MTD Quarterly Deadlines 2026: Every Submission Date You Need to Know

If you are required to use Making Tax Digital for Income Tax (MTD ITSA) from 6 April 2026, you will need to submit four quarterly updates to HMRC every tax year. Missing these deadlines can trigger penalty points. This guide sets out every deadline for the 2026-27 tax year, explains what each update must contain, and covers what happens if you miss one.

What Is a Quarterly Update?

Under MTD ITSA, you no longer submit a single annual Self Assessment return for your self-employment or property income. Instead, your compatible software summarises your income and expenses every three months and sends the totals to HMRC.

You do not need to calculate your tax liability or make accounting adjustments before sending. Your software does the summarising. HMRC then uses the figures to show you an estimate of your tax bill in your online account.

Each update covers the period from the start of the tax year to the end of the quarter. Your third update, for example, will include corrections you have made to earlier periods as well as new records for that quarter.

If you have more than one source of qualifying income (for example, one self-employment business and one rental property), you must submit a separate set of quarterly updates for each source.

The Four Quarterly Deadlines for 2026-27

HMRC confirmed the quarterly submission deadlines on GOV.UK. The deadlines apply to the standard update periods, which align with the tax year (6 April to 5 April).

Important: If you are currently testing MTD ITSA voluntarily, your HMRC online account may still show the fifth of the month as the deadline. HMRC has confirmed this will update to the seventh ahead of 6 April 2026.

After Q4, you will also need to finalise your Income Tax position and submit a final declaration by 31 January 2028. The final declaration replaces the traditional Self Assessment tax return.

Calendar Update Periods: An Alternative

If your accounting period ends on 31 March rather than 5 April, you may be able to use calendar update periods instead. These end on the last day of the month and share the same deadlines as the standard periods.

You must select calendar update periods in your software before sending your first update of the tax year. You cannot switch mid-year.

What Each Quarterly Update Includes

Each update sends HMRC the cumulative totals of your income and expense categories from 6 April to the end of that quarter. HMRC does not receive a list of individual transactions, only category totals.

For example, your Q3 update (due 7 February) will include:

• Your records for 6 October to 5 January
• Any corrections you have made to records already sent in Q1 and Q2

If you had no income or expenses in a quarter, you still need to send the update to confirm this.

Can You Submit More Often?

Yes. Most compatible software allows you to send updates on any day, not just at the quarterly deadline. Some users prefer to submit monthly to track their tax estimate more closely.

Any additional update must cover the full update period to date. You cannot submit a partial period. HMRC also allows you to send an update up to 10 days before the end of the period if you know no further transactions will occur (for example, if you are going on holiday and your business will be inactive for the rest of the quarter).

Penalty Points for Late Quarterly Updates

HMRC operates a points-based late submission penalty system for MTD ITSA. Each missed quarterly deadline adds one penalty point to your record. When you reach a threshold of four points, HMRC issues a £200 fixed penalty.

Points expire after a period of compliance. The GOV.UK guidance confirms that once you have met all your obligations for a set period (12 consecutive months for quarterly filers) without further late submissions, your points balance resets to zero.

Grace period for Phase 1 (2026-27 only): HMRC has confirmed it will not apply penalty points for late quarterly updates during the first 12 months of mandatory compliance. This grace period covers the 2026-27 tax year for those required to join from 6 April 2026. Penalty points will still apply for late final declarations.

This does not mean you can ignore the deadlines. You must still submit all quarterly updates before you are able to file your final declaration.

What This Means for You

Add all four deadlines to your calendar now. The simplest way to stay compliant is to reconcile your records monthly and let your software generate the quarterly submission automatically when the period closes.

If you are not yet sure whether you need to comply from 6 April 2026, your obligation depends on your qualifying income for the 2024-25 tax year. Qualifying income is the total gross income from self-employment and property before deducting expenses. If it exceeded £50,000, you are in Phase 1. You can use the MTD eligibility checker on GOV.UK to confirm your position.

For a full overview of how MTD works, what software you need, and how to prepare, see our complete MTD ITSA guide.

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DigiTaxHub.co.uk is an independent information resource and is not affiliated with or endorsed by HMRC. This article is for information purposes only and does not constitute tax or financial advice. Always verify current rules at GOV.UK and speak to a qualified accountant if you are unsure.