Quick answer
Make sure every income and expense for the period is in your software with an amount, date and category. Review the summary your software prepares, then submit it to HMRC by the 7th of the month after the quarter ends. HMRC then shows you an estimate of your tax for the year.
Step by step
Check your software is connected to HMRC and shows all your income sources.
Make sure every transaction for the period is in your software.
Give each one a category and attach receipts.
Review the summary for anything that looks wrong.
Submit the update. You’ll need one for each business and property source.
Check HMRC has received it, and note the tax estimate.
Deadlines
Updates are due on 7 August, 7 November, 7 February and 7 May. In 2026/27 there are no penalty points for late updates, but you still need to send them before your final declaration.
Common first-time problems
An income source missing from your HMRC account: add or correct it before submitting.
Uncategorised transactions: these can distort the summary.
Personal spending in a business account: exclude it or record it correctly.
Made a mistake? See how to correct an MTD update.