| Arwem Food Distribution UK Limited | Administrative & support | 2010 |
| Ashland Limited | Households | 1981 |
| Ashoka Estate Ltd | Real estate | 2019 |
| Ashutosh Ltd | Real estate | 2023 |
| Asmar Services Limited | Professional & scientific | 2019 |
| ASN Chadha Partnership LLP | | 2017 |
| Astern Ltd | Administrative & support | 2021 |
| Aston-Med Limited | Wholesale & retail | 2012 |
| Aston-Medical Limited | Extraterritorial | 2013 |
| Astoria Ventures Limited | Real estate | 2024 |
| Astra One Ltd | Real estate | 2016 |
| Astra Property Investments Ltd | Real estate | 2005 |
| Astra Two Limited | Real estate | 2018 |
| Astwood Place Freehold Limited | Administrative & support | 2009 |
| Astwood Place RTM Company Limited | Administrative & support | 2004 |
| Atheli Ltd | Construction | 2025 |
| Atrium Events LLP | | 2019 |
| August Associates Ltd | Wholesale & retail | 2020 |
| Aurexon Properties Limited | Real estate | 2026 |
| Aurum Prime Gateway Ltd | Wholesale & retail | 2026 |
| Austin Akanni Limited | Real estate | 2002 |
| Auto Trade Solutions 2 Ltd | Wholesale & retail | 2025 |
| Autofast (Caterham) Ltd | Wholesale & retail | 2004 |
| Auxilium Partners Limited | Professional & scientific | 2016 |
| Avant Food Ltd | Hospitality | 2022 |
| Aveling Close Residents Association Limited | Real estate | 1984 |
| Aventine Limited | Administrative & support | 2012 |
| Aventine Royale Ltd | Wholesale & retail | 2025 |
| AVG Drylining Ltd | Construction | 2007 |
| Avocado Capital Limited | Financial services | 2022 |
| Avosc Consulting Limited | Professional & scientific | 2023 |
| Avsm Services Ltd | Professional & scientific | 2002 |
| AVT Holdings Limited | Real estate | 2016 |
| Axeli Ltd | Wholesale & retail | 2018 |
| Axia Properties Limited | Construction | 2017 |
| Axil Capital Limited | Financial services | 2022 |
| Aycorn Shoppe Limited | Wholesale & retail | 2023 |
| AYE Consult Ltd | Professional & scientific | 2023 |
| AYE Estates Ltd | Construction | 2022 |
| Ayokunle Ltd | Real estate | 2023 |
| Ayub Childcare Services Ltd | Education | 2023 |
| Ayub Real Estate Limited | Real estate | 2021 |
| Azadii Ltd | Health & social care | 2023 |
| B & H Property Investment Limited | Real estate | 2024 |
| B & M Resinvest Limited | Real estate | 2022 |
| B Taylor Surveying & Construction Services Ltd | Professional & scientific | 2006 |
| B.A Health Group Ltd | Health & social care | 2021 |
| Baba's Catering & Takeaway Ltd | Hospitality | 2024 |
| Bachue Group Ltd | Wholesale & retail | 2026 |
| BAD ZOO Ltd | Professional & scientific | 2024 |
| Badmarsh Publishing Ltd | Information & communication | 2024 |
| Bahelmi Consultancy Ltd | Professional & scientific | 2023 |
| Bailey Endeavours Ltd | Professional & scientific | 2012 |
| Banstead Property Investments Limited | Real estate | 2013 |
| Baos and Bites Ltd | Hospitality | 2023 |
| Barakah Health Ltd | Health & social care | 2021 |
| Barclay House Investments Ltd | Real estate | 2021 |
| Barclay House LLP | | 2010 |
| Barden Strategic Alignments Limited | Education | 2007 |
| Barry Lehec Ltd | Real estate | 2017 |
| Barted Properties Limited | Real estate | 2019 |
| Basoah Consulting Ltd | Professional & scientific | 2016 |
| Batf the Pink Palace CIC | Hospitality | 2026 |
| Baxter Advice Services Ltd | Financial services | 2011 |
| Bblacqnation Ltd | Transport & logistics | 2024 |
| Bbqforyou Ltd | Wholesale & retail | 2016 |
| Bcdr Investments Ltd | Real estate | 2022 |
| BE Spring Ltd. | Information & communication | 2015 |
| Beaufort Court RTM Company Ltd | Households | 2024 |
| Beauty and the Feast Ltd | Hospitality | 2022 |
| Bebedi Limited | Information & communication | 2011 |
| Beddington Limited | Real estate | 2020 |
| Beechy Clean Windows Limited | Administrative & support | 2012 |
| Beeing Social IT & Consulting Limited | Information & communication | 2022 |
| Bega Lighting UK Limited | Other services | 2014 |
| Beingt Limited | Professional & scientific | 2024 |
| Belfort Consulting Ltd | Professional & scientific | 2017 |
| Bellamy's (South East) Limited | Wholesale & retail | 2019 |
| Bellar Limited | Wholesale & retail | 2020 |
| Bellis Norway Limited | Extraterritorial | 2011 |
| Bellville Homes Ltd | Real estate | 2012 |
| Belvoir Heights Management Company Ltd | Households | 2024 |
| Benarii Ltd | Wholesale & retail | 2019 |
| Benefits Benchmarking Ltd | Information & communication | 2022 |
| Bensham Manor Community Association | Education | 2011 |
| Benzel Homes Ltd | Households | 2023 |
| Beqom UK Limited | Information & communication | 2009 |
| Berlin Flame Grill Ltd | Hospitality | 2025 |
| Berlin Grill Limited | Hospitality | 2026 |
| Berrycom Solutions Limited | Information & communication | 2008 |
| Besra Group Ltd | Real estate | 2024 |
| Best Foods Northampton Limited | Wholesale & retail | 2025 |
| Best Purley Barbers Ltd | Other services | 2018 |
| Bhu-Dev Partners Ltd | Wholesale & retail | 2024 |
| Bibi Media Limited | Administrative & support | 2022 |
| Big Butterfly Limited | Professional & scientific | 2020 |
| Bigal Limited | Information & communication | 2024 |
| Bigfin Technologies Ltd. | Agriculture & fishing | 2019 |
| Bish Bash Bosch Ltd | Professional & scientific | 2020 |
| Bite Size Limited | Education | 2007 |