At £120,000 you’re in the strangest zone in UK personal tax. You’re deep inside the 62% marginal trap on the last £20,000 of your pay, close enough to the £125,140 additional-rate threshold that a bonus can push you out of the trap and into a lower marginal rate, and your Personal Allowance is a shredded £2,570. This guide is the honest version: what £120k pays as take-home in 2024/25, why the taper zone feels so much worse than the headline income tax suggests, and the two sacrifice numbers most people at this level end up choosing.

⚡ Just want the number? Run £120,000 through our £100k Trap Calculator — you’ll get your personal ANI, marginal rate and the exact escape sacrifice in about 10 seconds. Free, no signup.

The headline number: £120,000 gross → £76,157 net (2024/25, no pension)

ItemAmount
Gross salary£120,000
Personal Allowance (tapered)£2,570 (shrunk from £12,570 by £10,000 of taper)
Income Tax£39,432
Employee NI (Class 1)£4,411
Take-home (net)£76,157
Effective tax rate36.5%

You’re now £20,000 into the £100k–£125,140 taper zone, which has cost you £10,000 of Personal Allowance. That’s £4,000 of extra Income Tax the average payslip calculator does not show you — buried inside the “£39,432 Income Tax” line as if it were normal higher-rate tax.

The 62% zone: where £120k really hurts

Every extra pound of pay between £100,000 and £125,140 of Adjusted Net Income is taxed at:

  • 40p Income Tax (higher-rate band)
  • +20p effective, because 50p of Personal Allowance disappears and that 50p was previously tax-free but is now taxed at 40% (0.5 × 40p = 20p)
  • +2p Employee NI (upper-band)

Total: 62p on every extra £1. This is why a bonus at £120k feels so uneven vs one at £80k. On a £5,000 bonus at £80k salary you take home about £3,150 (37% marginal). On the same £5,000 bonus at £120k salary — dropped straight into the 62% zone — you take home £1,900. Same bonus, £1,250 less in the bank.

Above £125,140 the taper is finished and the additional-rate band kicks in. Additional rate is 45% + 2% NI = 47% marginal — a full 15 percentage points better than the trap zone you just left. This is the only place in the UK tax code where a pay rise moves you into a lower marginal bracket.

The £120k child-benefit picture

Two separate hits at £120k if you have kids:

  • High Income Child Benefit Charge (HICBC) — completely gone. Fully clawed back from £80,000 onwards. No amount of sacrifice at £120k gets you close to recovering it (you’d need to sacrifice ~£40,000 down to £80k).
  • Tax-Free Childcare (TFC) — £2,000/child/year, completely gone at £100k+ ANI. But this one is recoverable. Sacrificing back below £100k restores full eligibility. If you have two kids in nursery, that’s £4,000 of vouchers on the line.

At £120k with two kids, sacrificing £20,500 to hit £99,500 ANI is often the highest-return move in your entire personal finance stack.

Escape option 1: sacrifice £20,500 back to £99,500

The classic “get out of the trap” move.

MoveAmount
Salary sacrifice£20,500
Reduction in take-home£7,890
Effective personal cost per £138p
Personal Allowance restored£10,000 (from £2,570 back to £12,570)
Direct tax + NI saved£12,610
Tax-Free Childcare preservedup to £2,000/child/year

You’re putting £20,500 into your pension for £7,890 personal cost. Adding back TFC for two kids brings that effective cost down to £3,890 net — an 81% return on a pension contribution before market growth. Nothing else in UK personal finance touches this at this income.

The trade-off: your mortgage borrowing capacity drops significantly. Most lenders use gross salary, so £120k → £99,500 shrinks your borrowing limit by ~£82,000 at 4× multiple. If you’re planning to buy in the next 12 months, defer.

Escape option 2: sacrifice £5,000 to £115,000

For those who don’t want to give up the take-home fully but want the “trap tax” damage limited:

MoveAmount
Salary sacrifice£5,000
Reduction in take-home£1,900
Effective personal cost per £138p
Personal Allowance partially restored£2,500 (from £2,570 to £5,070)
Direct tax + NI saved£3,100

You stay in the trap zone but shift £5k of taxable income from the 62% band into your pension. £5,000 into the pot for £1,900 cost. It doesn’t preserve TFC but it does turn 62p-per-£1 tax into 38p-per-£1 cost. Very common move for people who want ISA contributions or emergency fund building in parallel.

The counter-intuitive third option: “let it run to £125k”

At £120,000 with a stable £15,000 bonus incoming, one option some earners consciously take is to let it run — accept the trap tax on that final £5,140, and land at £125,140 where the marginal rate drops to 47%. The intuition: if you’re planning to be well over £125,140 within 1-2 years anyway (senior career track, tech RSU vesting, etc.), the taper zone is a temporary phase and Personal Allowance won’t come back regardless.

Rough maths: £5,140 above £120k, at 62% costs £3,187 in tax. Above £125,140 you’re back on the “normal” additional-rate track. If your 3-year trajectory is £150k+, temporary trap tax may just be the cost of career progression.

When you should NOT sacrifice at £120k

  1. Mortgage plans in next 12 months. Lenders use gross salary. Sacrifice reduces your borrowing multiple more than the tax saving justifies for most first-time or moving buyers.
  2. Cash cushion is thin. Emergency fund and short-term goals come first. Sacrifice is one-way.
  3. You’re near the Annual Allowance (£60k). Employer match + previous sacrifices + carry-forward can hit the limit fast at £120k+. Above the AA, tax relief reverses.
  4. You’re leaving the UK. Overseas transfer complexity, potential LTA charge, and you’ll pay tax again on drawdown.

For most PAYE earners at £120k who plan to stay UK-tax-resident and don’t need mortgage borrowing this year, escape option 1 (sacrifice back to £99,500) is the highest-value move in the personal finance playbook. Even with no kids the direct tax saving is £12,705 on £20,500 sacrificed (62% return before growth).

Do the maths on your exact £120k

The generic numbers above assume standard tax code, no bonus, no bank interest, no dividend income, no student loan. Your real Adjusted Net Income depends on all of those, and two people with the same £120k gross can have wildly different ANI numbers.

FAQ

Is £120k inside or outside the additional-rate band? Neither. The additional-rate threshold is £125,140. At £120,000 you’re still in higher-rate territory but crushed by the Personal Allowance taper. The additional rate starts £5,140 higher — a very odd feature of the code where crossing that line actually reduces your marginal rate from 62% to 47%.

Does the 62% rate apply to Scottish taxpayers at £120k? No — Scotland has its own bands. A Scottish taxpayer at £120k on the equivalent salary hits the “advanced rate” (45%) plus the taper effect, giving an effective marginal rate around 69.5%. See our Scottish take-home calculator.

What if I have RSU or LTIP vesting on top of my £120k? RSU vests are taxable as employment income in the year they vest, and count toward ANI. This is the single biggest reason mid-career tech earners land in the trap unexpectedly — headline salary might be £120k but vest-year ANI can be £160k+. Sacrifice targets need to be sized against the total, not the base.

Can I use carry-forward to sacrifice more than £60k in a year? Yes if you had unused Annual Allowance in the previous three tax years. This is very useful at £120k+ if your employer runs a big employer-match scheme (e.g. 15% employer contribution + your sacrifice can easily blow past £60k gross into pension). Carry-forward can allow £120k+ into pension in a single year without triggering the AA charge.

When does the trap zone move with the 2025/26 rates? The £100k taper threshold and £125,140 end-of-taper are legislated as fixed figures until at least April 2028 (fiscal drag policy). Every wage inflation pushes more people into the zone. That’s part of why this problem is growing.