The Short Answer
MTD stands for Making Tax Digital. It's HMRC's move away from one big tax return a year, towards keeping digital records and sending them updates every three months instead.
Dan earns £62,000 a year from his building work. From April 2026, instead of one Self Assessment return, he now sends HMRC a quick digital update every quarter using software, then a final wrap-up at the end of the year.
It's not a new tax. You're not paying HMRC more. It's the same figures, just reported more often and digitally instead of on paper or by post.
Does It Apply to You (and When)?
MTD is rolling out in stages, based on how much you earn from self-employment and/or renting out property, added together:
- Over £50,000 — you're in it already, from April 2026
- Over £30,000 — you'll join from April 2027
- Over £20,000 — you'll join from April 2028
HMRC looks at what you earned two tax years before your start date to work out when you're brought in. So if you're already over £50,000, this isn't something to think about "one day"... it's already begun.
Which Year's Income Actually Gets Checked
This is the part that catches people out. HMRC doesn't look at what you're earning right now, it looks at a tax return you've already submitted, from two years before your start date.
| Your MTD start date | Income year HMRC checks | Threshold |
|---|---|---|
| 6 April 2026 | 2024/25 (return filed by 31 Jan 2026) | Over £50,000 |
| 6 April 2027 | 2025/26 (return filed by 31 Jan 2027) | Over £30,000 |
| 6 April 2028 | 2026/27 (return filed by 31 Jan 2028) | Over £20,000 |
Because it's based on a return you've already filed, you can actually work out your own start date in advance rather than waiting for HMRC to tell you.
Dan's 2024/25 income was £55,000, so he's in MTD from April 2026. The following year his income drops to £40,000, but he stays in MTD anyway. Once you're in, you're in, even if your income later falls below the threshold that brought you in.
What If This Is Your First Self Assessment Return?
You get a bit of breathing room here. You can't be brought into MTD until after you've submitted your first ever Self Assessment tax return, because HMRC has no previous return to check your income against yet.
Sam starts self-employment partway through 2025/26 and earns £58,000 that year. His first tax return, covering 2025/26, is due by 31 January 2027. Because it's his first return, he isn't mandated the moment he files it. MTD only kicks in from the next applicable start date once HMRC has a return on file to check.
In other words: your very first year of trading is always safe from MTD, however much you earn. It's only once you've got a filed return on record that the clock starts.
What You'll Actually Have to Do
There are three parts to it, and none of them are as scary as they sound:
- Keep your income and expenses recorded digitally, rather than on paper or in a shoebox
- Send a short update to HMRC every three months, summarising what came in and went out
- Submit a final declaration at the end of the tax year, confirming everything and adding any allowances or adjustments
The quarterly updates are quick summaries, not full tax calculations. Think of them as a running total, not a mini tax return.
What It Doesn't Change
It's easy to assume MTD means more tax, more rules, or more chances to get things wrong. It doesn't. It's the same income, the same expenses, and the same tax bill at the end of the year, just reported through software instead of once a year on paper.
Do I Need to Do Anything Right Now?
If you're already over the £50,000 threshold, yes! There are two separate steps: signing up for MTD with HMRC itself, and getting MTD-compatible software set up to send your quarterly updates. Doing one without the other won't cut it. If you're below the threshold, there's nothing urgent, but it's worth keeping digital records now so the switch isn't a scramble later.
Either way, this is exactly the kind of thing worth checking with your accountant rather than guessing. A five-minute conversation now saves a lot of stress later.
The Shoebox's Retirement Party
After years of loyal service, crumpled receipts, a mystery petrol stub from 2019, and at least one napkin with numbers scribbled on it, the shoebox can finally retire. It had a good run. It just won't be doing your tax return anymore.