When does HMRC start automatically signing people up for Making Tax Digital?

HMRC begins auto-enrolling qualifying sole traders and landlords into MTD for Income Tax from September 2026, working through the affected population in stages over several months. Those in scope had combined self-employment and property income above £50,000 in the 2024/25 tax year and were required to join from 6 April 2026.

What should I do if I receive an HMRC MTD auto-enrolment letter?

Do not ignore it. You must begin keeping digital records and filing quarterly updates using MTD-compatible software from the effective date on the letter. HMRC has waived penalty points for late quarterly updates during 2026/27, but late self assessment payment penalties and interest charges still apply as normal.

Can I still use spreadsheets for Making Tax Digital for Income Tax?

You cannot use spreadsheets alone. HMRC requires records to be held in MTD-compatible software or in spreadsheets linked to HMRC through approved bridging software. Manually retyping figures between systems breaks the required digital link and creates a compliance risk at the year-end final declaration.

How does automation help with MTD quarterly filing?

Automated workflows can pull invoices from your accounting software, categorise transactions from your bank feed, flag missing receipts and prepare each quarterly update for review. A human then approves it before submission, which cuts filing time and reduces the errors that would trigger amendments and rework at the final declaration.

HMRC Making Tax Digital Auto-Enrolment: What UK Sole Traders and Landlords Must Do Before September 2026

From September 2026, HMRC will start automatically signing up sole traders and landlords who should already be on Making Tax Digital for Income Tax but have not registered. If your combined self-employment and property income exceeded £50,000 in 2024/25, you are in scope. You need MTD-compatible software and a quarterly filing process in place now, not after the letter arrives.

Who does the September 2026 auto-enrolment affect?

The programme targets people who were required to join MTD for Income Tax from 6 April 2026 and have not signed up voluntarily. The qualifying threshold is combined gross income from self-employment and property above £50,000 in the 2024/25 tax year. From April 2027 the threshold drops to £30,000, pulling in a much larger group.

HMRC will enrol taxpayers in stages over several months. New guidance is expected in late August 2026 for those receiving a registration letter, and the effective date in the letter is when quarterly obligations begin.

Why has HMRC decided to auto-enrol?

HMRC confirmed that 436,000 sole traders and landlords filed their first digital quarterly update ahead of the 7 August 2026 deadline, according to reporting by Taxi Point and TaxAssist Accountants. Roughly one third of those required to sign up from April 2026 still had not done so, which is what prompted the auto-enrolment programme.

The adoption gap in real numbers

The Register reported earlier this year that fewer than three in ten of those affected had signed up during the voluntary window. That gap is now being closed by HMRC on the taxpayer's behalf, and the compliance clock starts from the letter's effective date, not from when it is opened.

What quarterly filing under MTD actually requires

You must keep digital records of income and expenses in MTD-compatible software. Spreadsheets are only permitted if they connect to HMRC through approved bridging software that preserves a digital link end to end. Quarterly updates submit summary income and expense totals to HMRC, followed by a final declaration after the tax year.

Penalty points for late quarterly updates are waived during 2026/27. Late self assessment penalties still apply, and errors carried through to the final declaration can still create rework and interest charges.

How to prepare before HMRC's letter arrives

Confirm whether your 2024/25 combined self-employment and property income exceeded £50,000.
Choose MTD-compatible software from HMRC's approved list and register early.
Digitally link your bank feed, invoicing tool and expense records so nothing is retyped.
Assign responsibility for quarterly updates to a named person, with a diary reminder for each deadline.
Automate the repeatable parts: bank transaction categorisation, receipt capture, missing-invoice chasing and the pre-filing check.

The role of AI agents in quarterly filing

An AI agent sits on top of your existing accounting stack. It pulls invoices as they clear, matches them to the correct tax categories, flags anything unusual for review and drafts each quarterly update for a human to approve before submission. That last step matters. HMRC still holds the business owner accountable, so exception handling and human-in-the-loop approval are not optional.

Deployed well, this cuts the time spent on each MTD quarter from a full day of catch-up to a short review session, and it makes April 2027's £30,000 threshold expansion far less disruptive when it lands.

What happens if you ignore the auto-enrolment letter?

Ignoring the letter does not remove the obligation. Digital record-keeping and quarterly filing become due from the effective date HMRC sets, and any tax owed still attracts interest. Late self assessment penalties continue to apply during the 2026/27 grace period. Prepare now, or plan to spend Q4 catching up in a hurry.