§ Guide

Corporation Tax Registration: does it apply to you?

Finance Act 2008, Schedule 41 & Corporation Tax Act 2009

When this applies

You must tell HMRC your company is active within 3 months of starting to trade. This is a separate step from incorporating at Companies House, and it starts the clock even if your only activity so far is renting an office or employing your first member of staff, not necessarily a sale.

When it does not apply

Corporation Tax registration applies to limited companies. Sole traders and partnerships register for Self Assessment instead.

What is at stake

Failure-to-notify penalties under Schedule 41 Finance Act 2008 can reach 100% of the Corporation Tax due where the failure is deliberate and concealed. Coming forward unprompted before HMRC contacts you can reduce a non-deliberate late notification penalty to nil, so registering late is still far better than not registering at all.

What to do

Tell HMRC your company is active within 3 months of starting to trade, which includes advertising, employing staff, renting premises, buying, selling or earning any income, not just your first sale. Register online at gov.uk/set-up-limited-company/register-your-company-for-corporation-tax. This is separate from incorporating at Companies House and from filing your first Corporation Tax return.

Reviewed: 2026-09-13  ·  Source: official guidance