Pillar guide · Salary sacrifice

Salary sacrifice for pensions — the UK guide.

How the tax and NI saving works, how the £100k personal allowance taper and child benefit charge interact with pension contributions, and the trade-offs to check before changing pay.

By Pension Bible editorial team·Last reviewed 12 May 2026·15 min read

What salary sacrifice actually is

Salary sacrifice is one of those phrases that sounds more complicated than it is. The mechanic is simple: you agree, in writing, to reduce your contractual gross salary by some amount each month, and your employer agrees to pay that same amount directly into your workplace pension as an employer contribution.

Because the sacrificed amount is paid as an employer pension contribution rather than cash salary, it is normally outside employee income tax and employee National Insurance. The employer also normally avoids employer National Insurance on the sacrificed amount. Whether any employer NI saving is added to the pension depends on the employer's scheme rules.

Compare that to the default way most personal pensions work, called relief at source. Under relief at source, you contribute out of post-tax salary and HMRC adds basic-rate tax relief to your pension. On a £1,000 gross contribution, a basic-rate taxpayer pays £800 and HMRC adds £200. The same £1,000 routed through salary sacrifice can reduce income tax by £200 and employee NI by £80 for a category A employee in the main NI band. If the employer passes on its own 15% NI saving, the pension contribution can be higher again.

You can run the exact numbers for your own salary using our salary sacrifice calculator or the pension tax relief calculator, which lets you flip between relief-at-source and salary sacrifice for the same inputs.

Why salary sacrifice can beat relief at source

The short answer is National Insurance. Relief at source recovers income tax but does not recover employee NI. Salary sacrifice normally means the sacrificed amount is not treated as cash salary, so employee NI is not due on it.

For a basic-rate taxpayer earning between £12,570 and £50,270, the employee NI difference is 8%. Every £1,000 sacrificed can reduce income tax by £200 and employee NI by £80, compared with £200 income-tax relief on the same gross contribution through relief at source.

For a higher-rate taxpayer earning above £50,270, the income tax saving is 40% and the employee NI saving is normally 2%. Sacrificing £1,000 at the higher rate can therefore reduce personal tax and NI by about £420, before any employer NI pass-through. Relief-at-source contributions may still require higher-rate taxpayers to claim extra relief from HMRC.

For a worker earning £50,000, the difference between the two routes is not trivial — we break it down on the pension on £50k salary page. And for round-number intermediate cases like £30k, £40k and £70k, the same calculation framework applies with slightly different NI thresholds baked in.

The employer NI angle

When you salary-sacrifice, your employer normally stops paying 15% employer National Insurance on the sacrificed portion.

What happens to that saving is entirely up to the employer. Broadly, there are three models you'll find in the wild:

1. The employer keeps it. The business keeps the payroll cost reduction. You still benefit from your own tax and NI saving, but the 15% employer NI saving is not added to your pension.

2. The employer passes it on in full. The 15% saving is added to the pension contribution. If you sacrifice £1,000, your employer pays £1,150 into your pension.

3. Split or net-of-tax pass-through. Some schemes pass on part of the NI saving. Others calculate a net amount. The policy document or payroll team should explain the exact treatment.

The distinction matters because it changes the pension contribution for the same reduction in take-home pay. Ask HR or payroll whether employer NI is passed on before relying on a calculator result.

The £100k personal allowance taper

If adjusted net income sits between £100,000 and £125,140, pension contributions can have an additional effect because they may restore some personal allowance.

UK income tax has a quirk that doesn't get taught alongside the headline 20/40/45 rates: the personal allowance of £12,570 starts to be withdrawn once your adjusted net income crosses £100,000. You lose £1 of personal allowance for every £2 of income above £100k. The personal allowance is fully withdrawn by the time your adjusted net income hits £125,140.

In the £100,000 to £125,140 band, you are paying 40% income tax on each additional pound and losing 50p of personal allowance on each pound, which itself triggers another 20p of tax. That's a 60% effective marginal rate on every pound earned in that band. Add the 2% employee NI and the true take-home rate on a marginal pound is roughly 38p in every £1.

