Making Tax Digital for Income Tax: Are You Caught?

The trap most people miss: MTD adds your income streams together

The headline is simple - Making Tax Digital for Income TaxMaking Tax Digital for Income Tax: HMRC's shift to digital tax: since April 2026, sole traders and landlords above the qualifying-income threshold must keep digital records and send quarterly updates instead of one annual Self Assessment return. (MTD for IT) becomes mandatory from 6 April 2026 for sole traders and landlords earning over £50,000. The catch is in the two words HMRC uses and most summaries skim over: qualifying income.

Qualifying income is your gross income - turnover, before a penny of expenses - from self-employment and property added together. That combination is what catches people out. HMRC's own worked example: £25,000 of rental income plus £27,000 of self-employment is £52,000 of qualifying income - over the line - even though neither source alone reaches £50,000, and your actual profit after costs might be half that.

So the first question is not "is my business over £50,000?" It is "is my combined gross self-employment and property turnover over the threshold?" The Self-Employed Tax Calculator shows what that turnover actually leaves you after Income Tax and National Insurance - a very different figure from the gross number MTD is testing you against.

Who is caught, and when

MTD for Income Tax arrives in three waves, each lowering the qualifying-income threshold. HMRC looks at the Self Assessment return you filed for the tax year shown, then writes to confirm you are in - but you are responsible for checking yourself, letter or no letter.

Being caught does not sign you up

This is the step most summaries leave out, and it is the one that bites first. Crossing the threshold makes MTD apply to you. It does not enrol you. You, or your accountant, have to sign up through HMRC's online service as a separate, deliberate act - and until that is done your software cannot send anything at all.

HMRC does write to people it believes are caught, but that letter is a notification, not a registration. It is also not what creates the obligation: you are caught by your figures, whether or not a letter arrives.

Two prerequisites catch people out at the sign-up screen: you must already be registered for Self AssessmentHMRC's system for reporting income and gains not taxed at source. The online return and payment deadline is 31 January after the tax year ends., and you must have filed a return within the last two years. If you have only recently started trading and have never filed, you cannot sign up yet.

If you use an accountant, their existing authorisation to file your Self Assessment does not automatically let them act for you under MTD. It has to be moved across into their agent services account, or you authorise them for MTD directly. Worth one email to confirm they have done it rather than each of you assuming the other has.

What counts as qualifying income - and what does not

Qualifying income is the combined gross income from all your self-employment and property (UK property, plus foreign property if you are UK resident). It is measured before expenses. What does not count toward the threshold:

• Employment (PAYE) salary
• Your share of profit from a partnership - it stays off the threshold and outside the quarterly updates, but you still report it on your final return through your software
• Dividends - including those from your own company
• State Pension and private pensions

Two traps live inside the definition. Jointly-owned property: only your share counts - a £50,000 jointly-let property split equally is £25,000 each. Ceased sources: if one trade or let has stopped but another self-employment or property source continues, the income from the ceased source still counts toward the threshold for that year. And stopping altogether does not release you by itself - if all your self-employment and property income has ceased you have to tell HMRC before the start of the next tax year, and you are only out once HMRC confirms it in writing. Assume you have dropped out silently and you are still mandated.

What "quarterly" actually means

People picture four mini tax returns. It is not that. Each quarterly update is a cumulative running total of your income and expenses so far in the year - Q2 includes Q1, Q3 includes Q1 and Q2, and so on. They are light-touch summaries sent straight from compatible software, not returns you sit down and "complete".

One update per income source, not one per person. Each self-employment and each property business reports separately, on its own cycle. So the reader in the example above - £27,000 of self-employment plus £25,000 of rent - sends two updates every quarter, not one, and keeps the two sets of records apart. Two trades plus a let would be three. This is the detail that turns MTD from an annoyance into a workflow.

