£17,000 vs £21,000 After Tax 2025-26
Side-by-side UK take-home pay comparison · Income Tax + National Insurance
You keep £2,880 more per year
Earning £21,000 instead of £17,000 gives you £240 more per month (£55/week). Of the £4,000 gross difference, you keep 72% after tax and NI.
£17,000 — Income Tax bands
| Band | Tax |
|---|---|
| Personal Allowance | — |
| Basic Rate (20%) | £886 |
| Total Income Tax | £886 |
£21,000 — Income Tax bands
| Band | Tax |
|---|---|
| Personal Allowance | — |
| Basic Rate (20%) | £1,686 |
| Total Income Tax | £1,686 |
Full breakdown — £17,000 vs £21,000
| £17,000 | £21,000 | Difference | |
|---|---|---|---|
| Gross salary | £17,000 | £21,000 | +£4,000 |
| Income Tax | £886 | £1,686 | +£800 |
| National Insurance | £354 | £674 | +£320 |
| Total deductions | £1,240 | £2,360 | +£1,120 |
| Net pay (annual) | £15,760 | £18,640 | +£2,880 |
| Net monthly | £1,313 | £1,553 | +£240 |
| Net weekly | £303 | £358 | +£55 |
| Net daily | £61 | £72 | +£11 |
| Effective tax rate | 7.29% | 11.24% | |
| Marginal tax rate | 28% | 28% |
£17,000 vs £21,000 after tax — what you actually keep
On a £17,000 salary, you take home £15,760 per year (£1,313/month). On £21,000, you take home £18,640 per year (£1,553/month). The £4,000 gross difference translates to £2,880 extra take-home — you keep 72% of the raise.
Income Tax on £17,000 is £886, rising to £1,686 on £21,000. National Insurance increases from £354 to £674. Together these deductions mean HMRC takes £1,120 of the £4,000 difference.
Why the effective rate changes
At £17,000 the effective tax rate is 7.29%, while at £21,000 it rises to 11.24%. This is because additional earnings are taxed at the marginal rate (28% on £21,000), which is higher than the blended average. The more you earn, the greater the proportion taken in tax and NI.
Frequently asked questions
How much more do I take home on £21,000 vs £17,000?
On £21,000 you take home £18,640/year (£1,553/month), compared to £15,760/year (£1,313/month) on £17,000. That is £2,880 more per year, or £240 more per month.
Why is the net difference (£2,880) less than the gross difference (£4,000)?
Of the £4,000 gross difference, you keep £2,880 (72%) after Income Tax and National Insurance. The rest goes to HMRC. Your marginal rate on £17,000 is 28% and on £21,000 it is 28%.
What is the effective tax rate on £17,000 vs £21,000?
The effective tax rate (Income Tax + NI as a percentage of gross) is 7.29% on £17,000 and 11.24% on £21,000. The higher salary has a higher effective rate because more income falls into higher tax bands.
How much tax and NI do I pay on £17,000 vs £21,000?
On £17,000: Income Tax £886 + NI £354 = £1,240 total deductions. On £21,000: Income Tax £1,686 + NI £674 = £2,360 total deductions.