| Angstrom GAS and Electric Limited | Construction | 2016 |
| Angus and Sons Trading Limited | Wholesale & retail | 2025 |
| Anhydrous Car Wash Services Ltd | Other services | 2019 |
| ANI Power Limited | Energy | 2016 |
| Anicres UK Ltd | Wholesale & retail | 2014 |
| Anidis Ltd | Administrative & support | 2015 |
| Anilove Catering Service Limited | Arts & recreation | 2011 |
| Anima Youth C.I.C. | Education | 2019 |
| Animals at Home (Croydon) Ltd | Other services | 2011 |
| Anisha Restaurant Limited | Hospitality | 2025 |
| Anisro Investments Ltd | Real estate | 2018 |
| Anita Skinner Fostering Limited | Administrative & support | 2025 |
| Anitrendy Ltd | Wholesale & retail | 2025 |
| Anjaneya Homes Ltd | Real estate | 2023 |
| Anjeni Cosmetics Ltd | Wholesale & retail | 2025 |
| Anjeni Enterprises Ltd | Real estate | 2024 |
| Ankara Avenue Ltd | Wholesale & retail | 2025 |
| Ankara Hair Acadamy Ltd | Other services | 2023 |
| Ankers & Harbour Limited | Wholesale & retail | 2025 |
| Anlaby Court (Cheltenham) Management Limited | Households | 1980 |
| ANM Estates LLP | | 2024 |
| Anmer Management Company Limited | Households | 2015 |
| ANN House RTM Company Limited | Households | 2025 |
| ANN Mwesigwa Ltd | Health & social care | 2026 |
| Ann's Store Limited | Wholesale & retail | 2025 |
| Anna Lena Limited | Health & social care | 2014 |
| Anna's Events (London) Limited | Hospitality | 2025 |
| Anna's London Limited | Hospitality | 2022 |
| Anna-Maria Coscoros Interior Design Limited | Professional & scientific | 2016 |
| Annabels Diamonds Limited | Manufacturing | 2025 |
| Annahl Limited | Hospitality | 2019 |
| Annamselva Properties Ltd | Real estate | 2025 |
| Annapurna Enterprises Ltd | Health & social care | 2016 |
| Annascroydon Ltd | Hospitality | 2022 |
| Anne Cuthbert Solicitors Ltd | Professional & scientific | 2017 |
| Annenke Solutions Ltd | Other services | 2017 |
| Annette (UK) Services Limited | Health & social care | 2015 |
| Anney Services Limited Limited | Health & social care | 2023 |
| Annique Care Limited | Health & social care | 2013 |
| Annivents Limited | Other services | 2017 |
| Annodco Services Limited | Professional & scientific | 2017 |
| Anny's Limited | Manufacturing | 2015 |
| Annys Express Limited | Hospitality | 2022 |
| Annys Flavours Limited | Hospitality | 2020 |
| Annys Takeaway Ltd | Hospitality | 2024 |
| Anodising & Platings Ltd | Manufacturing | 1945 |
| ANP Assets Ltd | Real estate | 2023 |
| Ansacare Fostering Agency Ltd | Health & social care | 2009 |
| Ansaf Properties Limited | Real estate | 2021 |
| Anssaniax Ltd | Wholesale & retail | 2026 |
| Anstey News & OFF License Ltd | Wholesale & retail | 2018 |
| Anstey Place (Leicester Road) Management Company Limited | Households | 2005 |
| ANT Imports & Exports Limited | Wholesale & retail | 2021 |
| ANT Logistics (London) Ltd. | Transport & logistics | 2012 |
| Antalya Aviation Limited | Professional & scientific | 2025 |
| Ante Keep Ltd | Real estate | 2023 |
| Anthony Adesanmi Ltd. | Health & social care | 2017 |
| Anthony Bravo Consulting Ltd | Education | 2026 |
| Anthony Pobee Limited | Construction | 2014 |
| Anthony Solomon Limited | Real estate | 2018 |
| Anthony White Ltd | Administrative & support | 2016 |
| Anthos Consulting Ltd | Professional & scientific | 2020 |
| Anti-Trafficking Ltd | Professional & scientific | 2026 |
| Antiks Enterprise Ltd | Wholesale & retail | 2025 |
| Antillia Homes Limited | Wholesale & retail | 2018 |
| Antlia Court RTM Company Limited | Households | 2024 |
| Antoinette Alexis Ltd | Administrative & support | 2021 |
| Anton John Investments Ltd | Real estate | 2013 |
| Anton Laurence Couture Limited | Manufacturing | 2008 |
| Antonella Beauty Ltd | Other services | 2016 |
| Antoni Construction Limited | Construction | 2019 |
| Antonia Bronze Couture Ltd | Manufacturing | 2024 |
| Antonia Bronze Ltd | Wholesale & retail | 2018 |
| Antonio Delicatessen Ltd | Hospitality | 2014 |
| Antss Ltd | Administrative & support | 2025 |
| Anura Ventures Limited | Professional & scientific | 2019 |
| Anvira London Limited | Wholesale & retail | 2025 |
| Anvox Ltd | Construction | 2026 |
| Anwar ALI Consultants Limited | Professional & scientific | 2014 |
| ANY Car Hire Limited | Administrative & support | 2016 |
| ANY Day NOW Ltd | Professional & scientific | 2019 |
| Anyigold Global Services Limited | Wholesale & retail | 2025 |
| Anyrx Limited | Administrative & support | 2014 |
| Anything for Less Ltd | Wholesale & retail | 2025 |
| Anythingcango Limited | Wholesale & retail | 2024 |
| Anza Limited | Real estate | 2026 |
| Anzo London Limited | Wholesale & retail | 2021 |
| AO Carpentry Solutions Limited | Construction | 2017 |
| AOA Marine Limited | Transport & logistics | 2023 |
| AP & NP Property Limited | Real estate | 2022 |
| AP ALB Construction Ltd | Construction | 2023 |
| AP Chaudhry Limited | Health & social care | 2023 |
| AP Consulting Services Limited | Education | 2024 |
| AP Fresh Fish and Meat Ltd | Wholesale & retail | 2024 |
| AP Motors Ealing Limited | Manufacturing | 2025 |
| AP1 Limited | Real estate | 2021 |
| Apac (Elmers END) Properties Ltd | Real estate | 2023 |
| Apbs OIL and GAS Ltd | Professional & scientific | 2013 |
| Apcars and Couriers Limited | Wholesale & retail | 2014 |
| Apci-Uk | Other services | 2013 |