The 7 August 2026 deadline is approaching, and if you're self-employed — including as a locum doctor — it will mark the first ever MTD quarterly submission deadline in history. Nobody has done this before. There are no veterans who've been through it, no "just do what you did last year" reassurances from colleagues.
That might feel unsettling. It shouldn't. Here's exactly what to expect.
First, a quick recap of what MTD actually changes
Under the old system, you filed one Self Assessment return per year — usually months after the tax year had ended. Under Making Tax Digital for Income Tax, you'll now submit a summary of your income and expenses to HMRC four times a year, with a final end-of-year declaration to wrap things up.
The quarterly submissions are not your tax return. They don't calculate your final tax bill. Think of them as progress updates — you're telling HMRC what came in and what went out during that quarter. The final reckoning still happens at the end of the year.
The first quarterly period
The tax year runs from 6 April to 5 April. That means the first quarterly period under MTD covers 6 April to 5 July 2026. You then have one month to submit — giving you a deadline of 7 August 2026.
So in practical terms: you're capturing roughly three months of income and expenses, then submitting a summary of that to HMRC. That's it.
What you actually need to submit
Your quarterly update to HMRC will include:
- Your total income from self-employment during the quarter — for most locum doctors, this means your locum payments
- Your total allowable expenses broken down by category — things like GMC fees, indemnity cover, mileage, professional development, and any equipment or software used for work
You're not submitting receipts. You're not uploading bank statements. You're submitting totals, organised by category. HMRC receives a structured summary, not a pile of documents.
This is important to understand because a lot of people assume the quarterly submission is some kind of deep audit. It isn't. It's a summary.
The soft landing in year one
HMRC has confirmed a soft landing period for the first year of MTD. This means that if your quarterly submissions aren't perfect — if you miss some expenses, misclassify something, or submit slightly late — you're unlikely to face penalties. HMRC understands this is new for everyone.
That said, the soft landing is not an excuse to ignore the deadline entirely. It's a safety net for genuine errors and minor issues during the adjustment period, not a free pass to skip submissions.
What you need to have in place before April
To make your first submission as smooth as possible, there are a few things worth sorting before April arrives:
Compatible software. HMRC requires you to submit through MTD-compatible software — you can't do it through your personal tax account or by calling HMRC directly. Make sure your software is HMRC-recognised before 6 April.
A record of your income. Keep a running log of your locum payments as they come in. Your payslips or payment confirmations from the agencies or trusts you work with are your primary source.
A habit of logging expenses. You don't need to do this daily, but doing it monthly is much easier than reconstructing three months of spending in July. Set a reminder for the first weekend of each month.
Your UTR and National Insurance number. You'll need these on file in your software. If you haven't done Self Assessment before, you'll need to register with HMRC first — don't leave this until July.
What happens after you submit
Once your quarterly update is submitted, HMRC's systems will provide an estimate of your tax liability to date. This is just an indicator based on the information submitted so far — it doesn't mean you owe that amount now.
At the end of the tax year (after 5 April 2027 for the first MTD year), you'll complete a final declaration. This is where you confirm your income and expenses for the full year, add any additional information like Gift Aid donations or pension contributions, and confirm your final tax position. Payment deadlines remain the same as under Self Assessment.
It's less daunting than it sounds
The quarterly submission has been described in some corners of the internet as a massive compliance burden. In reality, for a locum doctor with straightforward self-employment income, it comes down to:
- Log your income as it arrives
- Log your expenses as you incur them
- Once a quarter, submit a summary through your software
If you've been doing Self Assessment — where you try to remember an entire year of finances in one go — quarterly submissions are actually easier. The information is fresh. The amounts are smaller. The pressure of one annual deadline is spread across four smaller ones.
The first submission will feel unfamiliar. The second will feel routine.
Duly Filed is built specifically for self-employed healthcare professionals navigating MTD for the first time. We handle the HMRC connection, the submission formatting, and the quarterly deadlines — so you can focus on your patients. Find out more.