Keeping track of important tax dates for small businesses in the UK is crucial to avoiding penalties and ensuring smooth financial operations. Missing these deadlines can result in fines and interest charges – both unnecessary stress for your business. It doesn’t matter whether you’re a sole trader, partnership, or limited company. Understanding when you need to submit returns and make payments to HMRC is an essential part of business management.
At Professional Saver, we know that tax compliance can be complex for busy professionals and small business owners. With our 40 years of experience providing insurance solutions specifically tailored for professionals, we recognise that staying on top of tax obligations is just one of many responsibilities you juggle. That’s why we’ve created this comprehensive guide to help you mark these critical tax dates in your calendar and plan your cash flow accordingly.
When Does the UK Tax Year Run?
The UK tax year doesn’t follow the calendar year. Instead, the standard tax year in the UK runs from 6 April to 5 April the following year. This somewhat unusual timeframe has historical origins but remains the foundation of the UK tax system.
For self-employed individuals and partnerships, this tax year (6 April to 5 April) is the period for which you’ll report your income and expenses on your Self Assessment tax return. However, a limited company’s accounting period is based on its Accounting Reference Date (ARD), which was initially set by Companies House.
What Are the Key Self Assessment Deadlines?
Self Assessment tax returns are required for self-employed individuals, business partners, and directors of limited companies. The main deadlines you need to remember are:
| Deadline | Requirement |
| 5 October | Register for Self Assessment if you’re newly self-employed or received untaxed income |
| 31 October | Paper tax return submission deadline |
| 31 January | Online tax return submission deadline |
| 31 January | Deadline for paying tax owed for the previous tax year |
| 31 January | First payment on account for the current tax year |
| 31 July | Second payment on account for the current tax year |
Data extracted from GOV.UK
For example, for the 2023/24 tax year (which runs from 6 April 2023 to 5 April 2024), you would need to:
- Submit your Self Assessment tax return by 31 January 2025
- Pay any tax owed for 2023/24 by 31 January 2025
- Make your first payment on account for 2024/25 by 31 January 2025
- Make your second payment on account for 2024/25 by 31 July 2025
How Do VAT Return Deadlines Work?
If your business is VAT-registered (mandatory if your taxable turnover exceeds £85,000), you’ll need to submit VAT returns regularly. Most businesses submit quarterly VAT returns, though some may opt for monthly returns or use the Annual Accounting Scheme.
Your specific VAT return deadlines depend on when you registered for VAT. Typically, you must submit your VAT return and make payment within one month and seven days after the end of your VAT period. With Making Tax Digital for VAT now in force, most businesses must submit returns using compatible software.
Here’s an example for a business with standard quarterly VAT periods:
| Quarterly Dates | VAT Payment Dates |
| Quarter ending 31 March | VAT return and payment due by 7 May |
| Quarter ending 30 June | VAT return and payment due by 7 August |
| Quarter ending 30 September | VAT return and payment due by 7 November |
| Quarter ending 31 December | VAT return and payment due by 7 February |
What Are the Corporation Tax Deadlines for Limited Companies?
Limited companies face different tax deadlines compared to sole traders. For corporation tax, there are two key dates to remember:
- Filing your Company Tax Return – Due 12 months after the end of your accounting period
- Paying your Corporation Tax bill – Due 9 months and 1 day after your accounting period ends
For example, if your company’s accounting period ends on 31 March 2024:
- Your Company Tax Return would need to be filed by 31 March 2025
- Your Corporation Tax payment would be due by 1 January 2025
Additionally, limited companies must file annual accounts with Companies House within 9 months of their financial year-end. For private limited companies, if your accounting period ends on 31 March 2024, your accounts must be filed with Companies House by 31 December 2024.
What Are the Key PAYE and National Insurance Deadlines?
If you employ staff, you must make PAYE (Pay As You Earn) and National Insurance contributions to HMRC. The main deadlines are:
| Payments | Deadlines |
| Monthly payments | You must pay PAYE and National Insurance to HMRC by the 22nd of the month after you made the deductions. |
| Full Payment Submission (FPS) | You must submit FPS to HMRC on or before each payday. |
| Employer Payment Summary (EPS) | If required, you must submit EPS by the 19th of the following month. |
| P60 forms | You must give P60 forms to employees by 31 May after the tax year ends. |
| P11D forms | You must submit P11D forms to HMRC by 6 July after the tax year, with any Class 1A National Insurance due by 22 July. |
Are There Other Important Tax Dates I Should Know?
Beyond the main tax deadlines, several other important dates may apply to your small business:
Capital Gains Tax Reporting and Payment
Residential Property Sales
UK residents selling residential property with a capital gain must report and pay within 60 days of completion if the disposal occurs on or after 27 October 2021. For disposals between 6 April 2020 and 26 October 2021, the deadline was 30 days.
Non-residents must report all UK residential property disposals (even if no tax is owed) within 60 days of completion.
Other Assets
Capital Gains Tax for non-residential assets (e.g., shares, commercial property) is reported through your Self Assessment tax return and paid by the 31 January deadline.
Making Tax Digital (MTD)
The government’s MTD initiative is being phased in:
- VAT-registered businesses – Already implemented and required to use MTD.
- Income Tax Self Assessment –
- April 2026 – Applies to businesses/landlords with gross qualifying income (self-employment/property) over £50,000.
- April 2027 – Applies to those with gross qualifying income over £30,000.
- Exemptions – Businesses with qualifying income ≤£30k (2026) or ≤£50k (2027) are exempt.
- Corporation Tax – No confirmed implementation date yet.
Construction Industry Scheme (CIS)
If you work in the construction industry, you must submit your monthly CIS returns by the 19th of each month. For CIS deductions, postal payments are due by the 19th, and electronic payments should be made by the 22nd.
How Can I Stay on Top of My Tax Obligations?
Managing tax deadlines effectively requires organisation and forward planning. Try these practical tips:
- Create a tax calendar – Mark all relevant deadlines in your business calendar with reminders set several weeks in advance.
- Maintain organised records – Keep your financial records up-to-date throughout the year to make tax returns easier.
- Set aside tax funds – Regularly set money aside for tax payments to avoid cash flow problems.
- Consider accounting software – Use software that tracks deadlines and integrates with HMRC systems.
- Work with a qualified accountant – Professional advice can save you money and ensure compliance.
- Register for HMRC reminders – HMRC can send you email alerts about upcoming deadlines.
Missing tax deadlines can lead to penalties starting at £100, which increase the longer you delay. You’ll also be charged interest on late payments, and repeated delays can result in even more penalties.
Getting Support with Your Business Tax Obligations
Understanding and meeting your tax obligations is crucial to running a successful small business in the UK. By marking these key dates in your calendar and planning accordingly, you can avoid unnecessary penalties and focus on growing your business.
At Professional Saver, while we specialise in providing comprehensive insurance solutions for professionals starting from just £59 annually, we understand the broader challenges of running a business. Our insurance packages can be tailored to protect your business assets and liabilities, giving you one less thing to worry about as you navigate your tax responsibilities.
Don’t risk falling behind. Get a quote from Professional Saver today and ensure your business stays on track.
