| Allied Engines Ltd | Wholesale & retail | 2020 |
| Almila Barber Ltd | Other services | 2024 |
| Almondbox Ltd | Real estate | 2014 |
| Alncompany Ltd | Wholesale & retail | 2025 |
| Alottville Ltd | Health & social care | 2024 |
| Alpha Capital Finance Ltd | Financial services | 2010 |
| Alpha DEZ Ltd | Construction | 2026 |
| Alpha K9 Protection Ltd | Administrative & support | 2024 |
| Alpha Rigging Ltd | Arts & recreation | 2017 |
| Alpha Sealant Ltd | Construction | 2020 |
| Alpha Solutions Ltd | Construction | 2014 |
| Alpha Tools Ltd | Wholesale & retail | 2018 |
| Alpha Trek Transport Limited | Transport & logistics | 2022 |
| Alpha-Dawn Limited | Health & social care | 2015 |
| Alphabadge Ltd | Real estate | 2025 |
| Alphareg Limited | Administrative & support | 2020 |
| Alpharo Limited | Real estate | 2023 |
| Alpine Lift Services Ltd | Professional & scientific | 2020 |
| Altaira Properties Ltd | Real estate | 2024 |
| Altoo Limited | Health & social care | 2015 |
| Aluminium Bi-Folds.Org Limited | Construction | 2013 |
| Alvanley Residential Park Limited | Real estate | 2015 |
| Alvin Construction Ltd | Construction | 2024 |
| ALX Construct Ltd | Construction | 2026 |
| Alzoni Ltd | Administrative & support | 2020 |
| AM & GE Transport Limited | Transport & logistics | 2026 |
| AM Cards Limited | Wholesale & retail | 2010 |
| AM Fire Safety & Testing Ltd | Professional & scientific | 2022 |
| AM Gambit Joinery Limited | Construction | 2017 |
| AM Investment Limited | Real estate | 2018 |
| AMA Recruitment Limited | Administrative & support | 2025 |
| AMA Support Care Services Ltd | Administrative & support | 2019 |
| AMA Transport Limited | Transport & logistics | 2016 |
| Amaanah Attire Limited | Wholesale & retail | 2023 |
| Amaca Investments Ltd | Real estate | 2019 |
| Aman Roofing Services Ltd | Construction | 2016 |
| Amanah London Ltd | Wholesale & retail | 2025 |
| Amanha Consulting Limited | Information & communication | 2011 |
| Amar 1TRANSPORT Ltd | Transport & logistics | 2026 |
| Amareta Cafe Limited | Hospitality | 2025 |
| Amas Contractors Ltd | Construction | 2023 |
| Amav Ltd | Construction | 2024 |
| Amaysa Ltd | Real estate | 2025 |
| Amazing Gardeners Ltd | Administrative & support | 2019 |
| Amazonlearn Childcare Ltd | Education | 2022 |
| Ambar Care Ltd | Health & social care | 2016 |
| Ambassadors Foundation Limited | Other services | 2009 |
| Amber Elite Solutions Limited | Construction | 2024 |
| Amberberry Services Limited | Real estate | 2017 |
| Ambrose Garment Company Limited | Wholesale & retail | 2014 |
| Ambrose Property Consultancy Limited | Professional & scientific | 2011 |
| Ambrose Tech Limited | Construction | 2018 |
| Ambulance Transfers Limited | Transport & logistics | 2015 |
| AMD Tuning Essex Limited | Wholesale & retail | 2023 |
| Amell Property Solutions Limited | Real estate | 2024 |
| Amersy Holdings Ltd | Real estate | 2026 |
| Amid Installation Ltd | Construction | 2023 |
| AMK Drylining Ltd | Construction | 2026 |
| AMK1 Limited | Construction | 2025 |
| AMM General Limited | Transport & logistics | 2019 |
| Ammaya Investments Limited | Transport & logistics | 2018 |
| Ammofam Invest Ltd | Transport & logistics | 2019 |
| Amnov Limited | Health & social care | 2023 |
| Ampa Solutions Limited | Information & communication | 2026 |
| AMPHIBIA23 Ltd | Transport & logistics | 2022 |
| AMR Property Management Limited | Real estate | 2016 |
| Amra Academy Limited | Education | 2018 |
| Amran Pittman Medical Ltd. | Health & social care | 2023 |
| Amrowe Limited | Administrative & support | 2012 |
| AMS Construction Services Ltd | Construction | 2025 |
| Amwell Homes Limited | Construction | 2017 |
| AMY Media International Ltd | Information & communication | 2015 |
| ANA Consult Limited | Professional & scientific | 2025 |
| ANA Immigration Advisers Limited | Professional & scientific | 2025 |
| Anamaniacs Investments Limited | Real estate | 2016 |
| Anax (Services) Limited | Construction | 2013 |
| Anchor Financial Ltd | Professional & scientific | 2026 |
| Anchor House Investments Limited | Information & communication | 2017 |
| AND Retail UK Ltd | Wholesale & retail | 2024 |
| Andbog Ltd | Wholesale & retail | 2017 |
| Andena's Driving Solutions Ltd | Administrative & support | 2016 |
| Anderson Corps Limited | Households | 2025 |
| Andi TZ Logistics Ltd | Transport & logistics | 2021 |
| Andor Logistics Solutions Ltd | Transport & logistics | 2025 |
| Andra's Transport Ltd | Transport & logistics | 2026 |
| Andrei HGV Trans Ltd | Transport & logistics | 2016 |
| Andrei T87 Limited | Transport & logistics | 2017 |
| Andrelaw Ltd | Transport & logistics | 2025 |
| Andrew Tuck Mortgage Advice Ltd | Financial services | 2015 |
| Andreyas Recruitment Ltd | Administrative & support | 2025 |
| Andrius Constructions Limited | Construction | 2020 |
| Andromo Ltd | Information & communication | 2018 |
| Andru RN Limited | Transport & logistics | 2015 |
| Andy Collier Personal Training Ltd | Arts & recreation | 2019 |
| Anemac Marquees & Event Hire Limited | Administrative & support | 2011 |
| Anera Estates Ltd | Real estate | 2026 |
| Aneta Jakubas Photography Ltd | Information & communication | 2023 |
| ANG Groundworks Limited | Construction | 2016 |
| Anganeyen Property Limited | Real estate | 2025 |
| Angel Cafe (Chafford Hundred) CIC | Hospitality | 2012 |