Example

Worked example

Accounting period end date: 31 March 2026; Accounting period start date: 1 April 2025. Enter your own details to replace this example.

For accounts from 1 April 2025 to 31 March 2026, pay Corporation Tax by 1 January 2027 and file the CT600 by 31 March 2027. A private limited company must also deliver these accounts to Companies House by 31 December 2026. These dates assume the company doesn't pay its Corporation Tax by instalments.

Pay Corporation Tax by

1 January 2027

File the CT600 by

31 March 2027

File accounts at Companies House by

31 December 2026

• Large companies (taxable profits over £1.5 million) usually pay Corporation Tax earlier, in quarterly instalments. This calculator doesn't work out instalment dates.
• The period end is treated as the company's accounting reference date. If Companies House holds a different date, count from that date instead.
• Companies House deadlines still apply when they fall on a weekend or bank holiday.

Sources: GOV.UK: Pay your Corporation Tax bill · GOV.UK: Company Tax Returns · Companies House: Life of a company – accounts