Adjust the inputs above and press Calculate to see your personalised result.
What is HCAS, and why it isn't a simple percentage
High Cost Area Supplement (HCAS) — often called London weighting — tops up NHS Agenda for Change pay for staff whose trust is in or near London. There are three zones for 2026/27: Inner London 20%, Outer London 15% and London Fringe 5%. But the headline percentage is only half the story, because each zone has a minimum and a maximum.
The supplement is clamp(basic × rate, floor, ceiling). Lower bands get floored up to the minimum; higher bands get capped down to the maximum. Only the middle bands actually receive their flat percentage.
| Zone | Rate | Minimum | Maximum |
|---|
| Inner London | 20% | £5,794 | £8,746 |
| Outer London | 15% | £4,870 | £6,137 |
| London Fringe | 5% | £1,346 | £2,270 |
Worked example 1 — hitting the floor (Band 2, Inner London)
A Band 2 employee on £25,272 in Inner London: 20% is £5,054, which is below the £5,794 floor, so the supplement is floored up to £5,794. Pensionable pay becomes £31,066, landing in the 8.3% pension tier. The lowest-paid staff therefore get a proportionally larger boost than the flat 20% implies.
Worked example 2 — the flat rate (Band 5, Inner London)
A Band 5 nurse on £32,073: 20% is £6,415, comfortably inside the £5,794–£8,746 band, so they receive the full percentage. But HCAS is taxable, National-Insured and pensionable, so the net uplift is about £3,731 — roughly 58% of the gross supplement. That is the number payroll actually adds to their take-home.
Worked example 3 — hitting the ceiling (Band 8a, Inner London)
A Band 8a manager on £57,528 in Inner London: 20% would be £11,506, but that is above the £8,746 ceiling, so the supplement is capped at £8,746. Senior staff get a smaller proportional uplift than juniors — the opposite of what a flat percentage suggests.
Two things generic calculators miss: HCAS is pensionable (so it can raise your NHS pension tier), and it is set by your trust's location, not your postcode. Both change the real-world number materially.
Change the band and zone in the calculator to see your own floor/ceiling result. For the full band-by-band picture use the NHS take-home pay hub, and for nights and weekends the NHS unsocial hours calculator.
Source: NHS Agenda for Change Terms & Conditions Handbook, Annex 8 (HCAS), and the 2026/27 NHS pay circular. HCAS figures verified 19 August 2026.
Frequently Asked Questions
Is HCAS pensionable?
Yes. High Cost Area Supplement is added to basic pay before the NHS pension is calculated, so it is fully pensionable — and because the pension tiers are non-marginal, HCAS can push you into a higher contribution tier. It is also taxable and subject to National Insurance, so the net uplift is smaller than the headline supplement.
Do I get HCAS if I live in London but work outside the zone?
No. HCAS is determined by the location of your employing trust, not where you live. If your trust sits outside the Inner, Outer or Fringe zones you get no supplement, even if you commute in from London. Conversely, if your trust is in the zone you receive HCAS even if you live well outside London.
What if my 20% is below the minimum?
Then you receive the minimum. HCAS is clamped: for Inner London the supplement is at least £5,794 and at most £8,746. A Band 2 employee whose 20% works out at about £5,054 is floored up to £5,794. Higher bands hit the ceiling instead — a Band 8a's 20% of roughly £11,506 is capped down to £8,746.
How much is NHS Inner London weighting worth after tax?
The gross supplement for a typical Band 5 in Inner London is about £6,415, but because it is taxed, National-Insured and pensionable, the net uplift is roughly £3,731 — about 58% of the gross. The exact figure depends on your band, because tax, NI and the pension tier all interact.
How does part-time work affect HCAS?
Both the supplement and the floor/ceiling are pro-rated by your whole-time equivalent (WTE). A 0.5 WTE employee in Inner London has their supplement and the £5,794–£8,746 caps halved. Enter your WTE percentage in the calculator to see the pro-rated figure.
Which zone am I in?
Inner London covers most central London trusts, Outer London the surrounding boroughs, and Fringe a ring of towns just outside Greater London (parts of Hertfordshire, Essex, Surrey, Kent and Berkshire). Your trust's HR or payslip states your HCAS zone; the authoritative list is in the AfC Terms & Conditions Handbook, Annex 8.