MTD Quarterly Update August 2026: What to Do Before the Deadline

Making Tax Digital for Income Tax went live in April 2026. The first quarterly deadline is now three months away. For most sole traders who enrolled in April, this is the moment to make sure everything is actually in place — not just planned.

This guide is about the August 2026 deadline specifically: what you need to submit, where you stand right now, and what to do if your records are not ready in time.

What is this submission and what does it involve?

A quarterly update is a digital summary of your business income and expenses for a three-month period, sent directly to HMRC via your MTD-compatible software. It is not a tax payment. It is a reporting obligation.

Your Q1 update covers 6 April to 5 July 2026. HMRC receives your income total and your expenses broken down by category. They use these figures to generate an in-year estimate of your tax position. The actual tax calculation happens at year end.

The submission itself takes minutes once your records are in order. The preparation is what takes time if you have left it.

The four 2026/27 deadlines

Quarter	Period	Deadline
Q1	6 April – 5 July 2026	7 August 2026
Q2	6 July – 5 October 2026	7 November 2026
Q3	6 October 2026 – 5 January 2027	7 February 2027
Q4	6 January – 5 April 2027	7 May 2027

Where you should be right now (May 2026)

By now — roughly seven weeks into the first MTD tax year — you should have:

• Chosen and connected MTD-compatible software to your HMRC Government Gateway account
• Set up your bank feed so transactions are importing automatically
• Been categorising income and expenses throughout April and May

If any of these are not in place, you have time to fix it before August — but not much time to waste.

If you have software set up and records running

You are in good shape. Before 7 August, review your Q1 transactions (April, May, June), make sure everything is categorised, and submit through your software when the July period closes. Most software has a clear "submit quarterly update" workflow.

If you enrolled in MTD but have not set up software yet

You need to act now. You cannot submit through HMRC's old Self Assessment portal. You need MTD-compatible software connected to your Government Gateway account. FreeAgent, QuickBooks, Xero, and Sage are all HMRC-recognised options. All offer free trials. Setup takes a few hours including connecting your bank feed and importing historical transactions.

If you bank with NatWest, RBS, Ulster Bank, or Mettle, FreeAgent is included free — activate it through your business banking portal.

If your records are incomplete or behind

Gather your bank statements for April onwards and import or enter the missing transactions. Your software should allow CSV import if your bank supports it. Categorise everything. You have until 7 August — use the time.

How to actually submit (the process in software)

The exact steps vary by software, but the pattern is consistent across all HMRC-recognised platforms:

1. Ensure all transactions for the quarter are entered and categorised
2. Open the MTD or quarterly update section in your software
3. Review the income and expense summary your software has compiled
4. Confirm the figures look correct
5. Click submit — your software sends directly to HMRC via their API
6. Save the submission confirmation reference

There is no separate HMRC portal step. If your software is properly connected, the submission is entirely within the software.

What HMRC does with your submission

After your quarterly update is received, HMRC issues an in-year tax estimate. This is not a bill — it is an estimate. It is calculated on the assumption your current quarterly income and expense run rate continues for the year.

Do not pay tax based on this estimate unless your accountant advises you to. The actual tax due is confirmed through the End of Period Statement and Final Declaration at year end.

What comes after Q1

After August, your next deadline is 7 November for Q2 (6 July – 5 October). The quarterly rhythm continues through the year. At year end you will also complete an End of Period Statement and a Final Declaration, which replaces the traditional Self Assessment return.

The quarterly submissions feed into the year-end process — the more accurate and timely they are, the easier the final declaration is.

For a full walkthrough of the Q1 submission process, see our step-by-step quarterly update guide. For what happens if you miss the deadline, see our guide to MTD penalty points.