Resident doctors on the 2016 and 2002 contracts, specialty doctors and the specialist grade on the 2021 terms, and consultants on the 2003 contract. Full-time and less than full-time. It reads ESR payslips, which is what NHS England and NHS Wales use.

Partly, and it tells you where it does not. Scottish income tax has its own bands and those are applied for 2022/23 to 2025/26; a Scottish code in a year without a loaded band table is flagged rather than estimated. Northern Ireland runs on a different payroll system to ESR, so those payslips are not read reliably yet. Wales uses ESR and the same tax rates as England, so it is covered.

Not yet. Agency and umbrella payslips have a different structure from an ESR payslip, and the app will tell you it cannot read one rather than guessing at the figures. Your NHS trust payslips — substantive and bank — read normally, and those are the ones the pay circular and your contract apply to.

If you do agency work it is still worth adding your trust payslips: the tax checks work across everything you have been paid, and agency income is part of the same personal allowance.

Published sources only — the Pay and Conditions Circulars, HMRC's rates and thresholds, and the NHS Pension Scheme member contribution tiers. Every document is listed on the reference data page, with what it governs, when it was last verified, and what is deliberately not loaded.

Rates are held from 2022/23 onwards, which is the four-year window for reclaiming overpaid tax. Older payslips can still be read; there is simply nothing loaded to check them against.

Yes, and that is where most of what it finds lives. Two employments each get a personal allowance from a payroll that cannot see the other, and above £100,000 the allowance tapers away. Add every post you have.

A photograph works. Lay the payslip flat, fill the frame, keep the light even. The PDF from ESR reads more reliably where you have it, and on a computer you can take a screenshot the usual way and paste it straight in with Ctrl+V.

Every payslip is checked against its own printed totals — the pay lines must add up to total payments, the deductions to total deductions, and the difference to net pay. If they do not, the slip is flagged and you are told which figure to look at. It would rather query a payslip than quietly report a wrong number.

Yes — a folder, a zip, or a pile of photographs. Duplicates are set aside automatically rather than counted twice.

Nowhere. Every check runs inside the page, in your own browser. Nothing is uploaded, there is no account, and no server holds your pay history — because there is no server. See the privacy notice.

One thing, and only if you hold a subscription: a licence id, so the app can ask whether that subscription is still running. No name, no email, nothing off a payslip.

They are ignored outright. The assignment number is read only to tell separate posts apart — bank work from your substantive job — and never leaves the page.

No. It is a checking tool. It shows you the arithmetic and the rule it relied on so you can judge for yourself, and it is independent of the NHS, ESR and HMRC.

The app writes the letter. A wrong pay figure is payroll's; a wrong tax code is HMRC's — two different problems with two different recipients, and it drafts to whichever applies, citing the exact figure and the rule.

Usually the opposite: under-collected tax is money owed to HMRC, not to you. It is normally recovered through a later tax code, and the value of knowing early is that you can have the code corrected before the shortfall builds.

Yes — a report of the findings, the year-by-year position, and any payslips missing from the analysis. You can see exactly what it says before you print it.