Corporation Tax
What it is
The tax a UK limited company pays on its profits, administered by HMRC. The company files a Company Tax Return (CT600) and pays the tax due for each accounting period.
Why it matters
The deadlines are unusual: the Corporation Tax is due 9 months and 1 day after your period ends, but the CT600 return isn't due until 12 months after. You must register for Corporation Tax within ~3 months of starting to trade.
Common mistake
Assuming the payment and the return share one deadline. They don't — the tax is due before the return.
Official source
GOV.UK — Corporation Tax ↗Disclaimer
General educational guidance only — not legal, tax, accounting, immigration, investment or financial advice. We don't guarantee the information is complete, current or suitable for your situation. Always check official sources (GOV.UK, Companies House, HMRC, the relevant professional body) and speak to a qualified professional before acting. Last reviewed: June 2026.