Tax Year Dates 24 25 for UK Businesses

Use our interactive calendar to stay on top of the key tax year dates which affect your business. We’ve outlined the kinds of charges you could face for missing the tax return deadline. However, to be eligible your tax bill must be less than £3,000 and you must file your online return by this date. The advantage of this is that any tax payable would be paid over according to analysts 12 months from April 2026, rather than a single lump sum by 31 January 2026. HMRC will send you a letter or email with a different deadline to send your tax return by – this will be 3 months from the date on the letter or email.

• We have an extensive library of resources designed for self employed freelancers and small business owners, like you, who want to get to grips with tax legislation.
• CIS deductions must be paid to HMRC by the 22nd (or the 19th if you’re paying by post) after the tax month ends.
• For more information about staying compliant with UK tax requirements, visit GOV.UK’s tax guidance or contact our team for personalised advice tailored to your situation.
• By this date, taxpayers must have completed their financial documentation in readiness to submit their tax returns to HMRC.

Stay Ahead of Your Tax Obligations

For all things Self Assessment, turn to the experts at GoSimpleTax. Accounting Excellence award winners, their software makes completing a Self Assessment tax return straightforward. You can start using it to input your income and expenditure for free too—you only need to upgrade your account when you’re ready to submit your tax return directly to HMRC. First things first, you can’t file a tax return if you don’t know what period your tax return covers. In the UK, the tax year runs from 6th April to 5th April, which means all income and expenses in this time frame need to be reported in the next tax year.

If you’re late submitting your tax return or paying your tax bill, you’ll usually receive a penalty from HMRC. We’ve put together a calendar to help you stay on top of the key tax year dates which apply to your business. These deadlines are the latest dates you should take action to avoid penalties, but there might be times when acting earlier is better for your business! If you’re one of our clients, we’ll send reminders to let you know when important deadlines are on the horizon. You’ll also have your own personalised tax and reporting timeline in Client Hub, so you’ll always know exactly what to do, and when. If you miss the deadline for filing your paper tax return, don’t be tempted to try and file it late.

What happens if I miss the Self Assessment submission date?

For more information about staying compliant with UK tax requirements, visit GOV.UK’s tax guidance or contact our team for personalised advice tailored to your situation. We work with businesses across North London, helping them navigate the UK tax system efficiently. An additional £300 fine, or 5% of the tax due, plus the above penalties. You could face a £100 fine for filing even just a day after the deadline. You can use this to complete your own bookkeeping, or we can provide a quote to complete your bookkeeping for you. This document shows how much tax they paid on their salary in the preceding tax year.

All you have to do is register for Self Assessment on the GOV.UK site and wait to receive your Unique Taxpayer Reference (UTR) number and Government Gateway ID. This can take up to 10 days, so bear that in mind if you want to submit a paper tax return. However, if you receive a notice from HMRC that you must file a tax return after 31 July 2025, you’ll need to send back the completed form within three months of the date issued on the notice. The last tax year started on 6 April 2024 and ended on 5 April 2025. The deadline for earlier tax returns has passed and you may have to pay a penalty. Send your tax return or payment as soon as possible to avoid further penalties.

Remember, both these timescales are subject to tax refund checks, and so could take a little longer if your financial affairs are pretty complicated. They have a free number you can call, and will provide basic advice or any details you may have misplaced, like your tax code. They can get incredibly busy, especially around January, making it sometimes difficult to get the level of support you need.

For most individuals, this is the period HMRC uses to calculate their total earnings in order to determine what rate of tax they pay for the year, as well as their eligibility for allowances and reliefs. Some businesses, such as sole traders, use this as the basis for their financial reporting, and any changes to tax rates and allowances normally take place at the start of a new tax year. Understanding the UK tax year is crucial for both individuals and businesses. Missing key deadlines can result in penalties and interest charges from HMRC. This guide breaks down everything you need to know about the tax year in simple terms, helping you stay compliant and avoid unnecessary costs. There’s typically a second payment deadline of 31st July if you make advance payments towards your bill.