If you’re moving to the UK and planning to continue or start your sole trader business here, one of the first decisions you’ll need to make is: What accounting year end date should I choose?
You may have heard that the UK tax year runs from 6 April to 5 April – yes, it’s an unusual date, and we’ve put together a separate guide if you’d like to know the quirky historical reason why.
But history aside, what matters most is how your year end date affects your tax reporting and compliance obligations under the UK rules — especially under the new Making Tax Digital for Income Tax (MTD for ITSA) rules that are being rolled out.
The UK tax year starts on 6 April and ends on 5 April the following year. Your annual Self Assessment tax return is due by 31 January after the tax year ends, along with any balancing tax payment. In addition, under Making Tax Digital, you’ll also need to send quarterly updates to HMRC via approved software.
Choosing an accounting year end that aligns with the UK tax year will make your reporting easier, reduce the need for estimates, and help avoid unnecessary accountancy costs.
For tax purposes, HMRC treats any year end from 31 March to 5 April as aligned with the UK tax year.
Many of our overseas clients come from countries where a 31 December year end is standard. But in the UK, this can create complications. If your business accounts don’t end between 31 March and 5 April, HMRC will require you to:
Which can result in:
All of this can be avoided by simply choosing a 31 March year end when you register with HMRC.
If you’re just starting your UK business, set a 31 March year end right from the start.
If you’re already trading in the UK and using another year end, don’t worry — we can help you manage the transition under HMRC’s Basis Period Reform rules.
Sometimes it may not be possible to align your UK year end to 31 March — for example, if your business is required to report on a calendar year basis in your home country. In those cases, we can still support you with:
However, it’s important to be aware that your UK tax reporting will be more complex and there will likely be increased fees due to the extra calculations and filings required.
Filing the confirmation statement is legally the directors’ responsibility. Using a professional ensures:
| Deadline | What It’s For |
|---|---|
| 31 January (during the tax year) | First payment on account for current tax year |
| 31 July (after tax year end) | Second payment on account |
| 31 January (after tax year end) | Balancing payment + next year’s first payment |
| Quarterly MTD updates | Required throughout the year if MTD applies |
| 31 January (following tax year) | Deadline for submitting the Self Assessment |
We’ll help you stay on top of these dates, send reminders, and explain how and when to pay HMRC — including step-by-step guidance on making payments online.
We recommend using 31 March, as this aligns with the UK tax year and is treated by HMRC as equivalent to 5 April. It simplifies your tax reporting and helps avoid the need to use estimates or split profits across two accounting periods.
Yes, but it will make your UK tax reporting more complex. You’ll need to apportion profits between two sets of accounts and may need to file using estimated figures. We can help with this, but there may be additional accountancy fees.
The UK tax year runs from 6 April to 5 April. You file your tax return by 31 January following the end of the tax year, and pay your tax in instalments — usually in January and July.
No, but it is strongly advised if you want to keep your UK reporting simple. If your business needs to keep a different year end for home country reporting, we’ll help you manage the interaction between the two.
You may still be able to change it — or we can help you deal with the transitional rules if you’re affected by HMRC’s Basis Period Reform. We’ll ensure your filings remain compliant.
It means your business profits must now be reported in line with the UK tax year, not your own accounting year. If your accounting date doesn’t match the tax year, you’ll need to apportion profits and possibly use provisional figures.
HMRC allows provisional figures if your second set of accounts isn’t ready in time. You must later submit amended figures when they are available. We’ll help you manage this process and ensure your returns are updated correctly.
We work exclusively with clients from overseas, and we understand the challenges of adapting to the UK tax system. Choosing the right year end is a simple but important decision that can save you time, money, and stress later on.
Contact us today for a free consultation — we’ll explain what works best for your business and guide you through the process of getting set up with HMRC.
Senior Manager
Head of Direct Taxes
Senior Associate
Global Mobility, Personal Tax & VAT
