16/10/2026
If you own more than one company, the corporation tax thresholds are not what you think they are.
The £50,000 and £250,000 limits that decide whether you pay 19%, 25% or land in the 26.5% marginal band are divided by the number of associated companies.
Two companies, and the limits become £25,000 and £125,000 each. Three, and it is £16,667 and £83,333.
So a company making £30,000 of profit pays 19% if it stands alone, and drops into the marginal band the moment there is a second company in the picture.
The trap is that associated is wider than owned. Companies under common control count, and control can come through people connected to you as well as through you. A company your spouse controls can be associated with yours even if you have never had anything to do with it.
Two common cases that catch people.
The dormant company nobody closed after the last venture. Dormant companies are generally ignored for this, but only if they are genuinely dormant throughout.
The property company set up beside the trading company. Usually associated, usually a surprise.
If you have more than one company and nobody has ever checked this with you, it is a fifteen minute job to find out and it can be worth thousands.
Reply to this if you want to know how to check.