MTD Deadlines 2026: Quarterly Updates and Final Declaration

Under Making Tax Digital (MTD) for Income Tax, the old system of submitting one tax return every January is ending. Instead, you will need to interact with HMRC multiple times throughout the year.

Understanding the new deadlines is crucial to avoid penalty points and fines. Here is exactly what you need to know for the 2026/27 tax year.

When Does MTD Start?

The rules become mandatory based on your total gross income (income before expenses):

• 6 April 2026: Mandatory for sole traders and landlords with an income over £50,000.
• 6 April 2027: Mandatory for those with an income over £30,000.

The Quarterly Update Deadlines

Instead of an annual return, you must submit a summary of your business income and expenses every three months. These are known as quarterly updates.

For the standard tax year (running from 6 April to 5 April), the quarterly update deadlines are fixed. You have one month from the end of the quarter to submit your update.

Here are the deadlines for the 2026/27 tax year:

• Quarter 1 (6 April to 5 July): Deadline is 7 August 2026
• Quarter 2 (6 July to 5 October): Deadline is 7 November 2026
• Quarter 3 (6 October to 5 January): Deadline is 7 February 2027
• Quarter 4 (6 January to 5 April): Deadline is 7 May 2027

The Final Declaration Deadline

After you have submitted your four quarterly updates, you must submit a Final Declaration. This process replaces the traditional Self Assessment tax return.

During the Final Declaration, you will confirm that your quarterly updates are correct, add any other sources of income (like savings interest), and claim any tax reliefs.

• Final Declaration Deadline: For the 2026/27 tax year, your Final Declaration is due by 31 January 2028.

Paying Your Tax Bill

The deadline for actually paying your tax bill has not changed under MTD.

• Payment Deadline: You must pay your tax bill for the 2026/27 tax year by 31 January 2028.

If you make Payments on Account, those deadlines (31 January and 31 July) also remain the same.

How to Stay on Track

With five separate submission deadlines throughout the year, it is easy to lose track. The best way to stay compliant is to use simple software that reminds you when a deadline is approaching.

If you use spreadsheets to track your finances, bridging software like Abridge can connect your spreadsheet to HMRC and help you manage these new quarterly deadlines without the stress.