| Ablegrange Severn Heights Limited | Health & social care | 2004 |
| Ablequote Limited | Real estate | 1994 |
| Ablo Picasso London Ltd | Arts & recreation | 2024 |
| ABM Software Limited | Information & communication | 2009 |
| ABM Squad Limited | Other services | 2020 |
| ABM Squad Properties Ltd | Real estate | 2025 |
| ABN Associates Ltd | Professional & scientific | 2018 |
| Abode Hallam Ltd | Construction | 2014 |
| Above & Beyond TM Ltd | Construction | 2025 |
| Above and Beyond Builders Limited | Manufacturing | 2023 |
| Above Studio Limited | Professional & scientific | 2025 |
| Above the Stag Theatre Limited | Arts & recreation | 2023 |
| Above the Stars Limited | Real estate | 2010 |
| ABP Business Solutions Limited | Professional & scientific | 2014 |
| ABR Construction Services Limited | Construction | 2024 |
| ABR Group Limited | Real estate | 2016 |
| Abra Holdings Limited | Real estate | 2016 |
| Abridge Limited | Hospitality | 2009 |
| Abrion Ltd | Wholesale & retail | 2026 |
| ABS 2 Buy Limited | Wholesale & retail | 2022 |
| ABS Accountancy Services Ltd | Professional & scientific | 2025 |
| ABS Empowerment Limited | Health & social care | 2021 |
| ABS Medicon Limited | Real estate | 2014 |
| Absap Consulting Ltd | Information & communication | 2019 |
| Absolute Auto Traders Ltd | Wholesale & retail | 2026 |
| Absolute Carpentry Services Ltd | Manufacturing | 2021 |
| Absolute Data AI Limited | Information & communication | 2025 |
| Abstract Management Company Limited | Real estate | 2014 |
| Abstract Property Investments Ltd | Construction | 2020 |
| Abstractware Ltd | Education | 2021 |
| ABT Resourcing Limited | Construction | 2017 |
| Abtf Lighting Limited | Information & communication | 2026 |
| ABU Dhabi Arts Society | Education | 2020 |
| Abuncia Limited | Financial services | 2016 |
| Abvg Karma Limited | Real estate | 2016 |
| ABY Logistics Limited | Transport & logistics | 2025 |
| Aby&Florin Ltd | Administrative & support | 2025 |
| Abya Group Ltd | Information & communication | 2025 |
| Abyssusnet Limited | Professional & scientific | 2025 |
| ABZ Electric Ltd | Manufacturing | 2024 |
| ABZ Growth Specialists Ltd | Professional & scientific | 2026 |
| AC (Crawley) Ltd | Transport & logistics | 2012 |
| AC Business Continuity Limited | Professional & scientific | 2018 |
| AC Electrical Contracts (UK) Ltd | Construction | 2008 |
| AC Group Ltd | Extraterritorial | 2025 |
| AC Independent Ltd | Construction | 2022 |
| AC1 Construction Limited | Construction | 2010 |
| AC1 Consulting Ltd | Professional & scientific | 2018 |
| AC1 Developments Limited | Construction | 2018 |
| AC1 Holdings Limited | Real estate | 2025 |
| AC1 Maidenhead Project Limited | Construction | 2025 |
| AC1 Mancunian Limited | Real estate | 2024 |
| AC1 Victoria Limited | Construction | 2026 |
| Acacia Property Capital Limited | Financial services | 2018 |
| Acacia Tree Consultancy Limited | Health & social care | 2022 |
| ACADEMIA2LINK Ltd | Education | 2014 |
| Academics for Academic Freedom Limited | Other services | 2023 |
| Academy GT Ltd | Professional & scientific | 2014 |
| Academy of Tuition Ltd | Education | 2020 |
| Acanto Limited | Information & communication | 2007 |
| Acar Sailing Ltd | Administrative & support | 2023 |
| ACASA4U Limited | Real estate | 2024 |
| ACC Group 1 Ltd | Construction | 2026 |
| ACC Mechanical Ltd | Construction | 2019 |
| Accademia Dell'Opera Italiana Ltd | Education | 2022 |
| Accario Limited | Administrative & support | 2015 |
| Accelerate Technology Solutions Ltd | Professional & scientific | 2023 |
| Accent Construc Ltd | Construction | 2020 |
| Access Car and Commercials Ltd | Wholesale & retail | 2021 |
| Access Commercials (UK) Limited | Wholesale & retail | 2008 |
| Access Contractors UK Ltd | Construction | 2017 |
| Access Group London Ltd | Financial services | 2023 |
| Access Publishing Ltd | Professional & scientific | 2025 |
| Access Rigging Services Limited | Manufacturing | 2023 |
| Access Transport London Ltd | Transport & logistics | 2023 |
| Accident Courtesy Limited | Administrative & support | 2006 |
| Acclaim Business Services Ltd | Professional & scientific | 2011 |
| Accomax Limited | Hospitality | 1982 |
| Accon Services Ltd | Professional & scientific | 2015 |
| Accord Accountants Ltd | Professional & scientific | 2009 |
| Accord Clinical Support Limited | Professional & scientific | 2010 |
| Account-Ability (UK) Ltd | Professional & scientific | 2010 |
| Accountants 4 Life Limited | Professional & scientific | 2021 |
| Accounting Aspects Limited | Professional & scientific | 2010 |
| Accountomate Limited | Information & communication | 2022 |
| Accountscompiler Limited | Extraterritorial | 2015 |
| Accprof Limited | Professional & scientific | 2004 |
| Accrete Group Ltd | Hospitality | 2024 |
| Accrington Trading Ltd | Wholesale & retail | 2017 |
| Acculedger Ltd | Professional & scientific | 2025 |
| Accusmart Ltd | Professional & scientific | 2022 |
| Accutrust Ltd | Professional & scientific | 2023 |
| Ace & Thrive (Holdings) Ltd | Other services | 2023 |
| Ace (Chelsea) Limited | Real estate | 2015 |
| Ace Builders & Decorators Ltd | Construction | 2025 |
| Ace Cars Rentals Ltd | Administrative & support | 2025 |
| Ace Competence Ltd | Professional & scientific | 2014 |
| Ace Consultants Ltd | Information & communication | 2011 |
| Ace Dog Care Ltd | Other services | 2022 |
| Ace Drivewise Limited | Education | 2022 |