UK Tax Calendar: Key Dates Every Business Should Know
Staying on top of your tax obligations is essential for running a compliant and successful business in the UK. Missing deadlines can result in penalties, interest charges, and unnecessary stress. Whether you’re a sole trader, limited company, or VAT-registered business, understanding the key tax dates throughout the year helps you stay organised and avoid last-minute scrambles.
Here’s a breakdown of the most important UK tax dates to add to your calendar.
31 January – Self Assessment Tax Return & Payment Deadline
This is the deadline to:
- Submit your online Self Assessment tax return for the previous tax year (ending 5 April)
- Pay your Income Tax, National Insurance, and first payment on account (if applicable)
Miss this deadline and you could face a £100 penalty, plus interest on any outstanding tax.
5 April – End of the Tax Year
The UK tax year runs from 6 April to 5 April the following year. On 5 April, the current tax year ends, and the new one begins the next day.
This date marks a good opportunity to:
- Finalise pension contributions
- Maximise tax allowances
- Prepare for your upcoming tax return
6 April – Start of the New Tax Year
New tax rules, thresholds, and rates often come into effect on this day. It’s a good time to review your payroll settings, personal allowances, and business strategy for the year ahead.
31 July – Second Payment on Account Due
If you’re self-employed or pay tax via Self Assessment, and your previous year’s bill was over £1,000, you’ll usually need to make two advance payments toward your next tax bill.
The second payment on account is due by 31 July.
5 October – Deadline to Register for Self Assessment
If you’ve started a new business or received untaxed income for the first time in the last tax year (ending 5 April), you must register with HMRC for Self Assessment by 5 October.
31 October – Paper Tax Return Deadline
If you prefer to file a paper tax return, the deadline is earlier—31 October. This applies to Self Assessment returns for the previous tax year.
Filing late can result in automatic penalties.
1 April – Corporation Tax Payment Deadline (Most Companies)
Most UK companies with a year-end of 31 March must pay Corporation Tax by 1 April of the following year.
Note: The exact deadline depends on your company’s accounting period. Corporation Tax is due nine months and one day after your accounting year ends.
Company Accounts and Confirmation Statement Deadlines
Limited companies also have two key annual deadlines:
- Company accounts: Due 9 months after your company year-end
- Confirmation statement: Must be filed at least once every 12 months, typically on the anniversary of incorporation
Missing these can lead to fines and even company dissolution.
Quarterly VAT Return Deadlines
If you’re VAT registered, you’ll need to submit VAT returns every quarter. The deadline is usually one month and seven days after the end of the VAT period. You must also pay any VAT owed by this date.
Final Thoughts
Managing tax deadlines can be complex, especially when juggling multiple obligations. Using accounting software or working with an accountant can help ensure you never miss a date. Add these key milestones to your calendar, set reminders, and plan ahead to avoid penalties and stay financially healthy.