Under £90,000 of turnover, the update gets much lighter. Below that figure you can categorise in less detail - broadly a total for income and a total for expenses, rather than a full breakdown. Two things to get right about it. First, the test is applied per income source, not to your combined qualifying income: if you have a trade and a let, each one has to be under £90,000 in its own right, so a trader on £70,000 plus a let on £70,000 still qualifies on both despite a combined £140,000. Second, residential landlords do not get the full simplification: if you receive UK property income from residential property you must still identify separately whether an expense is a restricted finance cost - mortgage and other finance interest - even when you are under the threshold. The figure is pegged to the VAT registration threshold, so it moves if that moves.

Figures can also be provisional. An update is a summary, not a certified account: if something is not yet reconciled you send your best estimate and correct it later, either in the next cumulative update or in the tax return at the end. Nothing you put in a quarterly update is locked in.

After the four updates you submit your tax return - the step that replaces your old SA100. HMRC's own guidance now simply calls it submitting your tax return, though you will still hear it called the final declaration, which is what much of the profession and some software call the same thing. It is where you confirm the year's figures, add anything outside MTD (employment, dividends, a partnership share), claim your reliefs, and the tax is calculated. Its deadline is the familiar one: 31 January after the tax year ends - so for the first mandated year, 2026/27, that is 31 January 2028.

The deadlines - and a worked first year

Each standard quarter ends on the 5th, and the update is due about a month later, on the 7th. The column below shows the quarter that closes; remember from the section above that what you actually send each time runs cumulatively from 6 April, so the Q3 update covers 6 April to 5 January, not just October to January:

Some software lets you use calendar-month quarters instead (ending 30 June, 30 September, 31 December and 31 March). The deadlines do not move if you do - only the periods they cover. It is a setting in your software rather than an election to HMRC, but you have to choose it for each income source before you send your first update of the year, because you cannot switch part-way through.

So the trader-plus-landlord in our example - two income sources, so two updates each time - faces this exact 2026/27 calendar:

• 7 Aug 2026 - Q1 updates (6 Apr to 5 Jul): one for the trade, one for the property
• 7 Nov 2026 - Q2 updates
• 31 Jan 2027 - nothing to do with MTD, but this is when the 2025/26 balancing paymentThe top-up you pay on 31 January once your actual tax bill is known: your full Self Assessment liability for the year, minus any payments on account you already made toward it. Capital Gains Tax and student loan repayments always land here. and the first payment on accountAdvance instalments toward your next Self Assessment bill, due if the bill tops £1,000. Two payments (31 January and 31 July), each 50% of the prior year's tax - so the first January can be about 150% of the tax. for 2026/27 fall due
• 7 Feb 2027 - Q3 updates
• 7 May 2027 - Q4 updates
• 31 Jul 2027 - second payment on account for 2026/27
• 31 Jan 2028 - the tax return for 2026/27, plus that year's balancing payment and the first payment on account for 2027/28

Note what MTD does not change: when you pay. If payments on account already apply to you they carry on exactly as before, two instalments plus a balance, on the same dates. The number due on 31 January 2028 is the balance for the year, not the whole year's tax - which is why a calendar that shows only the quarterly updates and a single January payment misleads on both counts.

The soft-landing trap

There is a genuine concession for the first year: HMRC will not charge a penalty for missing a quarterly update deadline in 2026/27. You must still keep digital records and send the updates - but a late one will not cost you in that first year.

From 2027/28 the quarterly updates join that system too. It is points-based: one point per missed deadline, and at 4 points a £200 penalty - then a further £200 for every later miss. Below four points, each one clears automatically 24 months after the missed deadline; once you reach four, you only clear them by filing on time for 12 months and sending any outstanding submissions from the previous 24. Note that it is one shared tally: quarterly updates and your tax return both feed the same four-point threshold, rather than running separate counts. The threshold only drops - to 2 points - if you later become exempt from MTD, and if that happens any points you already hold are rebased so you are no closer to the new threshold than you were to the old one.