Salary sacrifice reduces adjusted net income. For every pound sacrificed in the £100k to £125,140 band, the income-tax effect can include 40p of higher-rate tax, restored personal allowance and 2p of employee NI. A simplified £10,000 sacrifice in this band can reduce take-home pay by about £3,800 while adding £10,000 to the pension before any employer NI pass-through. The exact result depends on the full income picture.

This is why the £100k to £125,140 band is one of the most sensitive salary-sacrifice ranges. It is also an area where bonuses, benefits in kind, Gift Aid, existing pension contributions and annual allowance limits can change the result.

For workers in this band, we have pre-filled context-specific versions of the calculator at £100,000 and £125,000. The maths changes quite sharply across that £25k window and the pre-filled pages make the "what if I sacrifice back below £100k" scenario visible in pounds rather than percentages.

The child benefit angle (HICBC)

If you have kids and your household finances depend on child benefit, there's another marginal-rate story running in parallel at a lower income band. From 2024, the High Income Child Benefit Charge (HICBC) applies between £60,000 and £80,000 of the higher-earning parent's adjusted net income. Between those thresholds, child benefit is clawed back at 1% for every £200 of income — meaning it's fully withdrawn at £80,000.

The clawback can be substantial. A family with two children receiving child benefit gets around £2,337 a year in 2026/27. Across the £20,000 clawback band that's an effective extra tax of around 11.7% on each pound earned. Stack it on top of the 40% higher-rate income tax and 2% NI and the marginal rate can sit in the low-to-mid 50s.

Salary sacrifice reduces adjusted net income. Bringing the figure back under £60,000 can remove the charge; a partial reduction towards £60,000 can reduce it. For households where one parent sits in the £60k-£80k band, pension contributions can therefore affect both pension saving and the child benefit charge.

It's worth noting that you can keep the Child Benefit claim even if you opt out of receiving payments. This matters because the claim can protect the claiming parent's National Insurance credits for state pension purposes, so families should generally stay registered even where HICBC makes receiving the cash unattractive.

The trade-offs — what can go wrong

None of the above means salary sacrifice is a free lunch. The quiet cost is that, from the moment you sign the contractual variation, your "salary" as recorded by payroll is the lower figure. That has knock-on effects outside the pension world that you need to know about.

Mortgage applications. Mortgage lenders assess affordability against your post-sacrifice gross salary, because that's what appears on your payslip and P60. A worker on £55,000 sacrificing 10% into pension shows up as earning £49,500. With most lenders working on income multiples of 4.5x, that single change reduces theoretical maximum borrowing by around £24,750. Some lenders will add sacrificed amounts back on with documentation; many won't. If you're planning to buy or remortgage in the next 12-24 months, run the numbers on the affordability impact before you increase your sacrifice rate.

Statutory maternity, paternity, and adoption pay. These are calculated on average weekly earnings during a specific reference period — and sacrificed salary is not included. For someone who sacrifices heavily in the year before going on maternity leave, the SMP figure can come in noticeably lower than expected. Some employers top SMP up to full salary regardless; many do not. If you're planning to start a family, it's worth temporarily pausing or reducing sacrifice during the SMP reference period.

Death-in-service cover. Many UK employers provide death-in-service cover as a multiple (typically 2-4x) of base salary. That base salary is usually the post-sacrifice figure. On a £55,000 salary sacrificing 10%, that's around £5,500 less cover per multiple — so on a 4x policy, £22,000 of lost cover. Some schemes are written on "reference salary" instead, which protects against this; you need to read your own scheme's policy document to find out.

State pension entitlement. Salary sacrifice cannot reduce your gross salary below the National Insurance lower earnings limit (£6,708 in 2026/27) without starting to erode your qualifying year for state pension purposes. In practice this is only a risk for low earners or part-time workers with relatively small salaries and aggressive sacrifice percentages — most employers apply a floor to prevent this — but it's a real consideration for anyone working reduced hours.

Not all employers offer it. Salary sacrifice is a contractual arrangement, which means your employer has to agree to set it up and run it. Smaller employers sometimes don't bother because of the admin burden. Employers with multiple pension providers sometimes only offer sacrifice through one of them. If your workplace doesn't offer sacrifice, you're not out of luck — relief at source still works — you're just paying the NI that sacrifice would have avoided.

How to set it up at work

Salary sacrifice is a variation of your employment contract. Some employers automate the process through a benefits portal, while others require a form or payroll instruction.

