Most companies pay corporation tax 9 months after the end of their accounting period. However, companies with profits in excess of £1,500,000 a year are required to pay corporation tax on a quarterly basis. The first 25% is due 6 months and 14 days into the period, with subsequent 25% payments due every 3 months thereafter. This can be a serious cash flow issue in the first year that it applies, although there is a one year “grace” period. The £1.5 million limit is divided by the number of “associated” companies (under common control), so if there are 4 companies this limit is just £375,000. From 1 April 2015 this rule will only apply to members of a 51% group. We can help you plan to avoid this rule applying to your companies.