UK tax deadlines: the dates every small business must hit

The UK tax calendar is unusual in that half of it floats. Self Assessment and PAYE run on fixed dates tied to the 6 April to 5 April tax year; VAT and Corporation Tax move with each business’s own period ends. Missing either kind triggers penalties that are now points-based and automatic. Here is the full set of dates a typical UK small business has to hit, verified against the HMRC sources in the Sources section.

Self Assessment (sole traders, landlords, directors)

The online filing and payment deadlines coincide on 31 January ^[1] , which is why January is the cruellest month in every UK practice. Returns filed by 30 December can have tax of under £3,000 collected through a PAYE tax code instead ^[1] .

Since April 2026, sole traders and landlords mandated into MTD for Income Tax (qualifying income over £50,000) also send cumulative quarterly updates by 7 August, 7 November, 7 February, and 7 May ^[4] . The year-end return and payment dates above are unchanged. Our MTD for Income Tax guide covers the new cycle in full.

VAT

VAT deadlines are relative: the return and the payment are due one calendar month and 7 days after the end of the accounting period ^[2] . On a standard quarterly cycle:

Two sharp edges: the deadline does not move for weekends or bank holidays (the payment must have cleared) ^[2] , and direct debit collection happens a few days later automatically, so the safest setup for most small businesses is filing early with a direct debit in place.

Corporation Tax

Limited company deadlines hang off the company’s accounting period rather than the tax year, and they arrive in a counterintuitive order ^[3] :

Payment is due before filing. A company with a 31 March year end must pay by 1 January but has until the following 31 March to file. In practice the return needs preparing months early anyway, because the payment cannot be calculated without it.

PAYE (employers)

Employers who usually owe under £1,500 a month can ask HMRC to pay quarterly instead ^[5] .

The compliance rhythm, by business type

• A VAT-registered sole trader above the MTD threshold now has at least 9 fixed submission events a year: 4 VAT returns, 4 quarterly updates, 1 tax return. Before April 2026 it was 5.
• A small limited company with payroll runs monthly (RTI + PAYE payment), quarterly (VAT), and annually (CT600, accounts, and the director’s Self Assessment).

The practical consequence: record-keeping can no longer be batched into a year-end exercise. Each of those submission events draws on the same underlying books, and the books are only as current as the last receipt that made it in. That is the part ExpenseFlow automates: receipts and bills are captured as they happen, coded with the right VAT treatment, and synced into Xero or QuickBooks Online with the document attached, so each deadline starts from reconciled books rather than a backlog. The filings themselves happen from the accounting platform; ExpenseFlow keeps the data underneath them complete.