| Auris Tech Limited | Information & communication | 2015 |
| Aurum Hair Ltd | Health & social care | 2014 |
| Austia Limited | Mining & quarrying | 2017 |
| Austinco Services Limited | Information & communication | 2017 |
| Austyns Place Management Company Limited | Households | 2003 |
| Authentic Spanish Boots Ltd | Wholesale & retail | 2019 |
| Autism 121 Services LLP | | 2018 |
| Autism Ace Services Limited | Administrative & support | 2021 |
| Auto Trade Center Ltd | Wholesale & retail | 2023 |
| Automatron Ltd | Wholesale & retail | 2021 |
| Autosales (N.I.) Limited | Wholesale & retail | 2023 |
| Autotest (West Ewell) Ltd | Wholesale & retail | 2010 |
| Autumn Gold Ltd | Manufacturing | 2023 |
| Auty Precision Products Limited | Manufacturing | 1984 |
| AV Specialist Limited | Information & communication | 2017 |
| Avaans Consulting Ltd | Administrative & support | 2021 |
| Avaia Beauty Ltd | Other services | 2025 |
| Avance Developments Ltd | Real estate | 2020 |
| Avanta Intermare Holdings Ltd | Professional & scientific | 2020 |
| Avantio Limited | Professional & scientific | 2019 |
| Avayo Global Ltd | Manufacturing | 2025 |
| Avenue Homes Estate Agents Ltd | Professional & scientific | 2020 |
| Averley Developments Ltd | Real estate | 2018 |
| Aviary Investment Holdings Limited | Financial services | 1973 |
| Aviation Press Limited | Professional & scientific | 2011 |
| Avida Property Group Ltd | Real estate | 2025 |
| Avramov UK Limited | Construction | 2019 |
| AVV Plastic Ltd | Manufacturing | 2018 |
| AVW Window Cleaning Ltd | Administrative & support | 2013 |
| AW Corporation Limited | Professional & scientific | 2016 |
| Awal Limited | Professional & scientific | 2019 |
| AWB Group Limited | Financial services | 2006 |
| AWB Print Limited | Manufacturing | 2008 |
| AWE Europe Limited | Wholesale & retail | 1935 |
| Awesome Awesomness Limited | Households | 2020 |
| Awesome Source Games Limited | Extraterritorial | 2025 |
| AWM Technical Services Limited | Professional & scientific | 2015 |
| AWR South East Limited | Construction | 2024 |
| Awrc Limited | Professional & scientific | 2014 |
| Axiomatic Advisory Services Ltd | Professional & scientific | 2024 |
| Axis Digital Solution Ltd | Information & communication | 2026 |
| Ayaana Care Ltd | Health & social care | 2022 |
| Ayaanah & Co Ltd | Wholesale & retail | 2019 |
| AYJ Removals Ltd | Transport & logistics | 2015 |
| Aylings Property Partnership LLP | | 2017 |
| Aylwins Management Company Limited | Households | 2011 |
| AYN Engineering Ltd | Administrative & support | 2026 |
| Aysa Medica Ltd | Health & social care | 2014 |
| AZ Luxury Travel Ltd | Transport & logistics | 2023 |
| Azimuth Building Services Limited | Construction | 1993 |
| Azizi Group Ltd | Real estate | 2025 |
| AZM Properties Limited | Construction | 2018 |
| Azra Consulting Ltd | Construction | 2018 |
| Azur International Trade Limited | Transport & logistics | 2025 |
| Azure Financial Services Limited | Professional & scientific | 2008 |
| Azzi Cleaningz Limited | Administrative & support | 2026 |
| B & White Ltd | Financial services | 2017 |
| B J Raishbrook Brickwork Limited | Construction | 2008 |
| B P W Consultancy Limited | Professional & scientific | 1990 |
| B. M. D. Security Limited | Construction | 2003 |
| B.A Decorating Services Ltd | Construction | 2021 |
| B.E.C.P.S. Limited | Administrative & support | 2009 |
| B.R. Investments Limited | Real estate | 2000 |
| B80 Ltd | Hospitality | 2026 |
| BA Restaurants Limited | Hospitality | 2018 |
| Babygirl Records Ltd | Arts & recreation | 2023 |
| Back Then Digital Limited | Information & communication | 2020 |
| Backbeat Media Services Ltd | Professional & scientific | 2019 |
| Backrow Consulting Ltd | Professional & scientific | 2006 |
| Backstreet International Merchandise Limited | Wholesale & retail | 1991 |
| Backyard Design Studios Limited | Professional & scientific | 2008 |
| BAD Behaviour Films Ltd | Professional & scientific | 2020 |
| Baers Repairs Ltd | Professional & scientific | 2022 |
| BAG That Gift Ltd | Wholesale & retail | 2024 |
| BAI Corporate Holdings Ltd | Financial services | 2024 |
| Bailey Gough Limited | Real estate | 2026 |
| Bajaj Brothers UK Ltd | Wholesale & retail | 2015 |
| Baker House Builders Limited | Construction | 2002 |
| Baker Roofing and Construction Company Limited | Construction | 1983 |
| Baker Street Venture Partners LLP | | 2018 |
| Baker Street Ventures Capital LLP | | 2017 |
| Baker Trade Finishers Limited | Administrative & support | 2007 |
| Baksh Enterprise Limited | Real estate | 2016 |
| Bala Management Company Ltd | Households | 2022 |
| Balaclava Road Residents Limited | Households | 2009 |
| Balance Medical Aesthetics Ltd | Other services | 2024 |
| Balfour House (Epsom) Management Company Limited | Households | 2004 |
| Balham Glass Ltd | Manufacturing | 2018 |
| Balham Group Ltd | Water & waste | 2023 |
| Balham Waste Management Ltd | Water & waste | 2023 |
| Ballin-Official Limited | Information & communication | 2025 |
| Balmoral Court (Cheam) Management Limited | Households | 1994 |
| Balmores (UK) Ltd | Extraterritorial | 2024 |
| Bambella Ltd | Wholesale & retail | 2026 |
| Bamboo Basket Ltd | Hospitality | 2010 |
| Bankside (Epsom Downs) Management Company Limited | Households | 2010 |
| Bankside Trading Ltd | Wholesale & retail | 2020 |
| Banstead Glass & Glazing Services Limited | Construction | 2012 |
| Banstead Motor Repairs Limited | Administrative & support | 2017 |
| Banstead Wood Management Company Limited | Households | 2006 |