The standard sequence is:

1. Check with HR or the pensions/benefits team whether salary sacrifice is available on your workplace scheme.
2. Ask for the scheme rules — specifically: does the employer pass on any of their employer NI saving, and if so how much?
3. Complete the contractual variation form (sometimes called a "salary sacrifice election" or "flex choice"). This typically asks for the amount you want to sacrifice in £ or percentage terms, and the effective date.
4. Check the next payslip. Your gross salary should show the reduced figure, and there should be a line somewhere (often labelled "employer pension contribution") showing the sacrificed amount going into the scheme. If it doesn't appear correctly on the first payslip, escalate immediately — payroll errors in the first month of a new sacrifice arrangement are common.

Many schemes operate an annual enrolment window, meaning you can only change your sacrifice percentage once a year (usually during a flex benefits window in spring or autumn). Others let you change it whenever you like. Either way, it's worth timing larger sacrifice increases to align with bonus payments or pay rises, because the biggest marginal savings are usually on top slice of income.

Slide the numbers

This is the embedded salary sacrifice calculator from our tools hub. Change the salary, the sacrifice amount, and the employer NI pass-through toggle to see your specific take-home impact and pension contribution side by side.

The calculator is designed to show the take-home impact beside the pension contribution, and how much the result changes if the employer passes on some or all of its NI saving.

Salary sacrifice versus relief at source

For many employees earning above the NI threshold, salary sacrifice produces a higher pension contribution for the same take-home cost than relief at source. That is mainly because relief at source does not recover employee NI.

There are, however, edge cases where the two are close or relief at source is actually preferable:

• Earners below the NI threshold (£12,570). If you're earning under the NI threshold, there's no employee NI to save. Salary sacrifice and relief at source can produce similar outcomes.
• Employers who don't pass on any NI saving and charge a platform or admin fee. A tiny minority of workplace schemes charge explicit management fees that differ between sacrifice and non-sacrifice members. These should be weighed against the tax saving.
• Workers preparing for a mortgage application. If a mortgage application is imminent, the effect on assessed income can matter more than the short-term tax saving.
• Workers already at or above the annual allowance. Once you hit the £60,000 annual allowance (or a lower tapered figure), additional sacrifice triggers a tax charge that eats into — and can exceed — the saving.

Outside those exceptions, salary sacrifice is often numerically stronger than relief at source, but the employment-contract and benefit effects still need checking. Our pension fees pillar guide has a parallel discussion of the other big variable in pension outcomes — what you pay inside the pot.

High-earner checks

High earners have two specific rules to watch that don't affect most savers.

The annual allowance. The standard cap on pension contributions that can receive tax relief (from all sources — employer, employee, sacrifice) is £60,000 per tax year for 2026/27. Contributions above this trigger an annual allowance charge that claws back the relief you otherwise would have received. The £60,000 figure is gross, so a £60,000 sacrifice fills it exactly with nothing left for employer contributions on top — in practice sacrificers with generous employer contributions need to leave headroom.

Carry forward. Unused annual allowance from the three previous tax years can be carried forward and used in the current year, provided you were a member of a UK-registered pension scheme during those years. For workers with irregular income or a sudden bonus year, carry forward can allow unused annual allowance from the three previous tax years to be used alongside the current year's allowance, subject to earnings, tapered allowance and scheme rules.

The taper for very high earners. Once adjusted income (broadly, taxable income plus employer pension contributions) crosses £260,000, the £60,000 annual allowance starts to taper away at a rate of £1 for every £2 over the threshold, down to a minimum of £10,000 for anyone with adjusted income over £360,000. Salary sacrifice can interact with threshold income and adjusted income in complex ways, so high earners near the taper boundary may need regulated advice.

The April 2029 £2,000 NIC cap

The November 2025 Budget announced a structural change to how salary sacrifice works for pensions: from 6 April 2029, only the first £2,000 per year of salary-sacrificed pension contributions will be exempt from National Insurance. Contributions above £2,000/year will still get income tax relief — no change there — but the NI saving (8% employee + 15% employer = up to 23% combined) will only apply to the first £2,000.

