| Association of British Investigators Limited(The) | Borehamwood | 1970 |
| Association of British Neurologists | London | 1999 |
| Association of British Orchestras(The) | Covent Garden | 1984 |
| Association of British Pewter Craftsmen Limited | London | 1970 |
| Association of British Professional Conference Organisers(The) | Thrapston | 1987 |
| Association of British Riding Schools | Horsham | 1996 |
| Association of British Tamil Lawyers Limited | Northolt | 2021 |
| Association of British Turkish Professionals CIC | London | 2022 |
| Association of British Veterinary Acupuncturists | Northwich | 2007 |
| Association of British-Azerbaijani Doctors and Dentists CIC | Birmingham | 2025 |
| Association of Brokers & Yacht Agents Limited(The) | Petersfield | 1985 |
| Association of Business Poets Ltd | Horsham | 2025 |
| Association of Business Recovery Professionals | London | 1990 |
| Association of Catering Excellence Ltd | Kingston Upon Thames | 2005 |
| Association of Certified Management Accountants | Bolton | 2005 |
| Association of Certified Non-Executive Directors | Loughborough | 2025 |
| Association of Certified Professional Accountants | Southport, | 2011 |
| Association of Certified Professionals | Waltham Cross | 2018 |
| Association of Chairs | London | 2012 |
| Association of Charitable Foundations | London | 2004 |
| Association of Chief Executives of Voluntary Organisations | London | 1998 |
| Association of Child Abuse Lawyers | Ashtead | 1999 |
| Association of Child Psychotherapists Ltd | London | 2015 |
| Association of Chinese Collectors UK | London | 2014 |
| Association of Chinese Medicine Practitioners | London | 2004 |
| Association of Chinese Tourism, UK | | 2006 |
| Association of Christian Writers | Attleborough | 1998 |
| Association of Church Accountants and Treasurers Corporate Trustee Limited | Burnley | 2016 |
| Association of Circus Proprietors GB Limited | London | 2021 |
| Association of Classic Trials Clubs Limited | Ilminster | 2001 |
| Association of Clinical Pathologists(The) | Hove | 1956 |
| Association of Clinical Psychologists U.K. C.I.C. | Clacton-On-Sea | 2018 |
| Association of Colleges | London | 1996 |
| Association of Commercial P & I Insurers Limited | London | 2021 |
| Association of Community Amateur Sports Clubs & Community Interest Fundraisers (Acasc/Acif) CIC | Bristol | 2009 |
| Association of Community Organizations for Reform NOW International Ltd | Bristol | 2026 |
| Association of Company Registration Agents Limited(The) | Stockport | 1975 |
| Association of Concerned Nigerians UK Ltd | Edgware | 2019 |
| Association of Conference Executives Limited | St. Ives | 1971 |
| Association of Conservative Clubs Limited(The) | London | 1948 |
| Association of Construction Attorneys | Bridge Of Weir | 2008 |
| Association of Consultant Architects Limited(The) | Basildon | 1978 |
| Association of Consulting Actuaries Limited | Wokingham | 2016 |
| Association of Consumer Support Organisations Ltd | Lancaster | 2019 |
| Association of Contact Lens Manufacturers Limited(The) | Swindon | 1962 |
| Association of Convenience Stores Limited | Farnborough | 2000 |
| Association of Core Process Psychotherapists | Wellington | 2017 |
| Association of Crime and Intelligence Analysts (Acia) | Bristol | 2008 |
| Association of Croatian British Professionals CIC | London | 2025 |
| Association of Dance Freestyle Professionals Limited | Walsall | 2025 |
| Association of Democratic Services Officers | London | 2009 |
| Association of Descendants of General Yang Hucheng's 38TH Army Overseas | Sidcup | 2023 |
| Association of Dog Boarders | Reading | 2019 |
| Association of Electricity Producers Limited | London | 1993 |
| Association of Electricity Supply Pensioners Limited | Lincoln | 1996 |
| Association of Energy Engineers (UK) Limited | Ware | 2022 |
| Association of Equality Scheme Providers | Kington | 2012 |
| Association of Event Venues Limited | Hertfordshire | 2004 |
| Association of Ex-Round Tablers' Clubs Limited | Birmingham | 2025 |
| Association of Facilitators | Reading | 2011 |
| Association of Fencing Industries | Peterborough | 2016 |
| Association of First Aiders | London | 2013 |
| Association of Foreign Banks | London | 1991 |
| Association of Fundraising Consultants and Freelancers | Grantham | 1992 |
| Association of Geotechnical and Geoenvironmental Specialists | Faversham | 1991 |
| Association of Ghanaian Ex-Servicemen & Women UK Ltd | Stanmore | 2004 |
| Association of Grace Baptist Churches (East Anglia) Limited | London | 1930 |
| Association of Health and Wellbeing Coaches CIC | Bury St. Edmunds | 2025 |
| Association of Illustrators Limited(The) | Ingatestone | 1975 |
| Association of Immigrants | Crawley | 2009 |
| Association of Independent Celebrants Ltd | Barton-Upon-Humber | 2019 |
| Association of Independent Creative Education | Huddersfield | 1997 |
| Association of Independent Inventory Clerks Limited | London | 2023 |
| Association of Independent Meat Suppliers | Harrogate | 2002 |
| Association of Independent Movers | Twickenham | 2013 |
| Association of Independent Risk & Fraud Advisors | Harrow | 2013 |
| Association of Indoor Play Ltd | Brentford | 2020 |
| Association of Interior Specialists Limited | Solihull | 2015 |
| Association of International Accountants(The) | Newcastle Upon Tyne | 1932 |
| Association of International Certified Public Accountants | Newcastle Upon Tyne | 2004 |
| Association of International Courier & Express Services | Hounslow | 1982 |
| Association of International Economic Strategy | London | 2022 |
| Association of International Financial Accountants | Newcastle Upon Tyne | 2007 |
| Association of International Lawyers CIC | London | 2022 |
| Association of Interpreters and Translators | London | 2019 |
| Association of Italian Chefs in U.K. Limited | West Wickham | 2021 |
| Association of Italian Scientists in the UK (Aisuk) | London | 2015 |
| Association of Lawyer Fifa Football Agents Ltd | Glasgow | 2025 |
| Association of Local Environmental Records Centres CIC | York | 2009 |
| Association of Lymphoedema Practitioners | Waterlooville | 2026 |
| Association of Manufacturers of Power Generating Systems (Amps) | Peterborough | 1989 |
| Association of Maritime Professionals Limited | Rochester | 2021 |
| Association of Massage and Manipulative Therapists Limited | Colne | 2011 |
| Association of Mbas and Business Graduates Association | London | 1967 |
| Association of Medical Research Charities | London | 1987 |
| Association of Mental Health First Aiders | London | 2023 |
| Association of Microchip Database Operators | Coleford | 2023 |
| Association of Model Agents Limited(The) | London | 1974 |
| Association of Mongolian Women in the UK Limited | Wembley | 2025 |
| Association of Mountaineering Instructors | Conwy | 2012 |