Key Dates Small Businesses Need to Know

Meeting tax and reporting deadlines is essential for any business, whether you're self-employed or running a company. HM Revenue and Customs (HMRC) and Companies House require timely submissions. Missing these deadlines can lead to fines, penalties, and interest charges.

Staying on top of key dates is especially important for tax filings, payroll submissions, and financial reporting, as delays can cause cash flow issues and unnecessary stress. To help you stay organised and compliant, here's a breakdown of the essential deadlines every small business should know.

Tax deadlines

Self-Assessment tax return

January 31—deadline for submitting your online Self-Assessment tax return for the previous tax year. Any outstanding tax must also be paid by this date. There's an automatic £100 penalty if you fail to send in a tax return by this date.¹

October 5—if you're newly self-employed, you must tell HMRC by this date if you need to complete a tax return and have not sent one before.²

July 31—the second payment deadline on account for those who make advance payments towards their tax bill.

Corporation Tax

Nine months and one day after your company's financial year-end—the deadline for paying Corporation Tax. For example, if your financial year ends on March 31, your payment is due by January 1 of the following year.³

12 months after your financial year-end—the deadline for filing your Company Tax Return with HMRC.

VAT deadlines

The deadline for submitting your return online is usually one calendar month and seven days after the end of an accounting period. This is also the deadline for paying HMRC. These deadlines will depend on your VAT return period and whether you file quarterly, monthly, or annually.⁴

For example, if your business follows calendar quarters (March, June, September, and December), the corresponding VAT return and payment due dates would be May 7, August 7, October 7, and February 7 for each quarter.

If your business is partially exempt, annual adjustments are typically included in the March or June returns, which would be due by May 7 or August 7.

Payroll and PAYE deadlines

• 22nd of each month—if you pay employees, Pay As You Earn (PAYE) and National Insurance contributions must be submitted to HMRC.⁵
• July 22—deadline for reporting employee benefits and expenses.⁶

Key financial and compliance deadlines

Confirmation statement

Every limited company must file a Confirmation Statement with Companies House at least once a year. The due date is usually within 14 days of your company's incorporation anniversary.⁷

Year-end accounts

If your business is a limited company, you must file annual accounts with Companies House within nine months of your financial year-end.⁸

Other key dates to consider

• April 5—end of the UK tax year. Consider tax planning before this date to maximise allowances and deductions.
• April 6—start of the new tax year, when new tax rates and thresholds may come into effect.
• March 26—the 2025 Spring Budget will not be a traditional budget. This year, an Economic and Fiscal Forecast will be published instead.
• From April 6 2026, Making Tax Digital will become mandatory for some businesses. This means VAT and income tax returns must be submitted digitally using compatible software.⁹

Why staying organised matters

Keeping track of these deadlines helps avoid penalties, ensures compliance, and keeps business operations running smoothly. Using accounting software, setting up reminders, or working with an accountant can help you stay on top of these critical dates.

Sources

1. gov.uk/self-assessment-tax-returns/deadlines 
2. gov.uk/register-for-self-assessment 
3. gov.uk/prepare-file-annual-accounts-for-limited-company 
4. gov.uk/vat-payment-deadlines 
5. gov.uk/pay-paye-tax 
6. gov.uk/pay-class-1a-national-insurance 
7. gov.uk/guidance/confirmation-statement-guidance 
8. gov.uk/prepare-file-annual-accounts-for-limited-company 
9. gov.uk/government/publications/making-tax-digital/overview-of-making-tax-digital