MTD for sole traders: the 2026 guide to Making Tax Digital for Income Tax

Who qualifies — and why the test is on gross turnover

The MTD test for sole traders is on gross self-employment turnover, before expenses. That is the figure on the SA103 self-employment pages of your Self Assessment return — not your taxable profit, not your net of capital allowances, not your bank-statement deposits.

Two worked examples make the line obvious:

• Freelance designer. Turnover £55,000. Allowable expenses (software, travel, use-of-home, training): £15,000. Net profit: £40,000. In scope from April 2026 — the £55,000 turnover, not the £40,000 profit, is what counts.
• Sole-trade plumber with a side flat. Self-employment turnover £35,000. Gross rental income from one buy-to-let: £20,000. Combined qualifying income: £55,000. In scope from April 2026, even though neither stream alone would qualify (LITRG).

If your turnover is at or under £50,000 for 2024/25 you are not in the April 2026 phase, but you should re-check against the £30,000 and £20,000 phases as your income changes.

Read the full who-is-in-scope guide →

The combined-income trap

The most common surprise: small income streams that, looked at separately, never felt like “big” numbers — but added together cross the line.

The rule from HMRC: gross self-employment turnover plus gross rental income are added against one threshold. A freelancer with £35,000 of design work who also lets one ex-home for £20,000 of gross rent has £55,000 of qualifying income. From 6 April 2026 they are in MTD — and they will need two sets of quarterly updates, one for the sole trade and one for the property business (GOV.UK).

This catches three kinds of people most often: tradespeople who own a single let, consultants who inherited a property, and creative freelancers with an Airbnb or holiday-let sideline.

What sole traders actually have to do

Three obligations replace the annual Self Assessment return:

• Digital records. Business income and allowable expenses tracked in compatible software throughout the year — not paper, not standalone spreadsheets unless they are bridged to compatible software. Records kept as you go.
• Cumulative quarterly updates. Four updates a year, each one showing the year-to-date position rather than just the latest quarter. The standard deadlines for an April-aligned period are: Q1 — 7 August, Q2 — 7 November, Q3 — 7 February, Q4 — 7 May. Correcting an earlier mistake is a matter of re-stating the cumulative figure in the next update.
• Final declaration. After the tax year ends you confirm the figures, add any other income (employment, savings, dividends, partnership share), and finalise your tax — replacing the annual return. The deadline is 31 January after the tax year ends, so the first MTD final declaration for 2026/27 is due by 31 January 2028.

Payment dates for your tax bill do not change: 31 January (balancing payment plus first payment on account) and 31 July (second payment on account). Only the reporting cadence becomes quarterly.

Read the full quarterly-cycle breakdown →

Allowable expenses — same rules, more often

MTD does not change which expenses are allowable; it changes how often they are reported. The wholly-and-exclusively test still applies, the same capital-vs-revenue boundary still applies, and the simplified-expense rules continue to be available.

The areas that catch sole traders out most often under quarterly reporting:

• Simplified expenses. Flat-rate mileage, working-from-home, and live-at-business-premises allowances are unchanged (GOV.UK simplified expenses). You can still elect for simplified mileage on a per-vehicle basis, and the £10/£18/£26 monthly working-from-home rates still apply by hours-worked-at-home thresholds. The change is timing: you apply them when posting expenses in your software, not in a January reconciliation.
• Use-of-home calculations. If you claim a proportion of household bills instead of the flat rate, the apportionment workings (room count, hours used) need to live alongside the digital records — quarterly updates will surface gaps in your method earlier than the annual cycle did.
• Mixed-use assets. A vehicle, phone, or laptop with both business and private use still needs a defensible business-use percentage. Under MTD, that percentage is applied as you go, not retrofitted at year-end.

Can sole traders still use cash basis under MTD?

Yes. Cash-basis accounting remains available for sole traders under MTD for Income Tax — and since 6 April 2024 it is the default basis for most unincorporated businesses, with traditional accruals as an opt-in election.

The cumulative-update mechanism works for both bases. On cash basis you record income when money is received and expenses when paid; on accruals basis you record income when earned and expenses when incurred. Pick the basis you would have used under Self Assessment — MTD does not push you onto a different one.

What about partnerships?

Two situations that arise in practice:

• Sole trader who joins a partnership mid-year. The sole-trade side stays inside MTD (until you formally cease that trade); the partnership share is reported through the partnership return for now.
• Partner with a separate side trade. The side trade is treated as a sole trade for MTD purposes; the partnership share sits outside the regime. Only the side-trade turnover (plus any rental income) counts toward your qualifying-income test.

How sole traders should prepare

A practical, do-it-now sequence:

1. Check your phase. Look at your 2024/25 SA103 turnover plus any SA105 gross rent. Over £50,000? You are in from April 2026. Under £50,000 but over £30,000? Plan for April 2027.
2. Pick a basis. Confirm whether you stay on cash basis (the default) or elect for accruals.
3. Choose software. All-in-one bookkeeping (Xero, FreeAgent, QuickBooks) or bridging software linked to a spreadsheet. Decide before April so you have a clean opening balance.
4. Go digital early. Start recording income and expenses in software now — the habit is the hard part, not the tech.
5. Sign up and authorise. Register for MTD-IT and authorise your software or agent before your first quarterly update is due.
6. Do a dry run. Simulate a quarterly update before it counts.

Read the full preparation checklist →

If you miss a quarterly update

MTD uses a points-based late-submission system: one penalty point per missed deadline, with a £200 charge at four points and a further £200 for each later miss. There is a soft landing for 2026/27 — no penalty points for late quarterly updates in the first year for April 2026 joiners. The soft landing does not cover the final declaration deadline or late-payment penalties.

Read the full penalty + soft-landing guide →

Useful free tool while you're here

Self Assessment tax calculator — model your sole-trader tax bill for 2026/27 before the year ends, so the final declaration in January 2028 is a confirmation, not a surprise.