Don't accept an inside IR35 rate until you've run the numbers.

Two reasons. First, we use 2026/27 tax rates by default — many competitor calculators still default to 2025/26, where dividend tax was 2 percentage points lower. Second, our 220-day assumption is conservative; some calculators use 230 or 250 days, which makes the headline figures look bigger.

If your number is different, check the assumptions section above and the working day / margin defaults the other calculator is using.

Three forces converge above ~£700/day. The personal allowance fully tapers above £125,140 of total income (so your director's salary becomes taxable). Additional rate dividends (39.35%) start to apply. Corp tax effective rate climbs toward 25% as marginal relief tapers.

At £1,000/day outside, you only need £1,021/day inside to match — barely 2% more. The widely-quoted "20% uplift" rule of thumb is plain wrong at this level.

Dividend tax went up by 2 percentage points (basic 8.75% → 10.75%, higher 33.75% → 35.75%). Plan 1, 2 and 4 student loan thresholds nudged up. Everything else — personal allowance, income tax bands, employee NI, employer NI, corp tax, dividend allowance — is frozen until April 2031.

The dividend tax hike only affects outside IR35 contractors (paid via dividends). Inside IR35 contractors (paid PAYE) are unaffected. So the inside/outside gap has actually narrowed in 2026/27.

Yes — every umbrella with a pay bill above £3 million per year is liable for the 0.5% apprenticeship levy, and they all deduct it from your contract value rather than paying it themselves. Every reputable umbrella is well above that threshold. Some calculators ignore this; we don't, because it's real money you don't see on your payslip.

£12,570 is the personal allowance — the highest salary you can take with zero income tax. Above £5,000 you pay 15% employer NI, but the £1,135 of NI is far outweighed by the dividend tax saved by maxing out personal allowance against salary. It's the standard "optimal director's salary" advice for 2026/27 and our V1 sticks with it for simplicity.

V2 will let you toggle to alternative strategies (£5,000 minimum-NI salary, or custom).

This calculator uses England, Wales and Northern Ireland income tax bands only. Scottish residents pay different income tax (Starter, Basic, Intermediate, Higher, Advanced and Top rates with different thresholds), so the inside IR35 calculation will be slightly off if you're a Scottish taxpayer.

National Insurance, Corporation Tax, Employer NI, Apprenticeship Levy and Dividend Tax are UK-wide and apply identically in Scotland, so the outside IR35 figure is broadly accurate. Scottish income tax support is on the roadmap for V2.

No. This is a calculator using HMRC's published 2026/27 rates. Useful for comparing contracts, not for filing your tax return. For your specific situation, talk to a contractor accountant.