arrangement deducts the £2,400 before Income Tax but does not reduce NI earnings. It therefore has the same final cash cost as fully claimed relief at source in these examples, with different timing. Monthly figures above are annual amounts divided by 12, not exact payroll deductions.

Open the £30,000 examples: £200/month pension salary sacrifice, £160/month relief at source plus the provider top-up, or £200/month net pay contribution.

Scottish rates, low earnings, contributions crossing a tax band, the allowance taper and student loans can change this comparison. Do not apply these percentages to your whole salary. Check your scheme’s contribution basis, National Minimum Wage limit and any effect on statutory pay or salary-linked benefits before changing an arrangement.

HMRC says relief at source means the member pays a net contribution and the pension scheme administrator reclaims the basic-rate tax relief from HMRC. So if £100 is meant to go into the pension, the member normally pays £80 and the scheme claims the other £20.

If you pay higher-rate tax, HMRC says you may need to claim the extra relief separately through Self Assessment or your tax office.

Under pension salary sacrifice, you give up part of your salary and the employer pays that amount into the pension instead. GOV.UK says this can mean both you and your employer pay less tax and National Insurance in some cases.

The money goes in as an employer contribution, so you do not wait for the scheme to add basic-rate relief in the same way.

The main reason is National Insurance. Relief at source helps on income tax, but it does not usually create the same employee-NI saving as salary sacrifice.

That means two pension routes can produce the same gross pension contribution while reducing take-home pay by different amounts.

Salary sacrifice changes contractual cash pay, so it can affect statutory-pay calculations and some borrowing or affordability checks. GOV.UK also says employers must not let sacrifice reduce cash earnings below the National Minimum Wage.

Relief at source usually does not create those same contract-level issues, because the cash salary is not being rewritten.

The examples isolate the tax and NI effect; they do not establish which arrangement suits everyone. Ask payroll whether contributions use the whole salary or qualifying earnings, whether employer NI savings are shared, and which salary is used for benefits or borrowing references. The workplace-pension guide explains which monthly amount to enter in the calculator.

If you earn below the Income Tax threshold, use the specific low-earner pension-relief rules rather than the basic-rate example above. Scottish tax relief and contributions crossing thresholds also need their own calculation. See how relief at source and extra tax-relief claims work.

Future change, not the 2026/27 calculation: the published reform is due from 6 April 2029. Pension contributions funded by salary sacrifice above an annual £2,000 limit are due to attract employee and employer NI. Income Tax relief is retained, and ordinary employer pension contributions are treated separately.

See the official reform note for scope and implementation updates. Do not project the current NI saving unchanged beyond its applicable tax year.