Making Tax Digital 2026: Key Dates and Deadlines You Cannot Afford to Miss

Published on: 15 Dec 2025Updated on: 30 Jun 20267 min read

Making Tax Digital for Income Tax replaces one annual Self Assessment return with four quarterly updates and a year-end Final Declaration. The reporting calendar is fixed: quarterly updates fall on 7 August, 7 November, 7 February and 7 May, and the Final Declaration is due on 31 January following the tax year.

This page sets out every date in one place: what is due, when it is due, and what happens if you miss it.

Are You Mandated? Check Your Threshold First

Before the deadlines mean anything, you need to confirm whether they apply to you. HMRC determines your mandation date from the qualifying income reported on your most recent Self Assessment return before your phase begins.

Qualifying income is gross turnover from self-employment and UK or foreign property combined, before any expenses, allowances, or deductions. Employment income, pension, dividends, interest, and capital gains do not count.

Phase 1: Qualifying income over £50,000

Mandatory from 6 April 2026. Assessed on your 2024/25 Self Assessment return

Phase 2: Qualifying income over £30,000

Mandatory from 6 April 2027. Assessed on your 2025/26 Self Assessment return

Phase 3: Qualifying income over £20,000

Mandatory from 6 April 2028. Assessed on your 2026/27 Self Assessment return

Not receiving a letter from HMRC does not mean you are exempt. The duty to check and comply rests with you.

Your Four Quarterly Update Deadlines

HMRC requires four quarterly updates per tax year, each summarising your income and expenses for that period.

Unless you actively choose otherwise, HMRC assigns you to the standard tax year quarters by default, with deadlines tied to fixed dates.

Standard tax year quarters (default)

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

These apply automatically if you make no active choice.

Calendar quarters (optional election)

Quarter	Period	Deadline
Q1	1 April to 30 June	7 August
Q2	1 July to 30 September	7 November
Q3	1 October to 31 December	7 February
Q4	1 January to 31 March	7 May

The deadlines are identical. The only difference is the dates each quarter covers. You must elect calendar quarters through your software before submitting your first update — it cannot be changed mid-year.

Multiple Income Source

If you have both self-employment and property income, each source requires its own separate quarterly update. All UK property, across multiple properties, is combined into one property update stream.

The Final Declaration: 31 January 2028

After four quarterly updates for the 2026-27 tax year, you submit a Final Declaration by 31 January 2028. This replaces the Self Assessment return and goes through MTD software, as HMRC's online filing route is not available to MTD users.

The Final Declaration is where you confirm all income across the year, correct any provisional quarterly figures, claim allowances and reliefs, and include non-qualifying income such as employment, dividends, or capital gains.

Do not confuse these two dates

31 January 2027 is also a deadline — but for your final traditional Self Assessment return for the 2025/26 tax year. That is the last time you file under the old system. The MTD Final Declaration takes over from 31 January 2028.

When You Pay: MTD Does Not Change This

MTD changes your reporting schedule, not your payment dates. Tax is still due on:

31 January: balancing payment for the previous tax year, plus first payment on account for the current year
31 July: second payment on account for the current year

Quarterly updates do not trigger any payment. Your tax bill is settled at 31 January and 31 July, exactly as before. Payments on account are also excluded from the new late payment penalty regime.

Penalties: What Happens When You Miss a Deadline

The soft landing — 2026/27 quarterly updates only

HMRC will not issue penalty points for late quarterly updates during the 2026/27 tax year, for Phase 1 taxpayers in their first year. You must still submit the updates, as they are required before you can make your Final Declaration.

The soft landing does not cover:

Late Final Declaration — full penalties apply from day one
Late payment of tax — the tiered payment penalty regime applies immediately
Phase 2 or Phase 3 taxpayers — they receive no soft landing when they join

Penalties for late submission

Each missed quarterly update or Final Declaration earns one point, and both sit in the same total. Four points brings a £200 charge, with a further £200 for each late submission after that.

Late payment is charged separately and applies to your balancing payment, not your payments on account.

The one easement to know is that 2026-27 gives you 30 days from the due date to pay or agree a payment plan before any penalty starts, dropping to 15 days from 2027-28.

After that, the charges rise in stages and interest runs from the first day the payment is late.

The full points regime, including how points expire and the reset conditions, is set out in our guide to MTD penalties and how they are calculated.

Every Key Date at a Glance: 2026 to 2029

Date	Event
6 April 2026	Phase 1 mandation begins (over £50,000)
7 August 2026	Q1 update due
7 November 2026	Q2 update due
31 January 2027	Final Self Assessment for 2025/26
7 February 2027	Q3 update due
7 May 2027	Q4 update due
6 April 2027	Phase 2 mandation begins (over £30,000)
7 August 2027	Q1 update due (2027/28)
7 November 2027	Q2 update due
31 January 2028	Final Declaration for 2026/27 due
7 February 2028	Q3 update due
7 May 2028	Q4 update due
6 April 2028	Phase 3 mandation begins (£20,000 or more)
7 August 2028	Q1 update due (2028/29)
31 January 2029	Final Declaration for 2027/28 due

Conclusion

The reporting calendar runs on fixed dates every year: four quarterly updates, one Final Declaration, and a points system that applies to both. The 2026-27 soft landing covers late quarterly update points only.

The Final Declaration and any late payment carry penalties from day one, so the dates to protect first are 31 January and the four quarterly deadlines. Put them in your calendar and set your software to file against them.

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Frequently Asked Questions

6 answers · curated

What is the very first MTD deadline I need to hit?

For Phase 1 taxpayers mandated from 6 April 2026, the first quarterly update covers 6 April to 5 July 2026 and is due by 7 August 2026. No penalty points apply if you miss it in 2026/27 due to the soft landing, but you must still submit it — HMRC requires all four quarterly updates to be filed before you can make your Final Declaration.

Do I still need to file a Self Assessment in January 2027?

Yes. The 31 January 2027 deadline is for your 2025/26 Self Assessment tax return — the final one filed under the old system. It is entirely separate from your MTD obligations. Your first MTD Final Declaration, covering 2026/27, is due on 31 January 2028.

Does MTD change when I pay my tax?

No. MTD changes how and how often you report your income, not when you pay. The 31 January and 31 July payment dates remain the same as under Self Assessment. Quarterly updates do not create any payment obligation.

What happens if I miss a quarterly update deadline?

In 2026/27, no penalty points are issued — that is the soft landing period. From 2027/28, each missed quarterly deadline earns one penalty point. Four points trigger a £200 fine, with a further £200 for every subsequent late submission after that.

Is the Final Declaration the same as my old Self Assessment return?

The deadline is the same — 31 January following the end of the tax year. But what you submit and how you submit it are different. The Final Declaration is made through your MTD software only. It pulls together your four quarterly updates, any corrections, all non-business income, and your claims for reliefs and allowances. HMRC's online filing route is no longer available to MTD users.

Can I switch between standard and calendar quarters?

Not mid-year. The election must be made through your software before submitting your first quarterly update of the tax year. Once your first update has been submitted, you are locked in for that year. You can switch at the start of the following tax year.