£18,000 with £5,000 Pension Salary Sacrifice 2025-26
England & Wales · Pension salary sacrifice · 2025-26 tax year
Before vs after £5,000 salary sacrifice — 2025-26
| Item | Before sacrifice | After sacrifice | Saving |
|---|---|---|---|
| Gross / effective salary | £18,000 | £13,000 | −£5,000 |
| Income Tax | £1,086 | £86 | £1,000 |
| National Insurance | £434 | £34 | £400 |
| Net take-home / yr | £16,480 | £12,880 | £1,400 |
| Monthly take-home | £1,373 | £1,073 | £117 |
Pension salary sacrifice: what goes into your pot
| Your pension contribution (sacrifice) | £5,000/year | £417/month |
| Employer min contribution (3%) | £540/year | £45/month |
| Estimated total pension/year | £5,540/year | £462/month |
| Real cost to take-home | £3,600/year | £300/month |
Pension salary sacrifice is the most tax-efficient way to save for retirement. Your employer may also pass on their NI saving (£750/year) as an additional pension contribution — check your scheme rules.
£18,000 with £5,000 pension salary sacrifice — explained
On a £18,000 salary, sacrificing £5,000 for pension reduces your taxable earnings to £13,000. Your Income Tax drops from £1,086 to £86 (saving £1,000), and your National Insurance drops from £434 to £34 (saving £400).
The total annual saving is £1,400 (£117/month). The real cost to your take-home pay is only £3,600/year — because the tax and NI saving offsets a significant portion of the sacrifice.
Your employer also saves 15% employer NI on the sacrificed amount — £750/year. Many employers pass this saving on as an additional pension contribution or towards the cost of an EV lease.
Frequently asked questions
How much do I save with £5,000 pension salary sacrifice on £18,000?
On a £18,000 salary, sacrificing £5,000 for pension saves you £1,400 per year (£117/month) in combined Income Tax and National Insurance. Income Tax saving: £1,000. NI saving: £400.
Is salary sacrifice worth it on £18,000?
Yes — salary sacrifice is almost always beneficial if your employer offers it. On £18,000 with a £5,000 sacrifice, you save £1,400 in tax annually. Your take-home drops by only £3,600/year (not £5,000) because the tax saving offsets part of the sacrifice.
Does salary sacrifice affect my National Insurance on £18,000?
Yes — salary sacrifice reduces your National Insurance contributions because NI is calculated on your lower contractual salary. On £18,000 with £5,000 sacrifice, you save £400/year in NI. Your employer also saves 15% NI on the sacrificed amount (£750/year), which some employers pass back to employees.
What is my take-home after £5,000 pension sacrifice on £18,000?
After a £5,000 pension salary sacrifice on £18,000, your annual take-home is £12,880 (£1,073/month). Without the sacrifice, your take-home would be £16,480 (£1,373/month). The difference (£3,600/year) is the net cost to your take-home.
Does salary sacrifice affect my pension on £18,000?
For pension salary sacrifice: your pension pot grows by the full £5,000 sacrifice plus employer contributions. For EV or cycle sacrifice, your auto-enrolment pension is unaffected as it is based on qualifying earnings, not the sacrificed benefit. However, some mortgage lenders use post-sacrifice salary — confirm with your employer how they report income.
How does salary sacrifice affect State Pension on £18,000?
Salary sacrifice reduces your NI-able earnings. On £18,000 the effective salary after sacrifice is £13,000, which is well above the Lower Earnings Limit (£6,396 in 2025-26) — so your State Pension entitlement and NI record are unaffected.