| Amiz Autos Ltd | Middlesbrough | 2025 |
| AMJ Tech International Co., Ltd | Kington | 2015 |
| Amjad Trading Co., Ltd | London | 2021 |
| Amjoa Group Ltd | Northampton | 2025 |
| AMK Aquaculture Limited | Cookstown | 2014 |
| Amkn Formidling Limited | London | 2023 |
| Amko Investments Ltd | Didcot | 2014 |
| AML Cars Limited | Holmfirth | 2010 |
| AML Finance Group Ltd | Plymouth | 2021 |
| AML Overseas Services Limited | Gaydon | 2008 |
| AML Technologies Limited | Woodstock | 2007 |
| AMM Bookkeeping & Accountancy Ltd | Cheltenham | 2024 |
| AMM Electrical Ltd | Highbridge | 2024 |
| AMM Farming Ltd. | London | 2014 |
| AMM Innovations Ltd | Stafford | 2022 |
| AMM Locums Limited | Henley On Thames | 2014 |
| Ammaazing Ltd | London | 2018 |
| Amman Valley Welders Limited | Ammanford | 2011 |
| Ammazin Limited | Tetbury | 2014 |
| Ammo (Advance Media & Marketing Opportunities) Limited | London | 1994 |
| Ammonite (ST Neots) Limited | London | 2013 |
| Ammonite (ST Neots) Nominees Limited | London | 2013 |
| Amna Ventures Ltd | London | 2024 |
| Amnek Limited | Twickenham | 2011 |
| AMO Automotive Ltd | Buckingham | 2022 |
| Amoeba Gifts Ltd | London | 2011 |
| Amoil Supplies Limited | Warrington | 1997 |
| Amon Amarth UK Limited | Holborn | 2020 |
| Among Giants Limited | | 1997 |
| Amor Sailing Ltd | London | 2024 |
| Amore Adira Limited | Bayswater | 2025 |
| Amore Cleveleys Limited | Thornton-Cleveleys | 2020 |
| Amore Paws Ltd | Shipley | 2020 |
| Amore Stationery Ltd | Birmingham | 2022 |
| Amorfitness Ltd | Chatham | 2024 |
| Amoria Group Ltd | Ipswich | 2025 |
| Amorlife Coaching & Consultancy Limited | London | 2023 |
| Amoto Wheels | Stafford | 2020 |
| AMP Automotive Ltd | Southampton | 2024 |
| AMP Investment Management Ltd | Gosport | 2013 |
| Ampac Holding Ltd | Kenilworth | 1999 |
| Ampacc Ltd | New Malden | 2022 |
| Ampaeus Ltd | Huddersfield | 2013 |
| Ampco 113 Limited | Alfreton | 2015 |
| Amper Fashion International Limited | Beckenham | 2008 |
| Amperevolt Ltd | West Bromwich | 2020 |
| Amphibious Design Ltd | Montrose | 2024 |
| Ample Imports Limited | Belper | 2000 |
| Amplify HER Ltd | London | 2023 |
| Amplify Wealth Limited | London | 2022 |
| Amplio Global Ltd | London | 2020 |
| Amplio Holdings Ltd | Somerton | 2015 |
| Amports Cargo Services Limited | London | 1989 |
| Amports Contract Personnel Limited | London | 1989 |
| Amports Holdings Limited | London | 1995 |
| Amports Vehicle Terminals Limited | London | 1991 |
| Ampthill Grange Ltd | Harpenden | 2011 |
| Ampthill Property Limited | London | 2018 |
| AMR Pipelines Limited | Cheshire | 1994 |
| AMR1T Limited | Wigan | 2010 |
| Amra Limited | London | 1987 |
| Amrap Fitness Ltd | London | 2021 |
| Amrimia Limited | Southampton | 2002 |
| Amrisons Limited | Leicester | 2012 |
| Amrit Sons (UK) Limited | Maidenhead | 2003 |
| Amrita Nutrition Limited | Sheffield | 2021 |
| Amritsari Kulcha Ltd | Slough | 2019 |
| Amritsari Tandoori Kulcha Ltd | Slough | 2019 |
| Amron Special Projects Limited | Faversham | 2021 |
| Amrovan Limited | Birmingham | 2017 |
| Amrut Herbal Care Limited | London | 2008 |
| Amrutarupa Limited | Milton Keynes | 2017 |
| Amrw Investments Limited | Birmingham | 2024 |
| AMS Consulting Services Ltd | Bexley | 2022 |
| AMS Environmental Ltd | St Werburghs | 2000 |
| AMS EOT Limited | Exeter | 2021 |
| AMS Global Safety Ltd | Aberdeen | 2020 |
| AMS Industries Limited | Polegate | 2013 |
| AMS Maintenance Cumbria Ltd | Wigton | 2024 |
| AMS Norway Limited | London | 2022 |
| AMS Plumbers Merchants Limited | Stockton Heath | 1993 |
| AMS Plumbing Supplies Holdings Limited | Newbury | 2018 |
| AMS Plumbing Supplies Limited | Newbury | 1998 |
| AMS Rentals Ltd | Buckingham | 2025 |
| AMS RES Ltd | London | 2025 |
| AMS Shell Limited | | 1994 |
| AMS Staffs Ltd | Newcastle | 2024 |
| AMS Structures Ltd | Preston | 2020 |
| AMS Technology Park Management Company Ltd | Newbury Park | 2017 |
| Amsene Ltd | Thetford | 2023 |
| Amshiver Enterprises Ltd | London | 2024 |
| Amsik Property Limited | Pinner | 1999 |
| Amso Limited | Manchester | 2012 |
| Amsord Limited | Cardiff | 2016 |
| Amsterlain Limited | Leeds | 1957 |
| AMT Investments (2011) Limited | Greenford | 2011 |
| AMT Marine Ltd | London | 2024 |
| AMT Property Holdings Ltd | Bootle | 2023 |
| Amtast Co., Ltd | Beckenham | 2019 |
| Amtrak Express Parcels (UK) Limited | Gravesend | 2008 |