£45,000 Salary — 15% Pay Rise After Tax

A 15% pay rise from £45,000 to £51,750 adds £6,750 to your gross pay. After income tax and National Insurance, you keep £4,652/year (£388/month) extra.

Gross pay rise
£6,750
15% increase
Extra take-home/year
£4,652
Extra take-home/month
£388
Marginal tax rate
0.31081481481481477%

Before vs after — annual figures 2025-26

Before (£45,000) After (£51,750) Change
Gross salary £45,000 £51,750 +£6,750
Income Tax −£6,486 −£8,132 −£1,646
National Insurance −£2,594 −£3,046 −£452
Take-home/year £35,920 £40,572 +£4,652
Take-home/month £2,993 £3,381 +£388
Effective tax rate 20.18% 21.6%

England 2025-26 rates. Personal Allowance £12,570. See Scotland for Scottish income tax.

Why you keep less than 15% of your pay rise

A 15% pay rise of £6,750 sounds significant, but the effective marginal tax rate on this additional income is 0.31081481481481477% — meaning you only keep £4,652 of the £6,750 increase.

The marginal rate combines income tax (20% or 40% depending on your band) and employee NI (8% on earnings between £12,570 and £50,270, 2% above). A pay rise that pushes you into the higher rate band (above £50,270) will be taxed at 42% on the portion above that threshold.

Calculate your exact take-home pay

£
← £42,000 + 15% £48,000 + 15% →

Understanding your pay rise after tax

When you receive a 15% pay rise from £45,000 to £51,750, the £6,750 increase in gross pay does not translate directly into more take-home pay. Income Tax and National Insurance are deducted from the additional earnings at your marginal rate — the rate that applies to the top slice of your income.

For most employees earning between £12,570 and £50,270, the marginal rate is 28%: 20% income tax plus 8% employee NI. Above £50,270, NI drops to 2% but income tax rises to 40%, giving a marginal rate of 42%. If your pay rise takes you over the £50,270 threshold, the portion above it is taxed at 42% rather than 28%.

If you want to maximise the benefit of your pay rise, consider salary sacrifice into a pension — contributions made this way reduce your taxable pay, effectively giving you the full gross value of part of your rise tax-free. You can also use a pension calculator to model the long-term impact.

Related calculators:

£51,750 After Tax £45,000 After Tax Salary Sacrifice Pension Calculator Income Tax Rates National Insurance