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Corporation Tax return

[CONTENT REVIEW] A Company Tax Return reports the company's taxable profit or loss and Corporation Tax calculation to HMRC.

Last checked:

This is the date the official sources were checked, not an approval date.

Who needs to do this, and who is responsible?

[CONTENT REVIEW] A company or association receiving a notice to deliver a return must file, even if it made a loss or owes no tax. Company directors retain legal responsibility even when an accountant files.

When is it due?

[CONTENT REVIEW] The filing deadline is 12 months after the accounting period ends. Payment has a separate deadline, usually nine months and one day after that period.

How ComplyClock calculates deadlines

What does it cost?

[CONTENT REVIEW] Budget for any filing software or accountant charges. The Corporation Tax bill is a separate payment.

What you need

  • [CONTENT REVIEW] Accounts and calculations of taxable profit or loss and Corporation Tax.
  • [CONTENT REVIEW] Software that supports the return and required attachments, or an accountant who can file it.

How to do it

  1. [CONTENT REVIEW] Confirm the accounting period and HMRC's notice to file.
  2. [CONTENT REVIEW] Prepare the return, tax calculation and required accounts attachments.
  3. [CONTENT REVIEW] File using commercial software. The joint HMRC accounts and tax-return service closed on 31 March 2026; paper exceptions remain for a reasonable excuse or Welsh filing.

What happens if it is late?

[CONTENT REVIEW] Missing the filing deadline attracts a penalty. Filing the return does not settle the separate tax bill.

Official guidance

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