| Algo Vehicle Solutions Ltd | Wholesale & retail | 2021 |
| Alialb Ltd | Wholesale & retail | 2025 |
| Alice & Sons Ltd | Health & social care | 2021 |
| Alideck Limited | Manufacturing | 2019 |
| Aliev Construction Limited | Construction | 2025 |
| Aljydeprojects Limited | Construction | 2010 |
| ALL Aspect Contractors Ltd | Construction | 2021 |
| ALL Care Builders Limited | Construction | 2018 |
| ALL Flourish Cosmetics Ltd | Administrative & support | 2017 |
| ALL in Mind Care Services Ltd | Health & social care | 2014 |
| ALL in One Electrical Contractors Limited | Construction | 2020 |
| ALL Kent Cooling Limited | Construction | 2020 |
| ALL Manuals & Videos Ltd | Information & communication | 2005 |
| ALL Manuals Ltd | Administrative & support | 2024 |
| ALL Paving Solutions Ltd | Construction | 2018 |
| ALL Pink Ltd | Hospitality | 2025 |
| ALL Pulley & Gear Developments Limited | Manufacturing | 1999 |
| ALL Pulley & Gear Holdings Ltd | Professional & scientific | 2021 |
| ALL Saints Gardens Residents Company Limited | Households | 2002 |
| ALL Site Installations Limited | Construction | 2023 |
| ALL Size Builds Ltd | Construction | 2024 |
| ALL Task Provider Ltd | Administrative & support | 2023 |
| ALL the Best Publishing Limited | Arts & recreation | 2016 |
| ALL Things Pink Ltd | Other services | 2025 |
| Allbits Plumbing and Heating Supplies Limited | Wholesale & retail | 1999 |
| Allcare Facilities Management Limited | Construction | 1997 |
| Allcerts London Ltd | Construction | 2014 |
| Alleast Security Ltd | Administrative & support | 2023 |
| ALLEN3IN1UK Ltd | Construction | 2014 |
| Allergy Focus Ltd | Education | 2026 |
| Allhallows Caravan Park Ltd | Other services | 2019 |
| Alliance Fire Safety Limited | Other services | 2010 |
| Allium Properties (Kent) Limited | Real estate | 2017 |
| Allout Properties Ltd | Real estate | 2022 |
| Allpoints Painters and Decorators Ltd | Construction | 2011 |
| Allpsu Limited | Wholesale & retail | 2001 |
| Allroofs-Uk Ltd | Construction | 2021 |
| Allstar Electrical (Kent) Ltd | Construction | 2023 |
| Alltask Holdings Limited | Financial services | 2014 |
| Alltask Human Resources Limited | Administrative & support | 2014 |
| Alltask Industrial & Environmental Services Limited | Construction | 2014 |
| Alltask Scaffolding Limited | Construction | 2014 |
| Allthingstogether UK Limited | Administrative & support | 2015 |
| ALM Legacy Limited | Real estate | 2019 |
| Alma IT Sales Recruitment Limited | Administrative & support | 2013 |
| Almost Midnight Ltd | Wholesale & retail | 2025 |
| Alph Pharm Ltd | Health & social care | 2024 |
| Alpha Builders Ltd | Construction | 2024 |
| Alpha Crownes Publishing Limited | Information & communication | 2017 |
| Alpha Fire Systems Limited | Construction | 2006 |
| Alpha Innovations Ltd | Construction | 2026 |
| Alpine Power Tools Limited | Administrative & support | 1988 |
| ALT Trading Post Ltd | Wholesale & retail | 2021 |
| Altair Living Ltd | Wholesale & retail | 2018 |
| Alteryn Ltd | Information & communication | 2026 |
| Altocapa Limited | Information & communication | 2020 |
| Altura Drone Surveys Ltd | Professional & scientific | 2025 |
| Aluna Wellness Ltd | Arts & recreation | 2025 |
| Alvearia Ltd | Health & social care | 2025 |
| AM Assemble Limited | Information & communication | 2017 |
| AM Electrical Services ( Kent ) Limited | Other services | 2014 |
| AM Machine Tools Ltd | Professional & scientific | 2022 |
| Am&Pm Limited | Extraterritorial | 2014 |
| AMA Media Services Ltd | Construction | 2024 |
| AMA Portfolio Limited | Real estate | 2025 |
| AMA Tasty Food Ltd | Manufacturing | 2024 |
| Aman's Hair & Beauty Ltd | Other services | 2019 |
| Amanda Gordon (UK) Ltd. | Other services | 2009 |
| Amaranth Sustainable Development LLP | | 2013 |
| Amazing Grace Bakery Ltd | Hospitality | 2019 |
| Amazing Space Properties Ltd | Real estate | 2023 |
| Amazing Space UK Limited | Other services | 2007 |
| AMB Rail & Utility Ltd | Professional & scientific | 2014 |
| Ambedo Communications Ltd | Professional & scientific | 2023 |
| Ambertrace Labs Ltd | Information & communication | 2024 |
| Ambri Eyewear Ltd | Wholesale & retail | 2025 |
| Ambulance Medic Limited | Transport & logistics | 2023 |
| Ameerah Health Limited | Health & social care | 2010 |
| Amend Advertising Ltd | Professional & scientific | 2022 |
| Ameron Service Ltd | Administrative & support | 2016 |
| AMG Filtration Limited | Other services | 2021 |
| Amiga Scaffolding Ltd | Construction | 2019 |
| Amkp Medical Services Ltd | Health & social care | 2025 |
| Amma Assets Limited | Real estate | 2020 |
| Amma Children's Homes Limited | Health & social care | 2026 |
| Amma Digital Limited | Information & communication | 2018 |
| Amma Healthcare & Support Agency Ltd | Health & social care | 2025 |
| Ammara Medical Company Limited | Health & social care | 2021 |
| Amore & Pasta Ltd | Hospitality | 2023 |
| Amore Facilities Management Limited | Manufacturing | 2024 |
| Amorsjay Solutions Ltd | Other services | 2023 |
| Amped Electrical Solutions Ltd | Administrative & support | 2017 |
| Amplify Investments Ltd | Financial services | 2014 |
| Ampofo Solutions Ltd | Information & communication | 2024 |
| Amps Markets Ltd | Construction | 2024 |
| Amrit Estates Ltd | Real estate | 2022 |
| AMS Services South East Ltd | Construction | 2025 |
| Amsco Logistics Limited | Transport & logistics | 1999 |
| Amtb Limited | Information & communication | 2016 |
| Amxg Ltd | Transport & logistics | 2024 |