Limited companies

Corporation Tax for UK limited companies: rates, deadlines and what to file

Your CT600 is due 12 months after the year-end. The tax is usually payable nine months and one day after. Get the dates in the diary before the accounts are even drafted.

Two rates, one company

Most small companies still see a 19% small profits rate on profits up to £50,000 and a 25% main rate above £250,000, with marginal relief in between. Associated companies can reduce those thresholds, so group structures need a proper look — not a guess.

The two clocks

Corporation Tax is usually payable nine months and one day after the end of the accounting period. The CT600 return is due 12 months after. Missing the payment date costs interest; missing the return can mean penalties even if you have paid.

Accounts still go to Companies House (typically nine months after year-end for private companies). Those figures and the CT600 need to tell the same story.

What we actually prepare

Year-end accounts, the CT600, corporation tax computations, and a short explanation of the bill — including capital allowances, R&D if it genuinely applies, and director’s loan accounts if they have drifted. Read more on Corporation Tax and accounts & bookkeeping.

This article is general information for UK readers, not personal tax advice. Rules change. Check GOV.UK or speak to us before you file.

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