| Amei Group Limited | Hospitality | 2025 |
| Ameisa Ltd | Wholesale & retail | 2021 |
| Amelia Quigley Dance Company Ltd | Education | 2026 |
| Amelia's Properties 4U Ltd | Real estate | 2014 |
| Amelja Ltd | Wholesale & retail | 2021 |
| Amell 1 Limited | Wholesale & retail | 2025 |
| American Sweets Preston Ltd | Wholesale & retail | 2025 |
| Amethyst Assessment Centre Limited | Health & social care | 2022 |
| Amethyst Financial Planning Limited | Financial services | 2002 |
| Amethyst Wealth Solutions Ltd | Extraterritorial | 2012 |
| AMG Bookkeeping Services Ltd | Professional & scientific | 2014 |
| AMG Industrial Solution Ltd | Households | 2024 |
| AMI Fire Protection Ltd | Construction | 2002 |
| Amielok & Company Ltd | Health & social care | 2015 |
| Amiet Bros Flooring Ltd | Construction | 2020 |
| Amigos Properties Limited | Real estate | 2026 |
| Amijis Candy’S Ltd | Manufacturing | 2026 |
| Amina's Wonder Spice UK (PVT) Ltd | Wholesale & retail | 2014 |
| Amirou Holdings Limited | Wholesale & retail | 2018 |
| Amisa Co. Ltd | Health & social care | 2009 |
| Amit Patel Parcels Ltd | Transport & logistics | 2025 |
| AMJ Richardson Holdings Ltd | Professional & scientific | 2023 |
| AMK Pharma Ltd | Wholesale & retail | 2021 |
| AMK Properties Preston Ltd | Real estate | 2023 |
| Amkmlv LLP | | 2023 |
| AML Lancs Limited | Hospitality | 2025 |
| Amla.Dark Kitchen Ltd | Hospitality | 2025 |
| Amma Illam Ltd | Real estate | 2025 |
| Ammo North West Ltd | Wholesale & retail | 2018 |
| Amms North West Limited | Real estate | 2026 |
| Ammu & Chinnu Ltd | Real estate | 2024 |
| Ammu Ltd | Health & social care | 2018 |
| AMN Properties England Ltd | Real estate | 2021 |
| Amns North West Limited | Real estate | 2017 |
| AMO Consulting Ltd | Professional & scientific | 2021 |
| Amodaia Limited | Other services | 2011 |
| Amol Chitre Limited | Health & social care | 2023 |
| Amore Event Stylists Limited | Other services | 2023 |
| Amore Luxury Lettings Ltd | Hospitality | 2024 |
| Amore Supplies Ltd | Wholesale & retail | 2024 |
| Amorino Limited | Wholesale & retail | 2026 |
| AMP and Sons Limited | Real estate | 2025 |
| AMP Drainage Solutions Ltd | Water & waste | 2026 |
| AMP Information Systems Ltd | Information & communication | 1999 |
| Ampersand Medical Communications Limited | Professional & scientific | 2017 |
| Amplify Training and Coaching Ltd | Education | 2014 |
| Amplio Solutions Ltd | Information & communication | 2022 |
| Ampsahead Ltd | Information & communication | 2023 |
| AMR Electrical Contractors (NW) Ltd | Other services | 2015 |
| AMR Energy Group Ltd | Other services | 2015 |
| AMR Group Ltd | Hospitality | 2021 |
| AMR Sales and Lettings Ltd | Real estate | 2024 |
| Amrev Co Limited | Wholesale & retail | 2025 |
| Amritha Associates Limited | Health & social care | 2014 |
| AMS Cladding Limited | Construction | 2001 |
| AMS Legacy Ltd | Real estate | 2025 |
| AMS Private Ltd | Transport & logistics | 2023 |
| AMS Solicitors Limited | Professional & scientific | 2006 |
| AMS Structures Ltd | Extraterritorial | 2020 |
| Amsa Estates Limited | Administrative & support | 2008 |
| Amsa Limited | Real estate | 1999 |
| Amste Limited | Wholesale & retail | 2023 |
| Amston Electrical Ltd | Construction | 2023 |
| Amtrim Ltd | Manufacturing | 2015 |
| AMY Burnett Ales Ltd | Hospitality | 2024 |
| AMY Business Search Ltd | Professional & scientific | 2023 |
| AMY Hackett-Jones Ltd | Professional & scientific | 2024 |
| AMY Nicholas Limited | Professional & scientific | 2005 |
| AMY Spencer Entertainments Limited | Professional & scientific | 2020 |
| AMY Spencer Limited | Professional & scientific | 2022 |
| AMY Victoria Designs Ltd | Professional & scientific | 2017 |
| Amzn Ltd | Health & social care | 2024 |
| AN Empowered Life Ltd | Information & communication | 2009 |
| AN Livings Ltd | Real estate | 2025 |
| AN News Ltd | Wholesale & retail | 2025 |
| ANA UM Ltd | Health & social care | 2020 |
| Anadea Shop Limited | Wholesale & retail | 2023 |
| Analogue Pictures Ltd | Information & communication | 2023 |
| Analytix 360 Ltd | Information & communication | 2024 |
| Anaori Limited | Wholesale & retail | 2026 |
| Anapamu Limited | Professional & scientific | 2011 |
| Anas Car Valet Ltd | Administrative & support | 2025 |
| Anas Private Ltd | Transport & logistics | 2025 |
| ANB Northern Trans Ltd | Transport & logistics | 2022 |
| ANC Shipping Line Limited | Transport & logistics | 2016 |
| Anchor Direct Ltd | Wholesale & retail | 2026 |
| Anchor Social Care Limited | Health & social care | 2025 |
| Anchorage Business Parks Ltd | Real estate | 2004 |
| Anchorage Quay Management Company Limited | Households | 1997 |
| Ancoats Coffee Limited | Wholesale & retail | 2013 |
| Ancube Couriers Ltd | Transport & logistics | 2025 |
| AND Business Solutions Ltd | Professional & scientific | 2024 |
| AND Commercials Ltd | Construction | 2024 |
| AND Property Lettings Ltd | Real estate | 2023 |
| Ander Audio Ltd | Information & communication | 2025 |
| Anderton Consultancy Ltd | Transport & logistics | 2011 |
| Anderton Gables Limited | Professional & scientific | 2007 |
| Andrea Dobson Ltd | Professional & scientific | 2010 |
| Andrea Edwards Aesthetics Lounge Ltd | Health & social care | 2022 |
| Andrena Backhouse Ltd | Financial services | 1988 |