Salary sacrifice pension calculator — see what you actually save
Compare your take-home before and after salary sacrifice — with the income tax saving and the NI saving shown separately, because the NI part is the bit nobody explains.
Salary sacrifice swaps salary for employer pension contributions before tax is calculated. Because your gross pay falls, you save income tax AND National Insurance — the NI saving is unique to salary sacrifice. On £45,000, sacrificing 5% (£2,250) costs just £1,620.00 of take-home: £450.00 comes back as tax and £180.00 as NI in 2025/26.
- Personal allowance
- £12,570
- Applies in
- England, Scotland & Wales supported
- Calculation
- Reduces gross pay → cuts tax and NI
Parsed as: 1257L (£12,570 allowance, England & NI)
Why salary sacrifice beats other pension routes
Every pension route gives you income tax relief. Only salary sacrifice also avoids National Insurance, because the money never counts as your pay at all. At 8% below £50,270, that’s an extra 8p kept per £1 contributed compared with a net-pay or relief-at-source scheme — on top of the 20%, 40% or 45% of tax relief everyone gets.
The result: for the same reduction in take-home pay, salary sacrifice puts more into your pot — or for the same pot contribution, it leaves more in your bank. Some employers sweeten it further by passing on part of their own 15% employer-NI saving. The calculator above shows all three moving parts separately, so you can see exactly where each pound goes.