| Amariz Limited | Bristol | 1999 |
| Amarok OIL Ltd | London | 2022 |
| Amaroni Limited | Boston | 2019 |
| Amarsat Ltd | Loughborough | 2019 |
| Amarthpal Holdings Limited | London | 2025 |
| Amaruz Holding Limited | London | 2026 |
| Amaryllis Capital Limited | Bristol | 2025 |
| Amaryllis Corp Limited | London | 2016 |
| Amas Capital Investments Ltd | Slough | 2023 |
| Amas Developments Ltd | Slough | 2025 |
| Amass Holdings Ltd | Keston | 2021 |
| Amass Trading Limited | Maidstone | 2012 |
| Amaste Ltd | London | 2019 |
| Amaste Ownership Ltd | Redhill | 2024 |
| Amasus Short-Sea Ltd | Newton Abbot | 2013 |
| Amaterasu Holding Limited | London | 2024 |
| Amateur British Gymnastics Investments Limited | Newport | 2019 |
| Amathus Capital Ltd. | London | 2020 |
| Amathus Drinks Group Ltd | London | 2024 |
| Amathus Holdings Limited | London | 2025 |
| Amati Global Investors Limited | Edinburgh | 1999 |
| Amato Capital Limited | London | 2023 |
| Amato Holdings Ltd | Manchester | 2024 |
| Amatola Holdings Ltd | Strathaven | 2017 |
| Amatrite Ltd | London | 2018 |
| Amatzia B.G.D. Limited | London | 2025 |
| Amava Holding Ltd | Sunderland | 2025 |
| Amavi Mortgages Ltd | London | 2023 |
| Amax Holdings London Ltd | Harrow | 2021 |
| Amaxe Holdings Limited | Nr Falmouth | 2023 |
| Amaya NR Limited | Rochdale | 2018 |
| Amaya SM Ltd | Bournemouth | 2022 |
| Amaya Ventures Limited | Devizes | 2019 |
| Amayi Capital Ltd | Polegate | 2021 |
| Amayra Limited | London | 2014 |
| Amaze Group Ltd | Doncaster | 2026 |
| Amazing LEO Ltd | Leicester | 2025 |
| Amazing Mortgage Solutions Limited | Stanmore | 2024 |
| Amazing Prop Trader Limited | Solihull | 2024 |
| Amazon Capital Ltd | Wells | 2012 |
| Amazon Group Limited | Padstow | 2021 |
| Amazon Holdings Limited | Padstow | 2019 |
| Amazonica Group Ltd | Ipswich | 2025 |
| Amazza Limited | Wigan | 2024 |
| AMB Advisory Limited | London | 2016 |
| AMB Bereavement Organisation Ltd | Birmingham | 2022 |
| AMB Broker Ltd | St Neots | 2017 |
| AMB Chester Ltd | Chester | 2014 |
| AMB Financial Ltd | Peterborough | 2017 |
| AMB Financial Solutions Ltd | Oxted | 2025 |
| AMB Group Holdings Ltd | Ashford | 2023 |
| AMB Insurance Services Ltd. | Newcastle Under Lyme | 2003 |
| AMB Mortgage Solutions Ltd | Derby | 2011 |
| AMB Newco 03 Limited | London | 2013 |
| AMB Rural & Commercial Ltd | Tiverton | 2025 |
| AMB Securities Limited | Worcester | 2013 |
| AMB1 Holdings Ltd | London | 2024 |
| Amba Dockside Holdings Limited | Waterlooville | 2013 |
| Amba Hydraulics Holdings Limited | Stanford-Le-Hope | 2023 |
| Ambac Assurance UK Limited | London | 1996 |
| Ambacpdp Holding Ltd | Morden | 2026 |
| Ambam Investments Limited | Leiceser | 2015 |
| Ambank Asset Management Ltd | London | 2025 |
| Ambar Group Limited | Corby | 2018 |
| Ambassadeurs Group Limited | London | 2021 |
| Ambassador (UK) Limited | London | 2006 |
| Ambassador Aspen Group Limited | London | 2021 |
| Ambassador Capital Partners 1 Limited | London | 2020 |
| Ambassador Financial Services Limited | Milton Keynes | 2013 |
| Ambassador Holdings Ltd. | Reading | 1986 |
| Ambassador Services Group Limited | Dartford | 2024 |
| Ambassador Textiles Holdings Ltd | Huddersfield | 2025 |
| Ambatoja Limited | London | 2026 |
| Ambec Group Ltd | Stafford | 2023 |
| Ambehr Limited | London | 2026 |
| Ambelena Ltd | Wirral | 2013 |
| Ambell Ltd | Colchester | 2024 |
| Ambella Designs Ltd | Dolgellau | 2024 |
| Amber (Balsall Common) Holdings Limited | London | 2017 |
| Amber 3SIIF Investments Limited | London | 2021 |
| Amber AL Holdings Limited | London | 2017 |
| Amber April Limited | Godalming | 2026 |
| Amber Arrow Holding Company Limited | Armagh | 2021 |
| Amber Bridging Limited | London | 2021 |
| Amber Business Group Ltd | Sutton | 2023 |
| Amber Capital and Holdings Ltd | London | 2026 |
| Amber Capital Group Ltd | London | 2024 |
| Amber Capital UK Holdings Limited | London | 2006 |
| Amber Compounds Holdings Limited | High Peak | 2022 |
| Amber Development Partners GP Limited | London | 2021 |
| Amber Development Partners Investco Limited | London | 2021 |
| Amber Digital GP Ltd | London | 2017 |
| Amber Digital Investments Limited | London | 2017 |
| Amber Energy Land Holdings Limited | London | 2016 |
| Amber Energy Storage Limited | London | 2017 |
| Amber Energy Storage Three Crown Limited | London | 2018 |
| Amber Energy Storage Two Limited | London | 2017 |
| Amber Enterprise Group Limited | Hoddesdon | 2022 |
| Amber FIC Limited | Manchester | 2025 |
| Amber Finance (Bains) Ltd | Wolverhampton | 2013 |