| Accountancy 2U Ltd | Professional & scientific | 2020 |
| Accsj Property Ltd | Real estate | 2026 |
| Accura U.K. Limited | Real estate | 2014 |
| Ace Academic Tutors Ltd | Education | 2024 |
| Ace Food Hub Ltd | Hospitality | 2025 |
| ACM Trade and Freight Ltd | Other services | 2024 |
| Acoco Service Enterprise Limited | Health & social care | 2023 |
| Actionpoint | | 1984 |
| Acts SIX Ltd | Real estate | 2023 |
| Actus Healthcare Limited | Information & communication | 2015 |
| ADA Plumbing Ltd | Construction | 2025 |
| Adah Designs Ltd | Professional & scientific | 2024 |
| Adam Prestige Motors Ltd | Wholesale & retail | 2022 |
| Adam Sinclair Limited | Wholesale & retail | 1995 |
| Addicted to Football Ltd | Education | 2025 |
| Adek Studios Limited | Professional & scientific | 2021 |
| Adesina Asumo Auto Sales Ltd | Wholesale & retail | 2021 |
| Adirose Learning Limited | Education | 2026 |
| ADJ Production Limited | Construction | 2021 |
| ADJ Removals Ltd | Transport & logistics | 2014 |
| ADK Childcare Ltd | Health & social care | 2023 |
| ADM London Ltd | Real estate | 2020 |
| Adnest Interlink Ltd | Real estate | 2023 |
| ADU Homes Ltd | Households | 2021 |
| Adudaniels Ltd | Other services | 2026 |
| Adun Music Ltd | Arts & recreation | 2024 |
| Aduniniyi 7 Property Investment Limited | Real estate | 2022 |
| Adurja Services Ltd | Professional & scientific | 2025 |
| ADV Dubb Contractors Ltd | Construction | 2026 |
| Advance Secured Solutions Ltd | Professional & scientific | 2014 |
| Advanced Professional Plumbing and Heating Services Limited | Manufacturing | 2008 |
| Advanced Vehicle Cleaning Supplies Ltd | Administrative & support | 2004 |
| Advancehomeservice Ltd | Administrative & support | 2023 |
| Advantages Properties Ltd | Real estate | 2024 |
| Advoaid Consult Ltd | Administrative & support | 2025 |
| Adworks Growth Ltd | Professional & scientific | 2026 |
| ADY Construction & WORK1 Limited | Construction | 2021 |
| AE Builders Ltd | Construction | 2019 |
| Aeeij Healthcare Ltd | Health & social care | 2023 |
| Aeeiw Ltd | Construction | 2023 |
| AEO Ventures Ltd | Transport & logistics | 2025 |
| Aetos Properties Ltd | Real estate | 2025 |
| Aets Health Limited | Health & social care | 2024 |
| AF Tech Solutions Ltd | Wholesale & retail | 2025 |
| Afford Clean Services Limited | Water & waste | 2021 |
| Afifs Trading Co. Limited | Wholesale & retail | 2026 |
| Afriz Limited | Wholesale & retail | 2023 |
| Afro Commodities (UK) Limited | Administrative & support | 2007 |
| Afro Miam Ltd | Hospitality | 2025 |
| Afrohairtransplant Ltd | Administrative & support | 2026 |
| Afroturf Limited | Extraterritorial | 2018 |
| AG Mold Joinery Ltd | Manufacturing | 2026 |
| AG SAI Properties Ltd | Real estate | 2025 |
| Agapeglobal Professional Services Limited | Information & communication | 2010 |
| AGB Consultants Limited | Real estate | 2015 |
| AGE Installs Ltd | Construction | 2021 |
| Agedearth Limited | Information & communication | 2022 |
| Agga Construction Ltd | Construction | 2023 |
| Agnius.V Limited | Manufacturing | 2025 |
| AGO Multi Concept Ltd | Hospitality | 2024 |
| Agrimist Limited | Real estate | 1996 |
| Agrobase Trading Limited | Agriculture & fishing | 2011 |
| AH Real Estates Ltd | Real estate | 2019 |
| AH Web Portal Limited | Information & communication | 2024 |
| Ahia Care Home Ltd | Health & social care | 2022 |
| Ahuja Transport Ltd | Transport & logistics | 2025 |
| AI Professionals Ltd | Wholesale & retail | 2024 |
| AIC Electrical Installations Limited | Construction | 2016 |
| Aico Logistics and Customs Limited | Transport & logistics | 2018 |
| AIM High Expeditions LLP | | 2019 |
| Aircon EXE Ltd | Construction | 2023 |
| Airees Ltd | Professional & scientific | 2020 |
| Aitvaras Ltd | Education | 2024 |
| AJ Catering Engineers Ltd | Manufacturing | 2019 |
| Ajac Properties Limited | Real estate | 1997 |
| Ajbconcrete Ltd | Construction | 2025 |
| AJG Care Services Limited | Health & social care | 2025 |
| AK Auto Security Limited | Administrative & support | 2025 |
| AK Auto Spot Ltd | Wholesale & retail | 2024 |
| AK Motors & Engineering Ltd | Other services | 2008 |
| AKK Holdings Limited | Real estate | 2016 |
| AKM Group Worldwide Ltd | Information & communication | 2019 |
| AL Arab Publishing Limited | Information & communication | 2025 |
| AL Raeem Universal Ltd | Wholesale & retail | 2023 |
| Al-Abaja Properties Ltd | Real estate | 2021 |
| Alam Associates Limited | Education | 2017 |
| Alantic GLO Ltd | Administrative & support | 2017 |
| Alasunkem Integrated Services Limited | Real estate | 2025 |
| Albe Limited | Construction | 2011 |
| Albion Construction Services Ltd | Construction | 2025 |
| Alborough Digital Solutions Ltd | Information & communication | 2024 |
| Albright Transfer Station Limited | Water & waste | 1999 |
| Alemo Realty Group Ltd | Real estate | 2025 |
| Alesar Limited | Wholesale & retail | 2022 |
| Alex ATS Group Ltd | Administrative & support | 2023 |
| Alex Top Services Ltd | Construction | 2015 |
| Alex VIN DEV Limited | Construction | 2021 |
| Alferd Property Services Limited | Energy | 2017 |
| ALI 110 Ltd | Transport & logistics | 2020 |
| ALI Fadezz Limited | Other services | 2024 |