Do locum pharmacists pay tax through Self Assessment?

A self-employed locum does. Income is reported on a Self Assessment return each year, with the £12,570 personal allowance applied before income tax at 20%, 40% and 45%.

Should a locum use a limited company?

It depends on the numbers. A company pays corporation tax at 19% up to £50,000 of profit and 25% above £250,000, and adds administration, so it suits some locums and not others.

Who decides IR35 status?

For medium and large clients, the client decides. For small clients, the worker's own company assesses its status for each engagement.

Locum Pharmacist Tax Explained

Written and reviewed by the Pharmacy Accountants editorial team. Last reviewed 28 July 2026.

A locum pharmacist can be taxed in more than one way, and the label on the shift does not settle it. Whether you are self-employed, employed for the day, or working through your own company changes how tax is calculated, when it is due, and what you can claim.

This guide explains the options and the rules that decide which one applies. If you would rather hand the return itself to someone, our accountants for locum pharmacists prepare and file it for you.

Self-Employed vs Employed Locum Work

A genuinely self-employed locum runs a trade and reports income through Self Assessment. An employed locum is on a payroll, with tax and National Insurance deducted at source under PAYE. The same person can be both across different engagements in a single year, and each source is taxed on its own footing.

Sole Trader vs Limited Company

A self-employed locum can trade as a sole trader or through a limited company. A sole trader is taxed personally on profits. A company pays corporation tax at 19% on profits up to £50,000 and 25% above £250,000, and money is then drawn out as salary or dividends. The company route adds administration, so it earns its place on the numbers rather than by default.

Off-Payroll Working and IR35

Where a locum works through their own limited company, the off-payroll rules, known as IR35, ask whether the engagement looks like employment. For medium and large clients the client determines status. For small clients the worker's own company assesses it. The guidance on off-payroll working sets out who decides, and getting it wrong moves the tax bill, so status is checked engagement by engagement.

The Self Assessment Return

A self-employed locum reports profit on a Self Assessment return each year. Profit is income less allowable expenses, and the personal allowance of £12,570 applies before income tax at 20%, 40% and 45% on the bands above it. Professional fees and subscriptions can be claimed against tax where they qualify. Knowing which costs reduce profit is the other half of the job, and we set them out in pharmacist expenses and allowances.