Salary sacrifice: how it works, what it saves, and what is changing in 2029
Salary sacrifice is one of the most effective ways to boost your pension while reducing your tax bill. It cuts both income tax and National Insurance on the same contribution, which is something a standard personal pension contribution cannot do. And with a significant rule change arriving in April 2029, the window to make the most of the current rules is open now.
This guide covers how salary sacrifice works, what it saves at 2026/27 rates, where it matters beyond the pension, and what the 2029 National Insurance cap means for you.
What salary sacrifice is
Salary sacrifice is an arrangement where you agree to reduce your gross salary and your employer pays the same amount directly into your pension instead. Your payslip shows a lower salary. Because your salary is lower, you pay less income tax and less National Insurance. Your employer also pays less employer National Insurance on your wages.
That last part matters. Salary sacrifice is the only way to get National Insurance relief on a pension contribution. Personal pension contributions get income tax relief but not NI relief. Salary sacrifice gets both.
With a personal pension contribution, you get income tax relief but not NI relief. With salary sacrifice, you get both. On a £1,000 contribution, that difference can be worth £80 or more depending on your earnings.
How the savings work in 2026/27
Employee National Insurance in 2026/27 runs at 8% on earnings between £12,570 and £50,270, and 2% on earnings above £50,270. Employer NI is charged at 15% on earnings above £5,000 per year. Income tax relief applies at your marginal rate, on top of these NI savings.
For a basic rate taxpayer sacrificing £1,000 within the standard NI band, the saving breaks down as £200 in income tax (20%) and £80 in employee NI (8%). The net cost to that person is £720 for £1,000 going into their pension.
For a higher rate taxpayer sacrificing £1,000 above the £50,270 upper NI threshold, the saving is £400 in income tax (40%) and £20 in employee NI (2% above the upper threshold). Net cost is £580 for £1,000 into the pension. Where that higher rate taxpayer has earnings between £12,570 and £50,270, they save the same £80 in NI as a basic rate taxpayer, making the combined saving even larger.
Employer NI: the employer saves 15% on the sacrificed amount. Some employers pass this saving on to employees as an additional pension contribution. Always worth asking your HR or payroll team, because on a £2,400 annual sacrifice that is an extra £360 that could be going into your pension at no cost to either party.
Annual sacrifice: £2,400. This sits within the 8% NI band (earnings of £45,000 are below £50,270).
Income tax saved: £480 (20% of £2,400). Employee NI saved: £192 (8% of £2,400). Total employee saving: £672 per year.
Net cost: £1,728 for £2,400 going into pension. Every £1 in pension costs £0.72 net.
Employer NI saved: £360 (15% of £2,400). If the employer passes this saving on, the pension contribution could be £2,760 for the same employee cost.
Salary sacrifice vs personal pension contributions
Both methods deliver income tax relief. The difference is National Insurance. A personal contribution to a relief at source pension comes from your take-home pay, and your pension provider claims 20% basic rate relief from HMRC automatically. If you are a higher or additional rate taxpayer, you claim the extra relief through Self Assessment. Either way, income tax relief arrives. NI relief does not.
With salary sacrifice, your gross salary is reduced before NI is calculated. That means every pound you sacrifice into your pension is a pound that was never taxed for NI purposes. For a basic rate taxpayer within the 8% NI band, salary sacrifice is worth approximately 8% more than a personal contribution of the same amount. For a higher rate taxpayer above £50,270, the extra NI saving is only 2%, but the income tax saving is the same.
If your employer offers salary sacrifice, it is almost always the more efficient route. If your employer does not offer it, personal contributions to a relief at source pension still give full income tax relief and are well worth using.
The uses beyond pension saving
Salary sacrifice reduces your adjusted net income, which is the number HMRC uses for several important calculations. Three places where this matters particularly.
First: the High Income Child Benefit Charge. The charge kicks in at £60,000 adjusted net income and withdraws Child Benefit entirely by £80,000. Salary sacrifice pension contributions reduce adjusted net income. Enough sacrifice can bring someone below the £60,000 threshold and eliminate the charge entirely. See our full guide to the Child Benefit tax charge for the detail on how the taper works.
Second: the personal allowance taper. For earnings above £100,000, the £12,570 personal allowance reduces by £1 for every £2 earned above that threshold. Salary sacrifice contributions that bring adjusted net income to or below £100,000 recover the full allowance, effectively avoiding an effective marginal rate of around 60% in that band.
Third: Tax-Free Childcare. Eligibility requires adjusted net income below £100,000 per parent. Salary sacrifice pension contributions count toward reducing this figure, so they can be the deciding factor in whether a family qualifies.
All three of these thresholds use adjusted net income, not gross salary. Salary sacrifice pension contributions reduce adjusted net income directly. This makes them one of the most powerful planning tools for people near these thresholds.
What is changing from April 2029
From April 2029, only the first £2,000 of employee pension contributions via salary sacrifice per year will be exempt from National Insurance contributions. Contributions above that level will attract employee NI at the standard rates. Income tax relief is not affected by this change. Employer pension contributions outside salary sacrifice also remain NI exempt.
For most employees on typical auto-enrolment rates, the cap will make no difference. Someone contributing £100 per month (£1,200 per year) is below the £2,000 cap and sees no change at all. Someone contributing £300 per month (£3,600 per year) will pay NI on £1,600 of their contributions from April 2029.
The April 2029 change is a National Insurance change only. Income tax relief on salary sacrifice pension contributions is unchanged. If your contributions are below £2,000 per year, you will not notice any difference.
| Monthly contribution | Annual | Below 2029 cap | NI owed from 2029 (basic rate) | Impact |
|---|---|---|---|---|
| £83/mo | £1,000 | Yes (under £2,000) | £0 | No change |
| £167/mo | £2,000 | Yes (at cap) | £0 | No change |
| £250/mo | £3,000 | No (£1,000 above cap) | £80/yr | Small |
| £417/mo | £5,000 | No (£3,000 above cap) | £240/yr | Moderate |
| £500/mo | £6,000 | No (£4,000 above cap) | £320/yr | Worth noting |
What to do now
2026/27 and 2027/28 are the last two full tax years before the cap arrives. If you have been considering increasing salary sacrifice contributions, doing so now means two full years at the current NI-exempt rate before anything changes. That is a meaningful window for anyone who has been on the fence.
The change does not affect contributions below £2,000 per year. If you are at typical auto-enrolment levels, the April 2029 change is not a reason to act urgently. If you are a higher earner near the High Income Child Benefit Charge threshold or the £100,000 personal allowance taper, the window before 2029 is worth using to put more into the pension while the full NI exemption applies.
Calculate your salary sacrifice saving
Enter your salary and monthly contribution to see your income tax saved, NI saved, net cost, and how the 2029 cap will affect you.
Limitations to know
Three things worth checking before you increase salary sacrifice contributions.
Salary sacrifice cannot reduce pay below the National Minimum Wage. This is a legal requirement and your employer cannot set up an arrangement that would breach it. If your salary is close to the minimum wage, your employer may not be able to offer a salary sacrifice arrangement at all, or may cap it below your preferred level.
A lower gross salary may affect mortgage applications, where affordability is typically assessed on basic salary. If you are planning to apply for a mortgage or remortgage in the next year or two, it is worth discussing with your broker before changing your contribution level. Some lenders will take pension contributions into account, but practices vary.
Statutory Maternity Pay and Statutory Paternity Pay are calculated based on earnings. Salary sacrifice reduces the earnings figure, which can reduce statutory pay. Worth checking with your employer before increasing contributions significantly if you are planning a family in the near term.