| A.R Kurd Logistics Ltd | Transport & logistics | 2026 |
| A.S Translations Limited | Professional & scientific | 2019 |
| A.V.A. Building & Construction Limited | Construction | 2007 |
| A1 Drylining & Plastering Ltd | Construction | 2014 |
| A1 Guildford Ltd | Real estate | 2025 |
| A1 Ipswich Ltd | Real estate | 2025 |
| A1 Kingston Ltd | Real estate | 2023 |
| A1 Lincoln Ltd | Real estate | 2024 |
| A1 Maidstone Ltd | Real estate | 2026 |
| A1 Manpower Services Limited | Administrative & support | 2019 |
| A2 Baker Street Ltd | Real estate | 2022 |
| A2 Bexleyheath Ltd | Real estate | 2022 |
| A2 Electrics and Heating Ltd | Construction | 2024 |
| A2 Guildford Ltd | Hospitality | 2025 |
| A2 Hadley Ltd | Real estate | 2023 |
| A2 Hanley Limited | Real estate | 2021 |
| A2 Harrow Ltd | Hospitality | 2025 |
| A2 Ilford Ltd | Real estate | 2021 |
| A2 Ipswich Ltd | Hospitality | 2025 |
| A2 Kettering Ltd | Real estate | 2021 |
| A2 Kilburn Ltd | Real estate | 2022 |
| A2 Kingston Ltd | Real estate | 2024 |
| A2 Maidstone Ltd | Hospitality | 2026 |
| A2 Putney Ltd | Real estate | 2021 |
| A2 Romford Ltd | Real estate | 2018 |
| A2 Southend Ltd | Hospitality | 2025 |
| A2 Stevenage Ltd | Hospitality | 2021 |
| A2 Walthamstow Ltd | Real estate | 2022 |
| A2B GAS Services Ltd | Energy | 2020 |
| A2S Limited | Real estate | 2005 |
| A2Z Transport & Services Ltd | Transport & logistics | 2024 |
| A3 Stevenage Limited | Other services | 2011 |
| A4MY Investment Ltd | Real estate | 2020 |
| AA Cleaners Limited | Administrative & support | 2019 |
| AA Greenfields Exports Ltd | Wholesale & retail | 2019 |
| AA Interiors Limited | Construction | 2012 |
| AA Rigging Ltd | Information & communication | 2017 |
| Aabrs Limited | Other services | 2011 |
| Aada Ltd | Administrative & support | 2017 |
| Aadhira Realty Ltd | Real estate | 2019 |
| AAH Capital Holdings Limited | Financial services | 2025 |
| AAH Developments Ltd. | Construction | 2016 |
| AAL Borehamwood Ltd | Wholesale & retail | 2024 |
| Aali Limited | Health & social care | 2025 |
| Aamabuwa Limited | Health & social care | 2011 |
| Aamaya Limited | Other services | 2020 |
| Aameds Pharma Limited | Financial services | 2025 |
| Aandrbrickwork Ltd | Construction | 2012 |
| Aariya Property Limited | Real estate | 2021 |
| Aark Life Solutions Ltd | Real estate | 2021 |
| Aaron, Chadha and Evans Ltd. | Professional & scientific | 1993 |
| AB FAS 1 Holdco Limited | Real estate | 2021 |
| AB LIN Civils Ltd | Construction | 2021 |
| AB Psychoanalytic Ltd | Health & social care | 2023 |
| AB Theatre Production Limited | Information & communication | 2016 |
| ABA Cars Ltd | Transport & logistics | 2009 |
| Abacus Pools & Spas Ltd | Administrative & support | 2015 |
| Abbas Dhalla Ltd | Health & social care | 2012 |
| Abbeville Capital Ltd | Financial services | 2026 |
| Abbotsbury Properties Limited | Real estate | 1985 |
| Abby & Gabby Ltd | Wholesale & retail | 2019 |
| ABC (Blakeney) Limited | Real estate | 2026 |
| ABC Residential Services Limited | Real estate | 2012 |
| Abcostume Ltd | Arts & recreation | 2023 |
| ABD Medical Services Limited | Health & social care | 2015 |
| Abdullah Medical Consultant Ltd | Health & social care | 2024 |
| Abelflow Ltd | Construction | 2024 |
| Aberdare Lettings Ltd | Real estate | 2022 |
| Abhi Consulting Services Limited | Information & communication | 2012 |
| Abhiash Limited | Information & communication | 2019 |
| Abit Solutions Limited | Information & communication | 2007 |
| Able Fisher Limited | Administrative & support | 2012 |
| Able-X Limited | Professional & scientific | 2025 |
| Abmax Partners Ltd | Real estate | 2023 |
| Abod Consultancy Limited | Information & communication | 2017 |
| Above ALL Rigging Limited | Information & communication | 2010 |
| ABS Airconditioning Limited | Extraterritorial | 2008 |
| ABS Lawyers Limited | Professional & scientific | 2016 |
| Absolute Swales Limited | Arts & recreation | 2016 |
| Abstract Post Ltd | Information & communication | 2023 |
| ABT Woodwork Ltd | Construction | 2024 |
| AC7 Limited | Construction | 2020 |
| Academic Powerhouse (UK) Limited | Professional & scientific | 2009 |
| Academy of Logi-Care Intervention Ltd | Transport & logistics | 2011 |
| Acap Support Services UK Ltd | Administrative & support | 2025 |
| Accelogy Ltd | Information & communication | 2026 |
| Access ALL Brands Merchandise Ltd | Wholesale & retail | 2015 |
| Accord Holdings Limited | Professional & scientific | 1999 |
| Accord Search Limited | Professional & scientific | 2000 |
| Accountancy Action Limited | Administrative & support | 2001 |
| Accountancy in UK Ltd | Professional & scientific | 2023 |
| Accountancy Resources Limited | Administrative & support | 2018 |
| Accountant 4 YOU Ltd | Professional & scientific | 2024 |
| Accounts Tax and VAT Limited | Financial services | 2006 |
| Accura Accountants Business Recovery Turnaround Limited | Professional & scientific | 2015 |
| Accura Accountants Limited | Professional & scientific | 2011 |
| Accura Accountants SME Limited | Professional & scientific | 2019 |
| Accura Audit Limited | Professional & scientific | 2023 |
| Accura Limited | Professional & scientific | 2019 |
| Accuratepay Solutions Ltd | Extraterritorial | 2022 |