| A-M.Yoga Ltd | Edgware | 2008 |
| A-Ok Live Limited | Twickenham | 2023 |
| A-R-K-H-I-V-E X Ltd | Canterbury | 2022 |
| A-S Land Services Limited | Methlick | 2024 |
| A-Side Consultancy Limited | London | 2005 |
| A-Sports Management Ltd | Middlesbrough | 2023 |
| A-Team Ltd | Maldon | 2025 |
| A-Train Productions Limited | Cobham | 2011 |
| A-Wave.Com Ltd | London | 1999 |
| A-Ya Design Ltd | Newcastle | 2016 |
| A-Z Sports Coaching Ltd | London | 2016 |
| A. Andrews Limited | Loughton | 2019 |
| A. B. Gray Limited | Rotherham | 2019 |
| A. Bradley Amusements Limited | Bolton | 2026 |
| A. Copping Technical Systems (Communications) Limited | 37/41 Prince Street | 1991 |
| A. D. Gittins Ltd | Bristol | 2004 |
| A. F. C. Fylde Limited | Preston | 2006 |
| A. J. Mannings Extreme Body Challenge Limited | Birmingham | 2019 |
| A. J. S. Invision Limited | Sutton | 2013 |
| A. K. K. Studios Ltd | London | 2013 |
| A. L. L. Manners Ltd | Market Harborough | 2023 |
| A. Links & Company, Limited | Glasgow | 1938 |
| A. Pennyworth Ltd | Bristol | 2023 |
| A. Quinn Limited | London | 2003 |
| A. R. D. Leisure Limited | Sunderland | 2013 |
| A. Scheffler Limited | | 2005 |
| A. Smith Enterprises Limited | London | 1982 |
| A. Smith Holdings Limited | London | 1998 |
| A. Smith Management Limited | London | 1998 |
| A. T. Nail Limited | Brighton | 2003 |
| A. W. Parkview Limited | Stafford | 2023 |
| A.& G.(Amusements)Limited | Scarborough | 1939 |
| A.A. Baines (Racing) Limited | Ashford | 1975 |
| A.B Production Services Ltd | London | 2024 |
| A.B.Eurospania Ltd | Manchester | 2019 |
| A.C. Coaching Limited | Oldham | 2003 |
| A.C. Motorsport Ltd | Cardiff | 2024 |
| A.C.E Football Academy Ltd | Ashford | 2026 |
| A.C.E. Target Sports Ltd | Portree | 2026 |
| A.C.Sheehan Ltd | London | 2010 |
| A.C.T.S Music Lessons Ltd | Warminster | 2022 |
| A.C.T.S Theatre Arts School Ltd | Upton Scudamore | 2017 |
| A.D Pilates Limited | South Croydon | 2025 |
| A.D. Health & Fitness Ltd | Shifnal | 2024 |
| A.D. Keys Music Ltd | Nottinghamshire, Nottingham | 2024 |
| A.D. Productions Limited | London | 1981 |
| A.E. Hopcraft Limited | Richmond | 1986 |
| A.G. Wilson (Promotions) Limited | Boston | 1967 |
| A.G.E. Compressor Services Limited | Prescot | 1983 |
| A.G.S. Sailing Limited | Poole | 2004 |
| A.H Movie Sculpture Ltd | Sunderland | 2023 |
| A.H.S. (Mechanical) Limited | Leicester | 2000 |
| A.I.M. Academy of Dance Limited | Shillington | 2016 |
| A.J. Alexander Ltd | Brentwood | 2019 |
| A.J. Event Services Ltd | London | 2016 |
| A.J. Fitness Limited | Business Park Great Blakenham | 2000 |
| A.J. Wilson Communications Ltd | Congleton | 2022 |
| A.J.G. Leisure Ltd | Sheffield | 2009 |
| A.J.W. Motorcycles Limited | Milton Keynes | 2003 |
| A.K Fitness Ltd. | Whitley Bay | 2015 |
| A.K Kumar Limited | Bicester | 2021 |
| A.K.Ashhh Ltd | Coventry | 2023 |
| A.K.E Sports Management Limited | London | 2018 |
| A.L.E.R.T. Activities Limited | Swansea | 1999 |
| A.L.Scarlett Ceramics Ltd | Lymington | 2024 |
| A.Lorraine Wall Art & Portraits Ltd | Aylesbury | 2026 |
| A.M. Sessions Ltd | St. Neots | 2015 |
| A.Ma Leisure Limited | Maidstone | 2017 |
| A.O.H. Limited | London | 2018 |
| A.P-E Training Systems Ltd | Glasgow | 2022 |
| A.P. Metalcraft Limited | Birmingham | 1938 |
| A.P. Publications Limited | Luton | 2006 |
| A.P.Productions Entertainment & Events Limited | Aylesbury | 2007 |
| A.R. Gill & Co. Limited | London | 2011 |
| A.S. Basic Limited | London | 2014 |
| A.S.O. U.K. Limited | London | 1999 |
| A.S.P.I. Helping Hands CIC | Birmingham | 2025 |
| A.S.P.I.R.E Sports Management Services Limited | Basildon | 2024 |
| A.W. Costumes Limited | Whiteley Bank | 2008 |
| A.W.Entertainments Ltd | Brentwood | 2022 |
| A.W.O.L Music Limited | London | 2009 |
| A/C 4 Services Limited | Exeter | 1997 |
| A1 Agency Limited | Hope Valley | 1998 |
| A1 Agility Equipment Ltd | Arlesey | 2026 |
| A1 Alliance Limited | Dunmow | 2022 |
| A1 Amusement Services Limited | Dundee | 2015 |
| A1 Bouncy Castle Ltd | Princes Risborough | 2021 |
| A1 Competitions Limited | Aberdeen | 2026 |
| A1 Discos Limited | Reading | 1998 |
| A1 Entertainment Ltd | Wembley | 2022 |
| A1 Events Management Limited | Leeds | 2003 |
| A1 Fitness London Ltd | London | 2015 |
| A1 Football Coaching Ltd | Erith | 2020 |
| A1 Grand Prix Productions Limited | London | 2005 |
| A1 Infinite Performance Limited | Newcastle Upon Tyne | 2018 |
| A1 Judo Club Limited | Ilford | 2025 |
| A1 Jump & Bounce Limited | Ebbw Vale | 2018 |
| A1 Management Limited | Arkley | 2016 |
| A1 Padel Ltd | Colsterworth | 2025 |
| A1 Performance Studio Ltd | Wigan | 2021 |