For anyone sacrificing modestly (under £2,000/year, equivalent to about £167/month), the cap is less relevant and salary sacrifice continues to work broadly as it does today. For larger salary sacrifice arrangements — high earners, late-starter catch-up, bonus-sacrifice arrangements — the maths from 2029/30 onwards is materially less favourable than the current numbers in this guide. A £20,000 sacrifice today can save a higher-rate taxpayer about £400 of employee NI above the upper earnings limit, plus up to £3,000 of employer NI if the employer passes on its full 15% saving. From April 2029, the NI saving would apply only to the first £2,000 under the announced cap.

Income tax relief on contributions is unaffected — the cap is an NI change. Salary sacrifice can still compare favourably with relief at source in some cases, but the gap narrows substantially where contributions exceed £2,000 a year.

The pension contribution rates by age guide covers forward planning around contribution levels.

FAQ

Is there a salary sacrifice pension limit? There is no separate salary sacrifice pension limit, but all pension input from all sources counts toward the £60,000 annual allowance before any taper or MPAA restriction. Employers also have to keep post-sacrifice pay above minimum wage rules and may set their own payroll limits.

Is salary sacrifice always better than relief at source? No. It is often numerically stronger for employees earning above the NI threshold and below the annual allowance because of the employee NI saving. Edge cases include workers below the NI threshold, imminent mortgage applications, statutory pay concerns, and anyone already at the annual allowance ceiling.

How much can I sacrifice? There's no specific limit on sacrifice itself, but total pension contributions from all sources (employer, employee, sacrifice) cannot exceed the £60,000 annual allowance without triggering a tax charge. Some employers cap sacrifice at a percentage of salary. And you cannot sacrifice below the NI lower earnings limit (£6,708) without putting state pension qualifying years at risk.

Does salary sacrifice affect my state pension? Only if it drops your earnings below the National Insurance lower earnings limit. That is £129 a week, or £6,708 a year, in 2026/27. Below that level, the year may stop counting as a qualifying year for state pension. For anyone earning meaningfully more than that after sacrifice, state pension entitlement is usually unaffected.

What happens to salary sacrifice during maternity leave? Statutory maternity pay is based on average weekly earnings during a specific reference period, so salary sacrifice before that period can reduce the SMP calculation. During unpaid leave, employee sacrifice may stop, while employer pension obligations depend on scheme and employment rules. See the salary sacrifice and maternity leave guide for the detailed version.

Do KIT days affect salary sacrifice pension contributions? Keeping in touch days are paid work days during maternity leave. Whether salary sacrifice applies to KIT day pay depends on the employer's payroll rules, your sacrifice agreement, minimum wage constraints and how the workplace pension scheme handles maternity leave.

Does salary sacrifice affect my mortgage? Yes — lenders typically assess affordability against your post-sacrifice gross salary, which reduces the headline income multiple they'll lend against. Some lenders will add sacrificed pension contributions back on with documentation, but most won't. If a mortgage is imminent, check with your lender before increasing sacrifice.

Can I do salary sacrifice into a SIPP? No — not directly. Salary sacrifice is contractually between you and your employer, and the sacrificed amount has to go into the employer's nominated workplace scheme. Some people compare sacrificing into the workplace scheme and later transferring old accumulated balances, but transfers need separate checks for fees, safeguarded benefits, guarantees and employer contribution effects. See our pension fees guide for the cost considerations.

What happens to my salary sacrifice arrangement if I change jobs? The arrangement ends with your employment. At your new employer, you'd need to set up a fresh sacrifice election — they might use a different pension provider, contribution structure and employer NI pass-through policy. This is a useful point to compare the new scheme's charges, employer contributions, salary sacrifice rules and investment options.

Does HMRC need to know about my salary sacrifice? No — it's handled entirely through payroll. Your P60 will show the reduced salary figure, your tax and NI are calculated on that reduced figure automatically, and no separate claim or declaration is required. If you're in the £100k-£125,140 band or subject to HICBC, the reduced adjusted net income is reflected automatically on your tax return.

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Pension Bible is an editorial publication, not a financial adviser. The information in this guide is general guidance based on publicly available tax rules for the 2026/27 tax year. Tax treatment depends on individual circumstances and may change. Scottish taxpayers have different income tax bands. For personal recommendations about your specific pension arrangement, speak to an FCA-regulated financial adviser.