Tax Deadlines Every UK Business Must Know (2026 Calendar for Surrey SMEs)

The importance of tax deadlines

Most tax problems don’t happen because a business owner “doesn’t pay tax”, they happen because deadlines creep up, cashflow is tight and the admin hasn’t been kept up to date. That’s why having a simple tax calendar is one of the best ways to stay compliant and avoid stress.

If you’re running a small business in Surrey, it’s easy to lose track of what’s due and when. Many business owners are juggling client work, staff, suppliers and growth decisions, so compliance slips into the background until something becomes urgent. The goal isn’t to obsess over deadlines, it’s to build a routine where deadlines are predictable, planned for, and never become a last-minute panic.

This guide gives you a clear overview of the key UK deadlines in 2026 and, more importantly, how to stay in control of them.

Why deadlines matter more than people think

Missing a deadline doesn’t just create a penalty. It usually triggers a chain reaction: rushed bookkeeping, inaccurate figures, missed claims and poor decisions because you’re working with numbers you don’t fully trust. Even when a penalty is small, the time cost and stress can be huge.

For VAT-registered businesses and limited companies especially, late filings can also create an impression of poor financial control which isn’t ideal if you ever need funding, finance or even a mortgage.

VAT deadlines (Making Tax Digital)

If your business is VAT registered, VAT returns are usually submitted quarterly (although this can vary under certain circumstances) and the filing and payment deadline is usually one month and seven days after the end of the VAT period.

VAT is one of the most common areas where businesses get caught out, not because VAT itself is complicated but because it relies on good bookkeeping. If sales invoices aren’t raised properly, receipts aren’t recorded or expenses are miscategorised, the VAT return can be wrong. That creates risk and can also mean you pay more VAT than necessary.

If you want VAT to feel easy, the key is keeping records current and making sure your bookkeeping software is set up correctly from the start.

PAYE and payroll deadlines (if you have staff)

If you employ staff or pay directors via payroll PAYE reporting becomes a monthly (or sometimes weekly/fortnightly) routine. Submissions are typically made through Real Time Information (RTI) and PAYE/NIC payments follow monthly deadlines.

Payroll errors can become expensive quickly, especially if pension auto-enrolment is involved. Even small mistakes can create employee issues, HMRC notices and time-consuming corrections. This is why businesses often outsource payroll once they have even a small team - it reduces risk and removes a major admin burden.

Corporation tax deadlines (limited companies)

Corporation tax deadlines depend on your accounting period end, but most limited companies will need to pay corporation tax within nine months and one day after the end of the accounting period (unless they are a larger company or have larger amounts of profits). The corporation tax return itself is normally due later but the payment date is the one that catches people out because it comes sooner than expected. To keep the corporation tax deadline simple, most accountants look to file the corporation tax return alongside the financial statements to ensure all compliance work is completed at the same time.

This is where planning matters. If you don’t keep an eye on profits throughout the year, it’s easy to reach the end of the year and realise your corporation tax bill is larger than expected. When that happens, businesses often pay late simply because the cash wasn’t set aside.

A good accountant will help you forecast the likely tax position and encourage you to ring-fence money monthly so there are no surprises.

Self Assessment deadlines (sole traders and directors)

If you’re a sole trader, landlord, or company director with personal income to declare, Self Assessment is an annual deadline. The problem with Self Assessment is that it often feels far away - until it suddenly isn’t.

The best way to avoid stress here is to treat Self Assessment as a “year-round task” rather than a January emergency. Keeping income and expenses organised, tracking dividends properly, and recording pension contributions throughout the year makes the final return quick and accurate.

Companies House deadlines (limited companies)

Companies House accounts must also be filed annually, and late filing can lead to penalties. This often happens when the accounts process is left too late, or when bookkeeping isn’t ready for the accountant to prepare the accounts properly.

If your records are up to date then accounts filing is usually straightforward. If they aren’t, it becomes a scramble and you lose time correcting basic issues rather than improving the business.

The easiest way to stay compliant without thinking about it daily

The best businesses don’t “remember deadlines”. They build a system where compliance happens naturally.

That system usually looks like:

- bookkeeping kept up to date monthly

- bank transactions reconciled regularly

- a simple monthly review of what you owe (VAT, PAYE, corporation tax)

- a plan for upcoming payments

Once that routine is in place, deadlines stop being stressful and start being predictable.

Want a deadline plan built around your business?

If you’re based in Surrey and want to stay fully compliant without the stress, Love Your Accountants can manage your deadlines and keep your bookkeeping and reporting under control throughout the year.

Book a free consultation and we’ll help you build a simple compliance routine that fits your business.