Who can do my Making Tax Digital quarterly updates for me as a builder?

You, or an agent you authorise through HMRC: an accountant, a bookkeeper or a managed service. A once-a-year CIS refund firm may not cover the updates. For 2027 joiners, the first is due 7 August 2027.

Making Tax Digital for Income Tax (MTD) asks for four quarterly updates a year, sent from compatible software, then a tax return. For a builder on the Construction Industry Scheme (CIS), in our reading the updates take your gross pay, not what reached the bank. This page follows GOV.UK as checked on 18 October 2026.

Your options as a builder

Why your refund firm may not be enough

Many builders use a firm once a year to claim back over-deducted CIS through their tax return. Under MTD that changes in two ways. First, there are four quarterly updates as well as the return, and a once-a-year service may not include them. Second, GOV.UK says you cannot claim a refund in the MTD tax return itself. HMRC adds the CIS deductions it holds to the return, you check them, and any refund is then requested through your HMRC online services account, or by your main agent through its agent services account.

Ask any firm you use now whether it will send your updates from your MTD start date, which is already April 2026 if you were over £50,000 in 2024-25, whether it will be your main agent with HMRC, and how its fee works. In our experience, fees are often fixed or a share of the refund.

What a builder's agent needs from you

• Monthly CIS statements from each contractor. They show the gross paid, any materials and the deduction. In our reading, your income is the gross, not the amount after the deduction.
• Payments from homeowners, who are outside CIS.
• Receipts for materials, tools, van and fuel, or a bank feed the agent can read.
• Your 2024-25 and 2025-26 figures, to confirm your start date.

In our reading, the deduction itself is tax already paid, not a cost. If your turnover is under £90,000, each item only needs to be marked as income or expense.

What any agent must have

• An HMRC agent services account. An agent needs one to sign clients up for MTD. HMRC now requires most people paid to deal with it about someone else's tax to register, through this account. Registration opened on 18 May 2026.
• Money-laundering supervision, by HMRC or a professional body.
• Your authorisation, not your password.

You can have one main agent and any number of supporting agents. A main agent can send updates and your tax return. A supporting agent can send updates but not the tax return, and cannot see your tax calculation.

What this means for you

MTD started on 6 April 2026 if your qualifying income was over £50,000 in 2024-25. Otherwise it starts on 6 April 2027 if your 2025-26 qualifying income was over £30,000, or on 6 April 2028 if it was over £20,000 in 2026-27. Qualifying income is self-employed and property income before expenses, and in our reading, for CIS work that means before deductions.

If you start in April 2027, your first update covers 6 April to 5 July 2027 (or 1 April to 30 June) and is due by 7 August 2027. If you have been in MTD since April 2026, your updates are already running, and the next is due by 7 November 2026. GOV.UK says there are no penalty points for late updates in 2026-27. At the Budget on 28 October 2026 the government said people who must join in April 2027 will get no penalty points for late 2027-28 updates either, though updates must still be sent. For them, the earliest a late update can earn a point is 7 August 2028. If you have been in MTD since April 2026, a late 2027-28 update can earn a point. Four points means a £200 penalty.

If you would rather hand it over, our Trades Tax plan is £35 a month including VAT. The founding offer for the first 500 trades clients is £5 a month for your first 3 months, then £35 a month. Cancel any time. We'll remind you before it changes. Our tax plans start once our HMRC registrations are complete. Until then you can join the waitlist, and no payment is taken.

Steps to hand over your updates

1. Use the free MTD check to confirm your start date. In our reading, CIS pay counts before deductions.
2. Ask your current accountant or refund firm whether it will send quarterly updates, and at what price.
3. Ask whether it has an HMRC agent services account and money-laundering supervision.
4. Agree whether it will be your main agent, which includes the tax return.
5. Get the fee in writing, including VAT, and how any CIS refund reaches you.
6. Accept the authorisation request through HMRC, and send each month's CIS statements as they arrive.

There are more guides in the trades section.