| Ampetronic Solutions Limited | Newark | 2013 |
| Ampex Electricians 24/7 Ltd | Bolton | 2023 |
| Ampfab Limited | Oldham | 2009 |
| Amph Contracting Ltd | Taunton | 2025 |
| Amphastar UK Ltd | Bristol | 2016 |
| Amphenol Invotec Limited | Tamworth | 1986 |
| Amphenol Limited | Whitstable | 1963 |
| Amphenol Thermometrics (UK) Limited | Taunton | 1988 |
| Amphenol Trackwise Designs Limited | Whitstable | 2023 |
| Amphibia Base Ltd | Chester | 2016 |
| Amphibian Clothing Limited | Huntingdon | 2019 |
| Ampho Artisan Foods Limited | Guildford | 2020 |
| Amphora Technologies Limited | Lisburn | 2014 |
| Ampi Access Ltd | Kettering | 2025 |
| Ampigo Charge Ltd | Reading | 2024 |
| Ampiin Ltd | London | 2025 |
| Ample Cooling Limited | Hook | 2021 |
| Ample Infotech Ltd | London | 2025 |
| Ample Limited | Wolverhampton | 1996 |
| Ample Pharma Ltd | Luton | 2016 |
| Amplebox Limited | Leicester | 1990 |
| Amplicon Electronics Ltd | Brighton | 2020 |
| Amplifix Studios Ltd. | Gillingham | 2024 |
| Amplify Records 131 Limited | Bristol | 2013 |
| Amplify Records 1310 Limited | Bristol | 2013 |
| Amplify Records 132 Limited | Bristol | 2013 |
| Amplify Records 133 Limited | Bristol | 2013 |
| Amplify Records 134 Limited | Bristol | 2013 |
| Amplify Records 135 Limited | Bristol | 2013 |
| Amplify Records 136 Limited | Bristol | 2013 |
| Amplify Records 137 Limited | Bristol | 2013 |
| Amplify Records 138 Limited | Bristol | 2013 |
| Amplify Records 139 Limited | Bristol | 2013 |
| Amplify Records 141 Limited | Bristol | 2014 |
| Amplify Records 142 Limited | Bristol | 2014 |
| Amplify Records 143 Limited | Bristol | 2014 |
| Amplify Records 144 Limited | Bristol | 2014 |
| Amplify Records 145 Limited | Bristol | 2014 |
| Amplify Records 161 Limited | Bristol | 2016 |
| Amplify Records 162 Limited | Bristol | 2016 |
| Amplify Records 163 Limited | Bristol | 2016 |
| Amplify Records 164 Limited | Bristol | 2016 |
| Amplify Records 165 Limited | Bristol | 2016 |
| Amplimatic Distribution Limited | Leicester | 2025 |
| Amplimatic Engineering Limited | Leicester | 2023 |
| Ampliserve Limited | Shropshire | 2002 |
| Amplitude & Phase Technologies Co., Ltd | Cambridge | 2022 |
| Amplitude U.K. Limited | London | 2022 |
| Amplivox Limited | Birmingham | 1971 |
| Amplus Services Ltd | Milton Keynes | 2025 |
| Amplusmed Ltd | St. Neots | 2024 |
| Amplyfy Construct Ltd | Stockport | 2025 |
| Ampm Nutrition Ltd | Ammanford | 2024 |
| Ampnexus Ltd | Eastwood | 2021 |
| Ampode Limited | Altrincham | 2018 |
| Ampora Ltd | Dagenham | 2025 |
| Ampowr UK Ltd | Nether Alderley | 2022 |
| Amppower Engineering Ltd | Saltcoats | 2022 |
| Ampress Welding & Fabrications Limited | Lymington | 2004 |
| Amproelectrics Ltd | London | 2014 |
| Amps & Stephenson Limited | Halesworth | 2003 |
| Amps AM Ltd | Burnham-On-Crouch | 2025 |
| Amps Electrical Solutions Ltd | Kettering | 2023 |
| Ampsal Ltd | Birmingham | 2025 |
| Ampt Body Transformation Meals Ltd | Newry | 2018 |
| Ampteam Limited | Dudley | 1990 |
| Amptec Ltd | Sittingbourne | 2021 |
| Amptech Electrical Ltd | Sheffield | 2019 |
| Amptech Industrial Electrical Ltd | West Malling | 2023 |
| Amptex Electrical Ltd | Enfield | 2026 |
| Ampthill Electronic Manufacturing Services Limited | Ampthill | 2009 |
| Amptron Electrical Services Limited | Nottingham | 2006 |
| AMQ Bedrooms Limited | West Drayton | 2025 |
| AMR CUT & Make Textile Limited | Oldham | 2022 |
| AMR Facilities Maintenance Ltd | Doncaster | 2025 |
| AMR Magdy Shafik and HIS Partners Ltd | Manchester | 2026 |
| AMR P & P Ltd | Grimsby | 2013 |
| AMR Plant Maintenance and Repairs Ltd | Drybrook | 2025 |
| AMR Resin and Flame Ltd | Ashford | 2025 |
| AMR Service and Maintenance Ltd | Rotherham | 2018 |
| AMR Sheet Metal Fabrication Limited | Faringdon | 2003 |
| AMR Signs Ltd. | Horley | 2013 |
| AMR Telecom Limited | Brentford | 2016 |
| AMR Textiles Limited | Bolton | 2001 |
| Amrac Engineering Limited | Flax Bourton | 1996 |
| Amraf (Flixborough) Limited | London | 1962 |
| Amraf (North) Limited | London | 1931 |
| Amram Ltd | Barking | 2016 |
| Amrap Fitness Meals Ltd | Morecambe | 2019 |
| Amrit Foods Ltd | Reading | 2024 |
| Amritasoma Limited | London | 2023 |
| Amritha Enterprises Ltd | Mildenhall | 2024 |
| Amro Construction Limited | Manchester | 2017 |
| Amrock Onsite Mechanical Services Ltd | Ellesmere Port | 2012 |
| Amron Architectural Limited | Faversham | 2002 |
| Amrut (UK) Ltd | Harrow | 2003 |
| Amryis Limited | Beckenham | 2023 |
| AMS (Doonans) Ltd | Wimborne | 2023 |
| AMS (Hampshire) Limited | Godalming | 2015 |
| AMS (Stonemasons) Limited | Solihull | 2016 |