Late payment is a separate regime, and a harsher one than it replaced. Everything above is about late submissions. Paying late is charged differently and is not points-based. From the tax year you join MTD: nothing for the first 15 days; then 3% of the tax still outstanding at day 15 for 2026/27, rising to 4% from 2027/28; a further 3% (or 4%) on whatever is still outstanding at day 30; then charging at 10% a year, accruing daily, from day 31. In your first year under the new penalties you get 30 days from the due date to pay or contact HMRC before anything is charged, and after that first year the window drops to 15 days. You only get that 30-day run once, so if you volunteered for MTD before being mandated you have already used it.

The one relief: these late-payment penalties do not apply to payments on account.

Once you are in, you are (mostly) in

Mandation is sticky. A single quieter year does not release you: once you are using MTD for Income Tax, you can only stop if your qualifying income stays below the relevant threshold for three tax years in a row (or you qualify for an exemption). Plan as though it is permanent, because for most people it will be.

What you need to do - and what it really costs

Four practical steps, in this order:

1. Sign up. The step covered above, and the one nobody warns you about. Nothing else can happen until it is done.

2. Keep digital records. Your income and expenses must sit in MTD-compatible software that can talk to HMRC's systems directly. A spreadsheet cannot submit on its own - but it can stay as your underlying record if it is digitally linked to bridging software that files on its behalf, which is a route HMRC explicitly allows. "Digitally linked" means linked cells or an import; retyping figures across breaks the link.

3. Send a quarterly update for each income source, four times a year each.

4. Submit your tax return by the 31 January after the tax year ends.

The cost, honestly: HMRC does not supply software of its own and has said it will not - you pick a product from the GOV.UK software finder. But that is not the same as MTD necessarily costing you money. HMRC's own guidance says free products are available for people with simple tax affairs, its finder flags which listed products have a free version, and several banks bundle a compatible package with a business account. The catch with the free tiers is limits rather than quality: caps on transactions or invoices per month, one bank connection, a single user, sometimes a tie to one particular bank. Paid entry-level products start well below the price of a full accounting package.

So the honest advice is neither "budget for a new subscription" nor "it is all free". Check the finder against your own position - how many income sources, what transaction volume, whether you are VAT registered, which bank you use - before you assume you have to spend anything, and equally before you assume a free tier will stretch to cover you.

Exemptions - and the categories that are simply out

Two different things get called an exemption here, and only one of them needs an application.

You apply if you are digitally excluded - for example by age, disability or health, a location without reliable internet, or religious grounds incompatible with using electronic systems. It is not automatic and not assumed: you apply to HMRC, and if it is granted you carry on through Self Assessment as before.

You are outside it anyway, without applying, if you fall into an excluded category. The main ones: you have no National Insurance number before the tax year starts; the income is reported on a trust return, or you are a personal representative dealing with a deceased person's affairs; you are a Lloyd's member, for your underwriting business; or you are not physically or mentally capable of reporting to HMRC and a power of attorney, deputy or guardian is in place. One caution on the trust route: it exempts the trust's income, not you - if you also have your own self-employment or property income, that can still be caught on its own merits. Ministers of religion, and people claiming Married Couple's Allowance (born before 6 April 1935) or Blind Person's Allowance, are also outside it. Others are deferred rather than excluded - averaging relief, qualifying care relief, trust and estate income, and a range of non-residence cases are held back until at least April 2027. Partnerships sit outside MTD for Income Tax altogether for now, with no start date announced.

If you think one of these covers you, check it before you sign up rather than after, and check it against GOV.UK's exemption guidance directly - that list was revised more than once during 2026.

Related: if you also have a PAYE job, see employed and self-employed; estimate what your profit actually leaves you with using the Self-Employed Tax Calculator; and the Self Assessment bill guide covers the tax return and the 31 January deadline; and since MTD obligations differ by structure, sole trader vs limited company covers that decision.