What is the current corporation tax rate?

The main rate of Corporation Tax is 25%, which applies to profits over £250,000. Companies with profits up to £50,000 pay the small profits rate of 19%, and profits between £50,000 and £250,000 are taxed at 25% but reduced by marginal relief, so the effective rate tapers gradually between the two. Your accountant can calculate your exact effective rate, especially if you have associated companies, which can affect where these thresholds sit for you.