For CRC, undertakings such as companies, partnerships and unincorporated associations are grouped together using the tests in the Companies Act 2006. The definition of “undertaking” applies as set out in section 1161(1) of the Companies Act, but the definition is expanded in CRC to include unincorporated associations which carry out charitable activities. In some instances, CRC will bring together organisations that are not legally related. A vital first step is therefore to identify the group structure, including any franchise arrangements, joint ventures, private finance initiatives and landlord and tenant agreements.

CRC is restricted to UK energy use, but under the rules of CRC the group structure should be identified from the highest parent, even where it is overseas, to bring together all UK energy supplies in the entire group.