MTD for Income Tax — What Sole Traders Need to Do Before April 2026

What MTD for Income Tax is

Making Tax Digital for Income Tax Self Assessment (MTD ITSA) replaces the annual Self Assessment tax return for most sole traders and landlords with quarterly digital submissions. Instead of one annual return, you will submit:

• 4 quarterly updates each tax year (summarising income and expenses)
• A final declaration (replacing the current tax return) by 31 January following the tax year end

Who is affected and when

Income here means gross business income — not profit. If your total turnover from all your businesses and rental properties combined exceeds the threshold, MTD ITSA applies.

What changes in practice

Currently, you file one Self Assessment return per year. Under MTD ITSA, you keep digital records throughout the year and submit quarterly summaries directly to HMRC through your accounting software.

The quarterly updates do not need to be perfect — they are an ongoing summary, not a final tax calculation. You have until the end-of-period statement and final declaration to make corrections and claim reliefs.

The final declaration deadline remains 31 January — this does not change. What changes is how information gets to HMRC.

The software requirement

From your MTD ITSA start date, you must use HMRC-recognised software to keep your business records and submit quarterly updates. You cannot use spreadsheets alone — they must be linked to MTD-compliant software.

Compatible software includes Xero, QuickBooks, FreeAgent, and several others. Most major cloud accounting platforms have already built MTD ITSA into their software.

What to do now if you are above £50,000

Step 1: If you are not already using cloud accounting software, sign up for Xero, QuickBooks, or FreeAgent and connect your bank feed.

Step 2: Sign up for MTD ITSA pilot through your software provider or via your bookkeeper. HMRC has been running voluntary pilots since 2021.

Step 3: Ensure your records are clean and reconciled from the start of the 2026/27 tax year (6 April 2026).

Step 4: Know your quarterly submission deadlines:

• Q1 (6 Apr – 5 Jul): submit by 5 August
• Q2 (6 Jul – 5 Oct): submit by 5 November
• Q3 (6 Oct – 5 Jan): submit by 5 February
• Q4 (6 Jan – 5 Apr): submit by 5 May
• Final declaration: by 31 January 2027

What happens if you miss a quarterly submission

MTD ITSA uses a points-based penalty system. Each missed submission earns one penalty point. When your points total reaches a threshold (4 for quarterly filers), a £200 financial penalty applies. Points reset after a clean period of compliance.

This is different from the current Self Assessment penalty system — and significantly stricter for people who miss submissions repeatedly.

The real impact of MTD ITSA

MTD ITSA forces better bookkeeping. Sole traders who previously left their accounts until January now need their records maintained throughout the year. For those already using cloud accounting software and reconciling monthly, the practical impact is minimal. For those on spreadsheets or who reconcile annually, it is significant.

The cost of getting this right before April 2026 is far lower than the cost of scrambling to comply after the mandate applies.