A Charitable Incorporated Organisation (CIO), which became available in October 2012, is a new corporate structure designed for charities. It provides an alternative to existing structures such as charitable companies (normally companies limited by guarantee), charitable trusts and unincorporated organisations.

CIOs are registered with and regulated by the Charity Commission (Commission) only and not with Companies House. They have registered charity status and, like any corporate structure, they have a separate legal personality allowing them to contract and hold property in their own name, as well as limited liability for its charity trustees and members. Its constitution must be in the form specified by regulations made by the Commission or as near to that form as circumstances permit.

Due to the single registration and reduced regulation and administration, the new CIO structure should appeal to charitable companies but it will also benefit unincorporated medium-sized charities which employ staff and/or enter into contracts. However, the lack of a Companies House style of register of charges means the structure will be less appealing to larger charities which regularly borrow money against the security of their property or raise money through issuing debentures. In addition, should the liability of the trustees not be an issue, the more straightforward structure of an unincorporated association or charitable trust may be preferable.