| Aarmax Limited | Real estate | 2023 |
| Aaron Leesam Properties Limited | Real estate | 2005 |
| Abbey Cross Glass Ltd | Construction | 2015 |
| Abbey Smoke and BBQ Ltd | Hospitality | 2026 |
| Abbuilding Contractors Ltd | Construction | 2020 |
| ABC Learning 25 Ltd | Education | 2025 |
| ABD Sparks Ltd | Construction | 2025 |
| Abdullah Properties Limited | Real estate | 2025 |
| Abdullah's Group Limited | Hospitality | 2021 |
| Abel Recruitment Ltd | Extraterritorial | 2020 |
| Abercraft Drivers Ltd | Transport & logistics | 2014 |
| ABI Building Services Ltd | Construction | 2024 |
| Abidin Barbers Ltd | Other services | 2020 |
| Abode E3 Management Limited | Construction | 2013 |
| About Cooling Limited | Construction | 2007 |
| About Electrical Limited | Extraterritorial | 2019 |
| About Mechanical Limited | Extraterritorial | 2019 |
| Abpp Limited | Real estate | 2026 |
| ABS Academy Limited | Education | 2024 |
| Abstract Worx Limited | Information & communication | 2020 |
| Abvprotect Ltd | Wholesale & retail | 2015 |
| AC Concierge Ltd | Administrative & support | 2024 |
| AC Technical Solutions Limited | Information & communication | 2024 |
| Acceptlink Limited | Wholesale & retail | 1998 |
| Accos Limited | Information & communication | 2008 |
| Accountancy Solutions Euro Limited | Professional & scientific | 2002 |
| Accra Digital Limited | Information & communication | 2012 |
| Accurate Cleaning Services Limited | Households | 2019 |
| Ace Catering Suppliers Limited | Hospitality | 2005 |
| Ace Performance Group Limited | Wholesale & retail | 2024 |
| Ace Performance Holdings Limited | Wholesale & retail | 2024 |
| Ace Threadworks Ltd | Manufacturing | 2026 |
| Ace Waste Ltd | Water & waste | 2025 |
| Ace-Pro Heating & Plumbing Ltd | Construction | 2013 |
| Acea Perfect Ltd | Construction | 2021 |
| Aces Investments Ltd | Real estate | 2026 |
| ACESHARE1 Ltd | Extraterritorial | 2023 |
| Aceso Healthcare Recruitment Limited | Administrative & support | 2018 |
| ACH Land Limited | Financial services | 2022 |
| Achievers Support CIC | Administrative & support | 2019 |
| Acil Properties Ltd | Real estate | 2019 |
| Acorn Web Group Ltd | Information & communication | 2023 |
| Acorns Solutions Limited | Financial services | 2015 |
| ACP General Builders Ltd | Construction | 2009 |
| Actions for Changes Community CIC | Education | 2021 |
| Active Management Ltd | Professional & scientific | 2025 |
| Acuity Contact Lenses Limited | Extraterritorial | 2007 |
| AD Mechanical, Plumbing & Heating Ltd | Construction | 2024 |
| ADA - March Connect Ltd. | Wholesale & retail | 1994 |
| ADA Aesthetics Ltd | Other services | 2020 |
| ADA Car Consultancy Limited | Administrative & support | 2021 |
| ADA Jewellery Limited | Manufacturing | 2026 |
| Adae Properties Limited | Real estate | 2013 |
| Adael Limited | Hospitality | 2024 |
| ADD Another Level Limited | Construction | 2023 |
| ADD Property Management Ltd | Real estate | 2021 |
| Adel Property Lettings Ltd | Real estate | 2024 |
| Adeola Gboyega Ltd | Other services | 2021 |
| Adonai Ltd | Information & communication | 2015 |
| Adrenaline Sports C.I.C. | Education | 2018 |
| Aduspenny Contract Services Ltd | Administrative & support | 2015 |
| Advance Abseiling Ltd | Administrative & support | 2020 |
| Advance Home Help & Support Services Ltd | Health & social care | 2019 |
| Advanced Healthcare Technology Limited | Manufacturing | 1992 |
| Advanced Printing Solutions Ltd | Administrative & support | 2021 |
| ADY Drive Ltd | Wholesale & retail | 2020 |
| AE & JA Property Limited | Real estate | 2026 |
| Aehosh Properties Ltd | Construction | 2018 |
| Aeiforia UK Ltd | Wholesale & retail | 2026 |
| AEP Property Investment Ltd | Real estate | 2023 |
| Aerial & Satellite Installations Limited | Other services | 2007 |
| Aerospace Innovations Media LLP | | 2024 |
| AF Trans Ltd | Transport & logistics | 2021 |
| AFA Meat Ltd | Wholesale & retail | 2021 |
| AFD Inspections Limited | Public administration | 2022 |
| Afena Trading Limited | Administrative & support | 2025 |
| Affiliate IQ Ltd | Information & communication | 2026 |
| Affinity Azure Limited | Construction | 2025 |
| Affirm Hold Limited | Administrative & support | 2006 |
| Africa Mediaworks Limited | Information & communication | 2017 |
| Afrique Spirits Limited | Wholesale & retail | 2023 |
| AG & PW Ventures Ltd | Real estate | 2020 |
| AG Property Enterprise Ltd | Real estate | 2018 |
| AGA Import Limited | Wholesale & retail | 2018 |
| AGD Interiors Limited | Construction | 2025 |
| Aggie V Limited | Wholesale & retail | 2023 |
| AGI AI Solutions Ltd | Information & communication | 2023 |
| AH Evergreen Limited | Arts & recreation | 2024 |
| AHK Brecons LLP | | 2022 |
| Ahmati Cleaning Ltd | Administrative & support | 2023 |
| Ahmati Properties Ltd | Real estate | 2023 |
| AHS Builders Limited | Construction | 2026 |
| AI Executive Transport Limited | Transport & logistics | 2024 |
| AI Integration Ltd | Information & communication | 2024 |
| Aims Offer Eternity Records Limited | Information & communication | 2020 |
| Aine LDN Limited | Wholesale & retail | 2025 |
| Air IT Consultants Limited | Administrative & support | 2013 |
| AJ Angelo George Law Ltd | Professional & scientific | 2018 |
| AJ Bond Limited | Information & communication | 2023 |
| AJC Ltd | Financial services | 2023 |