| A. G. Barr Plc | Bolton |
| A1GP World Cup of Motorsport | London |
| ABB Ltd | Warrington |
| Abbey | Milton Keynes |
| Abbott Laboratories Ltd | Queenborough |
| Aberdeen Asset Management Plc | London |
| ABN AMRO Asset Management | London |
| Absolute Radio | London |
| Absolute Radio | London |
| Accenture | London |
| Acergy M.S. Ltd | London |
| ACP-Natmag | London |
|
Action Against Hunger UK | London |
| Action for Employment | Sheffield |
| Active Sports Marketing Ltd | Wilmslow |
| ACU - Auto-Cycle Union Ltd | Rugby |
|
Addaction | London |
| Adecco | Borehamwood |
| Adidas UK Ltd | Stockport |
| AdLINK Internet Media Ltd | London |
| ADMICAL (Assoc pour le Développement du Mécénat Industriel et Commercial) | 75018 Paris |
| Admiral Insurance Services Ltd | Cardiff |
| Adnams PLC | Southwold |
| ADT Fire & Security Plc | Sunbury on Thames |
| The Advertising Association (AA) | London |
| Advice UK | London |
| AEDME (Spanish Association for the Development of Business Sponsorship) | 08006 Barcelona |
| AEG Sponsorship | London |
| Aegon UK PLC | Edinburgh |
| Aga Foodservice Group plc | Solihull |
| Aggregate Industries UK Ltd | Markfield |
| AIG UK Ltd | London |
| Air Products plc | Walton-on-Thames |
| The Aircraft Owners' & Pilots' Association (AOPA) | London |
| The AirMiles Travel Company | Warrington |
| AKS (Arbeitskreis Kultursponsoring) | Berlin |
| Alan Ransome Sporting Goods | Middlesbrough |
| Alfred Dunhill Ltd | London |
| Alitalia Italian Airlines | Hounslow |
| The All England Lawn Tennis & Croquet Club | London |
| Allen & Overy LLP | London |
| Alliance & Leicester PLC | Leicester |
| Allianz Plc | Guildford |
| Allied Bakeries | Maidenhead |
| Alpha Accommodation Ltd | Sheffield |
| The Amateur Boxing Association of England (ABA) | Sheffield |
| Amateur Motor Cycle Association (AMCA) | Cannock |
| Amateur Rowing Association (ARA) | London |
| Amateur Swimming Association (ASA) | Loughborough |
| Amer Sports UK | Frimley |
| American Airlines | Hounslow |
| American Express Services Europe Ltd | London |
| Anglian Group Plc | Norwich |
| Anglo-American plc | London |
| Anglo-Irish Bank | London |
| Anheuser-Busch InBev Europe Ltd | Richmond |
| Anheuser-Busch InBev UK Ltd | Luton |
| Anschutz Entertainment Group | London |
| AOL UK Ltd | London |
| Aon Ltd | London |
| Apex Tubulars Ltd | Aberdeen |
| Aquaid Franchising Ltd | Cambridge |
| Aquascutum Ltd | London |
| Ardi Kolah | London |
| Argent Group Plc | London |
| Argyll Insurance Group | Worthing |
| ArkSports | London |
| Arla Foods UK Plc | Leeds |
| Arriva plc | Sunderland |
| Artemis Fund Managers | Edinburgh |
| Artful Sponsorship & Fundraising | Edinburgh |
|
Arthritis Research Campaign (arc) | Chesterfield |
| Arts & Business | London |
| Arts & Business (East) | Cambridge |
| Arts & Business (East Midlands) | Nottingham |
| Arts & Business (North West) | Manchester |
| Arts & Business (Northern) | Newcastle upon Tyne |
| Arts & Business (Northern Ireland) | Belfast |
| Arts & Business (Scotland) | Edinburgh |
| Arts & Business (South East) | Brighton |
| Arts & Business (South West) | Bristol |
| Arts & Business (Yorkshire) | Halifax |
| Arts & Business (Midlands) | Birmingham |
| Arts Council England | London |
| Arts Council England, East | Cambridge |
| Arts Council England, East Midlands | Nottingham |
| Arts Council England, London | London |
| Arts Council England, North East | Newcastle upon Tyne |
| Arts Council England, North West | Manchester |
| Arts Council England, South East | Brighton |
| Arts Council England, South West | Exeter |
| Arts Council England, West Midlands | Birmingham |
| Arts Council England, Yorkshire | Dewsbury |
| The Arts Council of Northern Ireland | Belfast |
| The Arts Council of Wales (Mid & West Wales) | Carmarthen |
| The Arts Council of Wales (North Wales) | Colwyn Bay |
| The Arts Council of Wales | Cardiff |
| The Arts Foundation | London |
| Ascot Park Polo Club | Woking |
| ASDA Stores Ltd | Leeds |
| ASICS UK | Warrington |
| Ask.com | London |
| Associated British Ports (Holdings Ltd) | London |
| Associated Newspapers Ltd | London |
| Associated Northcliff Digital | London |
| Association of Arts Fundraisers (AAF) | Cheltenham |
| Association of British Riding Schools (ABRS) | Penzance |
| Association of Charitable Foundations (ACF) | London |
| The Association for Physical Education | Reading |
| Association of Independent Museums (AIM) | Midhurst |
| Association Libanaise pour le Développement du Mécénat Culturel | 166334 Beirut |
| The Association of Fundraising Consultants | London |
| Aston Manor Brewery Company Ltd | Birmingham |
|
Aston Villa Football Club | Birmingham |
| AstraZeneca PLC | London |
| AT & T (UK) Ltd | Redditch |
| Athole Still International Ltd | London |
| Atos Origin | London |
| attheraces | London |
| Audi UK | Milton Keynes |
| The Australia Business Arts Foundation | Melbourne |
| Aviva Plc | London |
| Avon Cosmetics Ltd | Northampton |
| AXA Art | London |
| AXA UK Plc | London |
| Axis Europe plc | London |
| Azorie Consulting Ltd | London |
| Azzurri Communications Ltd | Walsall |
