£100,000 with £4,000 Pension Salary Sacrifice 2025-26
England & Wales · Pension salary sacrifice · 2025-26 tax year
Before vs after £4,000 salary sacrifice — 2025-26
| Item | Before sacrifice | After sacrifice | Saving |
|---|---|---|---|
| Gross / effective salary | £100,000 | £96,000 | −£4,000 |
| Income Tax | £27,432 | £25,832 | £1,600 |
| National Insurance | £4,011 | £3,931 | £80 |
| Net take-home / yr | £68,557 | £66,237 | £1,680 |
| Monthly take-home | £5,713 | £5,520 | £140 |
Pension salary sacrifice: what goes into your pot
| Your pension contribution (sacrifice) | £4,000/year | £333/month |
| Employer min contribution (3%) | £3,000/year | £250/month |
| Estimated total pension/year | £7,000/year | £583/month |
| Real cost to take-home | £2,320/year | £193/month |
Pension salary sacrifice is the most tax-efficient way to save for retirement. Your employer may also pass on their NI saving (£600/year) as an additional pension contribution — check your scheme rules.
£100,000 with £4,000 pension salary sacrifice — explained
On a £100,000 salary, sacrificing £4,000 for pension reduces your taxable earnings to £96,000. Your Income Tax drops from £27,432 to £25,832 (saving £1,600), and your National Insurance drops from £4,011 to £3,931 (saving £80).
The total annual saving is £1,680 (£140/month). The real cost to your take-home pay is only £2,320/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 — £600/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 £4,000 pension salary sacrifice on £100,000?
On a £100,000 salary, sacrificing £4,000 for pension saves you £1,680 per year (£140/month) in combined Income Tax and National Insurance. Income Tax saving: £1,600. NI saving: £80.
Is salary sacrifice worth it on £100,000?
Yes — salary sacrifice is almost always beneficial if your employer offers it. On £100,000 with a £4,000 sacrifice, you save £1,680 in tax annually. Your take-home drops by only £2,320/year (not £4,000) because the tax saving offsets part of the sacrifice.
Does salary sacrifice affect my National Insurance on £100,000?
Yes — salary sacrifice reduces your National Insurance contributions because NI is calculated on your lower contractual salary. On £100,000 with £4,000 sacrifice, you save £80/year in NI. Your employer also saves 15% NI on the sacrificed amount (£600/year), which some employers pass back to employees.
What is my take-home after £4,000 pension sacrifice on £100,000?
After a £4,000 pension salary sacrifice on £100,000, your annual take-home is £66,237 (£5,520/month). Without the sacrifice, your take-home would be £68,557 (£5,713/month). The difference (£2,320/year) is the net cost to your take-home.
Does salary sacrifice affect my pension on £100,000?
For pension salary sacrifice: your pension pot grows by the full £4,000 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 £100,000?
Salary sacrifice reduces your NI-able earnings. On £100,000 the effective salary after sacrifice is £96,000, which is well above the Lower Earnings Limit (£6,396 in 2025-26) — so your State Pension entitlement and NI record are unaffected.