| Alan D Hairdressing Limited | Other services | 2008 |
| Alan Mathers Plant Limited | Professional & scientific | 2015 |
| Alan Mitchell Electrical Ltd | Construction | 2018 |
| Aland Cumbria Ltd | Education | 2021 |
| Alans Builging Limited | Construction | 2025 |
| Alarabi Apartments Ltd | Households | 2022 |
| Alawaba Management Limited | Professional & scientific | 2005 |
| Albanian Info Ltd | Information & communication | 2018 |
| Albans Close Residence RTM Company Limited | Households | 2009 |
| Albany Court Residents Association (Egham) Limited | Households | 2007 |
| Albany Mews (Cheltenham) Limited | Households | 1992 |
| Albany Mews (Sutton) Management Company Limited | Households | 1993 |
| Albany Walk Management (Plots 102 to 116) Limited | Households | 1991 |
| Albany Walk Management (Plots 15-29) Limited | Households | 1991 |
| Albany Walk Management (Plots 83-97) Limited | Households | 1991 |
| Albatal Ltd | Information & communication | 2025 |
| Albefine Limited | Wholesale & retail | 2025 |
| Albert Hall Mansions (Block 4) Freehold Limited | Households | 2010 |
| Albert Mews (Clapham) Management Limited | Households | 1999 |
| Albert Street Management (Fleet) Limited | Households | 1985 |
| Albert Walk Management Limited | Households | 1993 |
| Alberta's Care Limited | Health & social care | 2024 |
| Alberto Barcha Junior Limited | Health & social care | 2024 |
| Albion Court (Dunstable) Management Company Limited | Households | 1972 |
| Albion House Farringdon Exchange Management Limited | Households | 1998 |
| Albion Towerfields Property Management Company Limited | Households | 2003 |
| Albone Properties Ltd | Real estate | 2016 |
| Albrofarming Limited | Manufacturing | 2025 |
| Albrofarms Ltd | Manufacturing | 2025 |
| Albuna Solutions Ltd | Information & communication | 2013 |
| Albury Road (Guildford) Management Company | Households | 2004 |
| Alby School of Motoring Ltd. | Education | 2011 |
| ALC Solutions Ltd | Professional & scientific | 2025 |
| Alcam Resourcing Ltd | Administrative & support | 2020 |
| Alcestis Saguan Corporation Limited | Health & social care | 2013 |
| Alchemy Media Services Ltd | Professional & scientific | 2023 |
| Aldek Ltd | Wholesale & retail | 2022 |
| Alders HSE Consult Ltd | Professional & scientific | 2023 |
| Aldhelm Court Management Company Limited | Households | 2017 |
| Aleel Management Limited | Extraterritorial | 2020 |
| Aleena Jamil Limited | Professional & scientific | 2019 |
| Aleesharich Limited | Wholesale & retail | 2020 |
| Alejandra London Aesthetics Limited | Other services | 2015 |
| Alekcsm Ltd | Professional & scientific | 2015 |
| Aleksa's Beauty Ltd | Other services | 2015 |
| Alert K9 Security Ltd | Administrative & support | 2021 |
| Alex Blomeley Ltd | Information & communication | 2018 |
| Alex Builders (London) Limited | Construction | 2021 |
| Alex Canova Ltd | Construction | 2025 |
| Alex Davis (UK) Ltd | Professional & scientific | 2025 |
| Alex Fixing Ltd | Construction | 2016 |
| Alex Joinery Limited | Construction | 2011 |
| Alex Renovations & Landscaping Ltd | Construction | 2026 |
| Alex Zepherin Ltd | Professional & scientific | 2019 |
| Alexander & Bjorck Holdings Ltd | Financial services | 2024 |
| Alexander & Bjorck Limited | Hospitality | 2015 |
| Alexander George Frederick Smith Ltd | Professional & scientific | 2024 |
| Alexander James Property Management Limited | Real estate | 2024 |
| Alexandra Cleaners Ltd | Administrative & support | 2025 |
| Alexandra Court (Crosby) Management Company Limited | Households | 2005 |
| Alexandra Davis Limited | Professional & scientific | 2017 |
| Alexandra Expert Cleaners Ltd | Administrative & support | 2024 |
| Alexandra Lanark Limited | Households | 1991 |
| Alexandra Road (Aldershot) Management Company Limited | Households | 2006 |
| Alexandre Motorcycles Accessories Ltd | Wholesale & retail | 2024 |
| Alexandre Motorcycles Ltd | Wholesale & retail | 2018 |
| Alexandre Motorcycles M.O.T. Center Ltd | Wholesale & retail | 2021 |
| Alexandre Motorcycles Rent Ltd | Administrative & support | 2024 |
| Alexis and Jade Properties Limited | Real estate | 2025 |
| Alfa Consultancy Services Ltd | Information & communication | 2022 |
| Alfa-Zero Limited | Hospitality | 2018 |
| Alffie Contracts Limited | Administrative & support | 2025 |
| Algo-Chain Ltd | Information & communication | 2021 |
| Alhaso Management (UK) Limited | Financial services | 2015 |
| ALI & Sons Limited | Real estate | 2004 |
| ALI 23 Ltd | Real estate | 2023 |
| ALI 4 Sons Ltd | Real estate | 2019 |
| ALI Hospitality Rental Business Ltd | Hospitality | 2026 |
| ALI Properties Kent Ltd | Real estate | 2022 |
| Alianthus Private Limited | Wholesale & retail | 2025 |
| Alice Gate Management Company Limited | Households | 2008 |
| Alicel Company Service Ltd | Extraterritorial | 2025 |
| Alien Mind Ltd | Information & communication | 2022 |
| Alif Coaching Limited | Professional & scientific | 2023 |
| Aliglass Ltd | Construction | 2020 |
| Align Atelier Limited | Wholesale & retail | 2025 |
| Alimmar Limited | Wholesale & retail | 2026 |
| Alina Massage and Healing Limited | Health & social care | 2023 |
| Alis Accountants Limited | Professional & scientific | 2019 |
| Alis Halal Ltd | Wholesale & retail | 2023 |
| Aliumm Systems Ltd | Information & communication | 2013 |
| ALJ Consulting Services Limited | Professional & scientific | 2023 |
| ALJ Health Limited | Administrative & support | 2023 |
| ALJ LDN Ltd | Professional & scientific | 2018 |
| Aljo Properties Ltd | Real estate | 2020 |
| Alkan Real Estates Ltd | Real estate | 2020 |
| Alkitglow Services Ltd | Administrative & support | 2025 |
| Alkom Limited | Professional & scientific | 2015 |
| ALL Avenues Explored Ltd | Hospitality | 2011 |
| ALL Cars 1 Porchester Limited | Wholesale & retail | 2023 |