If your gross income from self-employment or property took you over £50,000 on your 2024/25 tax return, you are now inside Making Tax Digital for Income Tax — and the clock is running on your very first obligation. The first quarterly period (6 April to 5 July 2026) has already closed. The update covering it is due by 7 August 2026. That gives you roughly five weeks from today to get it right. This is a practical, week-by-week checklist rather than another explainer of the rules — read our full rules breakdown here if you still need the basics.
Where You Should Already Be
- Digital records running since 6 April — bank feeds connected in MTD-compatible software, or a spreadsheet linked through bridging software
- Every income and expense line for the quarter allocated to the correct business (self-employment and property are reported separately, even if it's the same person)
- An HMRC online account set up and, if using an agent, authorisation in place so your accountant can file on your behalf
If any of that isn't true yet, don't panic — five weeks is enough to catch up, but only if you start now rather than in week four.
The Five-Week Plan
| Week | What to do |
|---|---|
| Now | Reconcile every bank transaction from 6 April to 5 July. Chase any missing invoices or receipts while they're still easy to find. |
| Week 2 | Categorise everything correctly — mixing personal and business spending, or misclassifying capital purchases as expenses, is the most common error at this stage. |
| Week 3 | Run a draft summary in your software and sense-check it against what you'd expect for the quarter. If a figure looks wrong, this is the week to find out why. |
| Week 4 | Send the draft to your accountant (or do a final self-review) well before the deadline — not the night before. |
| By 7 August | Submit. Keep the confirmation receipt from HMRC's system as proof of submission. |
Mistakes That Catch People Out
- Treating it like a mini tax return. A quarterly update is a running total of income and expenses — you're not calculating tax due each quarter, so don't lose a weekend trying to.
- One submission for two income streams. If you're both self-employed and a landlord, you file a separate update for each business.
- Assuming a bridging spreadsheet "just works". Test the link between your spreadsheet and the bridging software before the deadline week, not during it.
- Forgetting cumulative figures reset per quarter, not per year — check your software is reporting the right period, especially if you set up mid-quarter.
What Happens If You Miss It
One missed deadline means one penalty point — it isn't an automatic fine. But points build towards a real financial penalty, and the rules are stricter than most people expect. Our full breakdown of the points system covers exactly how many points trigger a penalty and how to get them removed.
How SMD Accountancy Can Help
We're filing first-quarter MTD updates for clients right now. If you want someone else checking your figures before 7 August, get in touch this week — the closer we get to the deadline, the less time there is to fix problems before they become a missed submission.