Day rate and days worked in, take-home out: income tax, Class 4 National Insurance and the amount to set aside every month on 2026/27 rates — plus whether your gross turnover puts you inside Making Tax Digital, which is measured on turnover rather than profit.
What you invoice for a standard day, excluding VAT if you are registered.
Actual days you expect to work and invoice. Take out holiday, study leave and the weeks nobody books you.
RCVS registration, your own professional indemnity insurance, travel between engagements, CPD, instruments, accounting and software.
Illustrative figures on 2026/27 rates and simplified assumptions. This is information, not advice, and it is no substitute for a proper calculation on your practice's real numbers. Ask us for the accurate version — it's free.
We will send the figures exactly as they appear on the right, so you have them when you sit down with your partners, your practice manager or your bank. We use your address for that and for the monthly veterinary practice finance email, nothing else, and you can unsubscribe from the first one you get.
These are 2026/27 rates for England, Wales and Northern Ireland, on the assumption that you are self-employed as an individual rather than working through a company. Income tax runs at 20% on the first £37,700 of taxable income, 40% from £37,701 to £125,140 and 45% above that, with a personal allowance of £12,570 that tapers away by £1 for every £2 of income over £100,000. Those thresholds are frozen until 5 April 2031, so a rising day rate pushes more of your income into the higher bands every year without any rate changing.
Class 4 National Insurance is charged on your profits at 6% between £12,570 and £50,270 and 2% above £50,270. Stack income tax and Class 4 and the marginal cost of the next pound of profit is 42% above £50,270 and 47% above £125,140. Class 2 National Insurance is voluntary at £3.65 a week, and profits above the Small Profits Threshold of £7,105 give you the National Insurance credit without paying anything — so paying it voluntarily only makes sense if your profits fall below that threshold and you want to protect your contribution record.
The set-aside figure is the whole liability divided by twelve. Treat it as money that has already gone. Payments on account are due on 31 January and 31 July, each normally half of the previous year's liability once that liability exceeds £1,000, which means a locum whose day rate or days worked have gone up is always chasing a bigger number than the one they reserved for.
Making Tax Digital for Income Tax is measured on qualifying income, which is gross income from self-employment and property before any allowances or expenses. It is your turnover, not your profit — which is why a locum can be comfortably inside the regime on a profit that looks nowhere near the threshold. Mandation began on 6 April 2026 for qualifying income over £50,000 tested on the 2024/25 return, extends to over £30,000 from 6 April 2027 tested on 2025/26, and to over £20,000 from 6 April 2028 tested on 2026/27. Roughly 780,000 individuals are in the first tranche.
The quarterly updates are due on 7 August, 7 November, 7 February and 7 May, and the periods are cumulative from 6 April rather than being discrete quarters: 6 April to 5 July, 6 April to 5 October, 6 April to 5 January, then the full year to 5 April. Each update restates the year to date, so a correction carries forward instead of needing an amendment to an earlier submission. Updates can be sent from the end of the period up to the deadline, and up to ten days early if you expect no further transactions. A final declaration then replaces the tax return.
One structural point that follows from all of that: a locum operating through a limited company is out of scope for Making Tax Digital for Income Tax entirely, because it applies to sole traders and landlords rather than to companies. That is a genuine consideration in the structure question, though a long way from the only one — the incorporation calculator does the arithmetic and locum vet accounts covers the rest. Exemptions from Making Tax Digital do exist, including on grounds of digital exclusion.
Costs you incur wholly and exclusively for your locum work. For a locum vet the recurring ones are your RCVS registration — £431 for 2026–27, due on or before 30 April, rising to £468 if paid between 1 and 31 May and with removal from the Register if unpaid by 31 May — professional indemnity insurance in your own name, travel between engagements, continuing professional development and its associated travel, your own clinical instruments, and the cost of accounting and software.
The insurance one deserves emphasis because it is the single most useful practical point for a locum. The RCVS Code requires all your professional activities to be covered, and its guidance warns locums specifically that although the host practice's insurance is likely to provide cover for negligence claims, it may not provide any other type of cover. Representation at an RCVS concerns investigation is the obvious gap. Six practices in a quarter means relying on six policies you have not read.
What you will not find here is a list of things that might be allowable in some circumstances. The commercial conventions of locum work — agency against direct engagement, day-rate norms, notice, mileage and accommodation practice — are not documented in any primary source, so anyone quoting you profession-wide figures has made them up.
It models income tax and Class 4 National Insurance on your locum profit and nothing else. It does not model student loan repayments, other income, pension contributions, gift aid, capital gains, the High Income Child Benefit Charge, or the payments on account that will land on 31 January and 31 July — all of which move the answer, some of them a long way. It also assumes you are taxed as a sole trader, so if a practice engaging you is medium or large and has issued a Status Determination Statement putting you inside the off-payroll rules, the fee-payer is already deducting PAYE and this is not your position. Which regime applies turns on the size of the practice, not on anything about you: see IR35 for locum vets. For the accurate version on your own figures, ask us.
These tools use sensible simplifications. A free conversation gets you the accurate version — and usually two or three things worth fixing before your year end.
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