Quick answer:
Self-employed tax is due on 31 January (your balancing payment plus the first payment on account) and 31 July (the second payment on account), with your tax return or MTD final declaration due by 31 January, and under Making Tax Digital you also file four quarterly updates during the year, though the tax payment dates stay the same.
Knowing the calendar is half the battle. Here’s every date that matters.
The core self-employed tax dates
| Date | What’s due |
| 31 January | Balancing payment for the previous tax year + first payment on account + return/final declaration deadline |
| 31 July | Second payment on account |
| 5 October | Deadline to register if newly self-employed |
| 6 April | Start of the new tax year |
When is your tax return due?
Under the old system, your Self Assessment return is due by 31 January following the tax year. Under MTD, this is replaced by the final declaration, also due 31 January, see Self Assessment to MTD transition.
What changes under MTD?
The payment dates don’t change, you still pay on 31 January and 31 July. What’s new is that you file four quarterly updates during the year (due 7 August, 7 November, 7 February and 7 May) on top of the final declaration. See the full schedule in MTD deadlines and timeline.
Don’t forget payments on account
The 31 January and 31 July payments include payments on account, advance payments towards next year’s bill. This is why January can be bigger than expected. See payments on account explained.
How much should you have ready?
Knowing the dates is one thing; having the money is another. A real-time tax estimate tells you what to set aside as you go, see how much tax to set aside and protect the cash with real-time cash flow forecasting.
How CleanBooks AI keeps you on schedule
CleanBooks AI tracks your quarterly windows and keeps a live tax estimate, so both your filing dates and your payment amounts are visible well ahead. Keeva™ flags what’s coming up, turning the tax calendar from a source of stress into a solved problem.
Never miss a tax date again. Stay on track with CleanBooks AI free, 6 months free, no credit card.