MTD for Locum Opticians —
Day Rates, Agencies and Your Threshold
Only include genuinely self-employed locum days. PAYE shifts through an umbrella or practice payroll don't count towards this threshold.
- Only genuinely self-employed locum days count towards your MTD threshold. PAYE shifts (including through an umbrella company) are excluded entirely.
- The same £50k / £30k / £20k phased thresholds apply as any other self-employed sole trader.
- Mileage between practices, GOC fees, professional indemnity insurance and CET course costs are all standard allowable expenses under MTD.
If you work as a self-employed locum optician or optometrist, covering shifts across independent practices, multiples, or via a locum agency, Making Tax Digital applies to you the same way it applies to any self-employed sole trader. The detail that actually matters is working out which of your locum days are genuinely self-employed, since locum work is booked in several different ways that are taxed very differently.
Are You Affected by MTD as a Locum Optician?
Yes, if your gross genuinely self-employed locum income, plus any other self-employment or rental income, exceeds the relevant threshold:
| Tax Year Assessed | Threshold | MTD Start Date |
|---|---|---|
| 2024–25 | Over £50,000 | 6 April 2026. Live since April 2026 |
| 2025–26 | Over £30,000 | 6 April 2027 |
| 2026–27 | Over £20,000 | 6 April 2028 |
Your gross income is your total day-rate fees received before expenses, not your take-home after mileage, GOC fees or insurance. A locum working three to four days a week at a typical day rate can reach the £50,000 threshold comfortably across a full year.
Self-Employed, Umbrella, or Limited Company — Which Bookings Count?
Locum optical work is booked in several different ways, and only one of them counts towards your MTD threshold:
- Directly self-employed, invoicing the practice or agency yourself as a sole trader — this counts in full towards your MTD threshold
- Umbrella company PAYE, where an umbrella company employs you and pays you a wage after deductions — this is employment income and does not count towards MTD, regardless of how the booking is described
- Through your own limited company, company profits sit outside MTD for Income Tax entirely, which only reaches sole trader and property income
Booking Through an Agency vs Direct to Practice
Whether you're booked through a locum agency or arrange shifts directly with practices makes no difference to your MTD position, provided the engagement itself is genuinely self-employed. What matters is the substance of the arrangement (are you invoicing for your services, controlling your own hours and using your own indemnity cover), not which route the booking came through.
What You Can Claim
| Expense Category | Examples |
|---|---|
| Professional registration | GOC annual retention fee |
| Professional indemnity insurance | Cover arranged independently or via a professional body |
| CET and CPD | Continuing education points required for GOC revalidation |
| Mileage | Travel between practices, at the current HMRC mileage rate |
| Equipment | Personal instruments not provided by the practice, via capital allowances if significant |
Records for Locum Days, Agencies and Practices
Locum opticians work across practices and agencies, with day rates and sometimes commission on dispensing. A per-day log is the cleanest record.
- Log each day: practice, date, rate, invoice number and payment date.
- Tag each day invoiced or payslip.
- Record GOC registration, indemnity and CPD costs.
- Keep equipment, instruments and software costs.
- Keep mileage between practices.
A Sample Quarter: What the Update Looks Like
A sample quarter for a locum with two main practices and some agency days.
| Q2: 6 July to 5 October 2026 | Amount |
|---|---|
| Locum days invoiced to practices | £14,800 |
| Agency days paid gross | £3,600 |
| Total income | £18,400 |
| GOC, indemnity and CPD | £520 |
| Mileage | £1,150 |
| Equipment and instruments | £330 |
| Accountancy and software | £280 |
| Total expenses | £2,280 |
| Profit for the quarter | £16,120 |
Days paid through a payslip would not be in this table, because they are employment income.
Worked Example
Sana — Self-employed locum optometrist, mixed bookings
Sana's umbrella PAYE shifts are already taxed at source and excluded entirely. Only her £51,000 of genuinely self-employed bookings counts, which puts her just above the £50,000 Phase 1 threshold.
Frequently Asked Questions
Do umbrella company shifts count towards my MTD threshold?
No. If an umbrella company employs you and deducts tax and National Insurance before paying you, that's employment income, not self-employment, and it doesn't count towards your MTD threshold regardless of how the booking was described.
What's the MTD threshold for locum opticians?
The same as any self-employed sole trader: over £50,000 genuinely self-employed gross income in 2024–25 means MTD from April 2026, over £30,000 in 2025–26 means April 2027, over £20,000 in 2026–27 means April 2028.
Does it matter if I book locum work through an agency or directly with practices?
No, provided the engagement itself is genuinely self-employed. The booking route doesn't change your tax position, what matters is whether you're invoicing for your services and controlling your own working arrangement, not the intermediary.
Can I claim my GOC fee and indemnity insurance as expenses?
Yes. GOC registration fees, professional indemnity insurance, and CET or CPD course costs required for revalidation are all standard allowable expenses for a self-employed locum optician.
How do I know if a booking is self-employed or PAYE?
Check your remittance or booking confirmation. If tax and National Insurance are already deducted before you're paid, it's PAYE. If you're invoicing gross and responsible for your own tax, it's self-employed.
What software do I need as a locum optician?
Any HMRC-recognised MTD software works. There's no optician-specific requirement, the main need is separating genuinely self-employed income from any umbrella PAYE shifts, which is a simple categorisation task in any standard software.
Check Your Full MTD Position
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