When does Making Tax Digital start for builders?

It depends on your turnover before expenses. Builders over £50,000 started on 6 April 2026, over £30,000 start on 6 April 2027, and over £20,000 start on 6 April 2028. Limited companies are not included.

Making Tax Digital for Income Tax (MTD) means keeping digital records, sending HMRC an update every quarter and filing your tax return through software. It covers self-employed builders, plumbers, electricians, joiners and every other trade working as a sole trader. HMRC estimated on 5 October 2026 that around 1,077,000 more sole traders and landlords will join from 6 April 2027.

The three start dates

The 2025-26 tax return is due by 31 January 2027, so if you are near £30,000 you may only know for sure when you file it.

How CIS pay counts

Qualifying income is your self-employment and property income before expenses. HMRC also calls it turnover. It is not your profit, and it is not the money that reaches your bank after CIS deductions. GOV.UK tells subcontractors to record their total pay before deductions as income, so that gross figure is the one that counts.

A worked example. A bricklayer on CIS had £26,000 paid into the bank in 2025-26, after contractors deducted 20%. The pay before deductions was £32,500. That is over £30,000, so MTD starts for them on 6 April 2027, even though the bank shows less.

Wages from a job, dividends and pensions are not counted. Rental income is, so a builder with a buy-to-let adds both together.

What this means for you

If you are a sole trader over the line, from 6 April 2027 you will need to:

• keep digital records of every sale and cost. If your turnover is under £90,000, each item only needs to be marked as income or expense
• send a quarterly update through software after each quarter. Each update is a running total for the tax year so far
• file your tax return through MTD software by 31 January after the year ends

Your tax is still paid on the same dates. Quarterly updates are reports, not payments. HMRC adds your CIS deductions to your MTD tax return, and you must check them before you submit. Any CIS refund is still claimed only after the year ends, never during it.

The penalties are tighter. Each missed deadline earns one penalty point, and at 4 points there is a £200 penalty. GOV.UK says there are no points for missed quarterly updates in 2026-27, and at the Budget on 28 October 2026 the government said builders who must start in April 2027 will get no points for late 2027-28 updates either. The updates must still be sent, and from 2028-29 a missed one earns a point. Late payment penalties for 2027-28 are 4% of tax unpaid at day 15, another 4% at day 30, then 10% a year from day 31.

Steps to take before 6 April 2027

1. Add up your 2025-26 turnover before expenses: CIS pay before deductions, other work, and any rent.
2. Use the free MTD check to confirm which start date applies to you.
3. Check you are registered for Self Assessment and have filed a return in the last 2 years. You need both to sign up.
4. File your 2025-26 tax return early, so you know your figure and any CIS refund is not left waiting.
5. Choose MTD software, or someone to do the updates for you, and start keeping digital records now.
6. Sign up for MTD and put the quarterly deadlines in your diary.

Dates for your diary

You can choose calendar quarters instead, ending 30 June, 30 September, 31 December and 31 March. The due dates stay the same. The trades section has more guides on CIS, VAT and software for the building trades.