Locum tax basics for UK doctors
A practical overview of self-assessment, allowable expenses, and what to track throughout the tax year as a locum doctor.
- tax
- self-assessment
- expenses
Working as a locum usually means you are self-employed (or a combination of employed and self-employed). That brings flexibility — and a few extra admin responsibilities.
Self-assessment
Most locums need to register for Self Assessment with HMRC and file a tax return each year. Deadlines and payment dates matter; missing them can mean penalties.
If you are new to locuming, register early rather than waiting until January pressure hits.
What to track
Keep a clear record of:
- Session fees and dates
- Mileage between home and practices (where allowable)
- Parking, tolls, and other travel costs
- Professional subscriptions and indemnity
- Equipment and software used for work
Tools like LocumBook help you capture sessions and mileage as you go, so January is a summary exercise rather than a reconstruction project.
Allowable expenses
Not every cost is allowable. Rules depend on your circumstances, and this is not personal tax advice. When in doubt, check HMRC guidance or speak to an accountant who understands medical locum work.
Next steps
- Log sessions promptly after each shift
- Keep receipts and mileage notes
- Review your year-to-date position before the tax year ends
For day-to-day tracking in the app, see the user manual.
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- Home-to-practice mileage — when it actually counts
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