| Aden Fletcher Investments Ltd | Real estate | 2023 |
| Aden Specialist Trades Ltd. | Construction | 2009 |
| Adengate Limited | Transport & logistics | 2002 |
| Adensi Limited | Professional & scientific | 2006 |
| Adeon LP | | 2014 |
| Adept Holdings Ltd | Wholesale & retail | 2018 |
| Adept Optical Ltd | Professional & scientific | 2011 |
| Aderta Business LP | | 2016 |
| Adesanya&Co Limited | Construction | 2008 |
| Adex Consulting Ltd | Information & communication | 2010 |
| Adfak Guvyshow Sport and Academy Limited | Health & social care | 2019 |
| Adfc Limited | Other services | 2001 |
| ADG Manufacturing Limited | Manufacturing | 2025 |
| ADG Prefcap Founder GP LLP | | 2021 |
| ADG Prefcap Founder LP | | 2021 |
| Adhddegree Ltd | Health & social care | 2024 |
| Adhero Systems Limited | Information & communication | 2026 |
| ADI & Aarvi Hospitality Ltd | Hospitality | 2025 |
| ADI & Aarvi Investment Ltd | Real estate | 2024 |
| ADI Motors Ltd | Wholesale & retail | 2025 |
| Adideait Ltd | Information & communication | 2024 |
| Adie Investment Trading (Scotland) Partnership SP | | 2022 |
| Adilake Management LP | | 2014 |
| Adimo Tech Ltd | Information & communication | 2025 |
| Adina Sales LP | | 2018 |
| Adington Synergy LP | | 2016 |
| Adinmo Ltd | Information & communication | 2019 |
| Adintense L.P. | | 2014 |
| Adiona Logistics Limited | Transport & logistics | 2021 |
| Adira Jewel Limited | Wholesale & retail | 2020 |
| Aditi TEC Ltd | Information & communication | 2010 |
| Aditya Retail Limited | Wholesale & retail | 2026 |
| Aditya Scott Retail Ltd | Wholesale & retail | 2026 |
| Aditya Stores Limited | Wholesale & retail | 2026 |
| Adiwer LP | | 2021 |
| Adjem Ltd | Financial services | 2018 |
| Adjustlight Limited | Hospitality | 1992 |
| ADL Sourcing and Trading Ltd | Wholesale & retail | 2026 |
| Adlatabaco Limited | Construction | 2024 |
| Adler Wind Lidar Limited | Professional & scientific | 2023 |
| Adlevo Ltd | Administrative & support | 2015 |
| ADM Application Support Limited | Information & communication | 2025 |
| ADM Digital Solutions Ltd | Professional & scientific | 2026 |
| ADM Engineering Consultancy Limited | Professional & scientific | 2015 |
| ADM International Ltd | Real estate | 2019 |
| ADM Pharma Ltd | Wholesale & retail | 2026 |
| Admargin Limited | Information & communication | 2011 |
| Admin Agency L.P. | | 2014 |
| Admin Corporation L.P. | | 2010 |
| Administrate Limited | Information & communication | 2007 |
| Admiral Associates L.P. | | 2014 |
| Admiral Business LP | | 2013 |
| Admiral Choice LP | | 2016 |
| Admiral Enterprises L.P. | | 2009 |
| Admiral Glory LP | | 2017 |
| Admiral Industries L.P. | | 2008 |
| Admiral Joinery Limited | Other services | 2018 |
| Admiral Technology L.P. | | 2012 |
| Admiral Trading Technology LP | | 2015 |
| Admiralty Trans LLP | | 2008 |
| Admire Trade LP | | 2014 |
| Admissions Support Ltd | Information & communication | 2023 |
| Admt Limited | Information & communication | 2012 |
| Adnan & Aysha Arshad Limited | Professional & scientific | 2018 |
| Adnan Limited | Other services | 2014 |
| Adnan Motors Ltd | Transport & logistics | 2023 |
| Adobe Systems Europe Limited | Administrative & support | 1986 |
| Adomako Accountancy Limited | Professional & scientific | 2014 |
| Adop Services | | 1994 |
| Adopt an Intern Ltd | Professional & scientific | 2012 |
| ADOPT6 Ltd | Professional & scientific | 2026 |
| Adoris Invest LP | | 2016 |
| Adorx Therapeutics Limited | Professional & scientific | 2017 |
| Adpc Property Care Ltd | Construction | 2014 |
| Adpk Ltd | Information & communication | 2025 |
| Adpromoco LP | | 2017 |
| ADR Hospitality Group Limited | Professional & scientific | 2018 |
| ADR Operations Ltd | Information & communication | 2019 |
| Adra Trading Ltd | Transport & logistics | 2022 |
| Adrestia Capital Partners (TCC) LLP | | 2020 |
| Adrestia Capital Partners Limited | Professional & scientific | 2017 |
| Adrestia Coinvest 2020 LLP | | 2020 |
| Adrestia Management Services LLP | | 2020 |
| Adret Gibs Limited | Manufacturing | 2004 |
| Adria Commerce LP | | 2016 |
| Adrian Mead Ltd. | Arts & recreation | 2001 |
| Adrian Systems LP | | 2014 |
| Adriana Boffa - Tour Guide Ltd | Administrative & support | 2026 |
| Adriano Sound Ltd | Arts & recreation | 2025 |
| Adriaus Limited | Information & communication | 2012 |
| Adriaus Technology Services Ltd | Information & communication | 2018 |
| Adriver MD Limited | Construction | 2021 |
| Adroit Casinos LP | | 2014 |
| ADS Business Consulting L.P. | | 2014 |
| ADS Power Ltd | Professional & scientific | 2022 |
| Adsbalance LP | | 2017 |
| Adserv Ltd | Administrative & support | 2026 |
| Adspannu Ltd | Real estate | 2023 |
| Adsvantage Scale LP | | 2025 |
| ADT Corporation LLP | | 2017 |