Your first MTD quarterly update is due 7 August 2026

First: check that this deadline is actually yours

The 7 August 2026 deadline applies to people using Making Tax Digital for Income Tax for the 2026/27 tax year. HMRC says the mandatory April 2026 cohort is generally based on qualifying income over £50,000 on the 2024/25 Self Assessment return. Volunteers may also be using the service.

Qualifying income is not total household income or PAYE salary. It is generally gross income from your self-employment and property sources before expenses and tax allowances. Exemptions and special cases can change the answer, so use HMRC's checker for the official decision.

What the first update covers

Your software will use one of two update-period patterns. For a tax-year accounting period, the first standard update covers 6 April to 5 July 2026. If your accounting period runs from 1 April to 31 March and you selected calendar updates in your software before the first submission, it covers 1 April to 30 June 2026. Both are due by 7 August.

HMRC now describes the updates as cumulative. The first update contains only the first period, but later updates run from the start of the tax year to the end of that later period. That lets corrected records flow into the next cumulative total without resending every earlier update.

What your software sends

A quarterly update is a summary, not a tax return. Compatible software totals the digital records for each self-employment or property business and sends the income and expense categories required by HMRC. You do not need to make accounting or tax adjustments before the quarterly update.

If you have more than one business, the process is organised by business rather than as one marketplace-wide bank total. Your software should show the sources and updates it expects. The annual tax return still comes later and includes the wider information, adjustments, reliefs and allowances needed to finalise the year.

A marketplace seller's pre-submission checklist

1. Confirm your start date. Check your HMRC position rather than relying on a platform notification or rough annual estimate.
2. Confirm the update period in your software. Calendar periods must be selected before the first update is sent.
3. Complete the digital records. Record income and expenses from the beginning of your applicable period, not only the weeks since you chose software.
4. Reconcile sales, refunds, fees and payouts. A net Amazon, Etsy, eBay or TikTok Shop deposit is not automatically the sales total for your records.
5. Keep each business source clear. Do not collapse unrelated self-employments or property income into a marketplace settlement figure.
6. Review the cumulative totals. Check for duplicate imports, missing refunds, personal transfers and fees recorded in the wrong category.
7. Send through compatible software. A spreadsheet can hold digital records, but it cannot submit directly unless compatible software connects it to HMRC.

The aim is not to calculate a final tax bill perfectly every quarter. It is to keep usable digital records and send the category totals the service requires. If your setup is complicated, ask your software provider, agent or a qualified tax professional before changing accounting treatment.

What happens if you miss 7 August

HMRC says it will not apply penalty points for late quarterly updates during the 2026/27 tax year. That is a first-year concession, not cancellation of the obligation. You still need to keep digital records and send the quarterly updates before you can submit the 2026/27 tax return through the service.

For later tax years, missing an update can create a late-submission penalty point. The published threshold is four points, followed by a £200 penalty and further £200 penalties for additional missed obligations while the threshold is active. Always check the current HMRC penalty guidance rather than assuming the first-year treatment continues.

What to do now

1. Use QuarterReady's threshold check if you are still unsure which published start-date band applies.
2. Open your software and confirm every expected business source and the selected period.
3. If you use a spreadsheet, follow the spreadsheet and bridging-software route.
4. Use the marketplace payout worksheet to separate sales, refunds, platform fees and net deposits before reviewing the totals.
5. Send the first update by 7 August 2026 where the deadline applies to you.