Voting members
- Bermuda Ombudsman
- Defence Forces Ombudsman, Ireland
- Energy Ombudsman
- Equality Tribunal
- Financial Ombudsman Service
- Financial Services Ombudsman Scheme for the Isle of Man
- Financial Services Ombudsman’s Bureau
- Garda Síochána Ombudsman Commission
- Gibraltar Ombudsman
- Housing Ombudsman Service
- Independent Police Complaints Commission
- Legal Services Ombudsman
- Local Government Ombudsman
- Northern Ireland Ombudsman
- Northern Ireland Police Ombudsman
- Office of the Ombudsman (Ireland)
- Parliamentary and Health Service Ombudsman
- Pensions Ombudsman
- Pensions Ombudsman of Ireland
- Property Ombudsman
- Public Service Ombudsman for Wales
- Removals Industry Ombudsman Scheme
- Scottish Public Services Ombudsman
- Surveyors Ombudsman Service
- Telecommunications Ombudsman (Otelo)
- The Ombudsman Serrvice Limited (tOSL)
- Waterways Ombudsman
Associate members
- Adjudicator
- Advertising Standards Authority (ASA)
- An Coimisinéir Teanga (Irish Language Commissioner)
- Citizens Advice
- Commissioner for Public Appointments
- Complaints Commissioner to the Bar Standards Board
- Dispute Resolution Services (IDRS)
- Dispute Service Ltd
- Furniture Ombudsman
- Immigration Services Commissioner
- Independent Case Examiner
- Independent Complaints Adjudicator for Ofsted and the Adult Learning Inspectorate
- Independent Complaints Mediator for the Criminal Records Bureau
- Independent Complaints Reviewer
- Independent Review Service
- Information Commissioner
- Institute Of Chartered Accountants Of Scotland
- Judicial Appointments & Conduct Ombudsman
- Law Society of Ireland
- Law Society of Scotland, Client Relations Office
- Lay Observer for Northern Ireland
- Legal Complaints Services
- Northern Ireland human Rights Commission
- Northern Ireland Judicial Appointments Ombudsman
- Office of Independent Adjudicator for Higher Education
- Older People's Commissioner for Wales
- Ombudsman for Children
- Press Ombudsman, Ireland
- Prisoner Ombudsman for Northern Ireland
- Prisons and Probation Ombudsman
- Regulation & Quality Improvement Authority
- Royal Institution of Chartered Surveyors, Professional Conduct Section
- Scottish Consumer Council
- Scottish Information Commissioner
- Scottish Legal Complaints Commission
- Scottish Parliamentary Standards Commissioner
- Scottish Prisons Complaints Commissioner
- Service Complaints Commissioner for the Armed Forces
- Standards Board for England
- States of Jersey Administrative Appeals System