| Alcaufar Limited | Financial services | 2024 |
| Alchemilla Restaurant Ltd | Hospitality | 2024 |
| Alchemist Fabrications Limited | Manufacturing | 2025 |
| Alchemy Compliance Limited | Professional & scientific | 2001 |
| Alcocks Property Lawyers Limited | Professional & scientific | 2009 |
| ALD Estates Limited | Real estate | 2024 |
| ALD Facades Holdings Limited | Construction | 2025 |
| ALD Flat Roofing Limited | Construction | 2024 |
| ALD Floor Screed Limited | Construction | 2023 |
| ALD Groupco Limited | Construction | 2025 |
| ALD Properties and Investments Ltd | Real estate | 2025 |
| Aldebaran Beauty Ltd | Wholesale & retail | 2025 |
| Alder Country Park Ltd | Real estate | 2021 |
| Alder Court Management Company Limited | Real estate | 2001 |
| Aldercar and Langley Mill Action Group CIC | Health & social care | 2025 |
| Aldergate Developments Limited | Construction | 1992 |
| Aldergate Estates Limited | Construction | 1992 |
| Aldergate Land Limited | Construction | 1993 |
| Aldergate Projects Limited | Real estate | 1992 |
| Aldergate Properties Limited | Real estate | 1991 |
| Aldergate Realties Ltd. | Real estate | 1993 |
| Alderley Park Ventures Limited | Financial services | 2014 |
| Aldonai Group Limited | Financial services | 2024 |
| Aldonai Logistics Ltd | Transport & logistics | 2023 |
| Aldora (Nottingham) Limited | Health & social care | 2013 |
| Aldr Ltd | Information & communication | 2025 |
| Aldred and Aldred Limited | Real estate | 2014 |
| Aldred Developments Limited | Construction | 2014 |
| Aldreds the Bakers Limited | Manufacturing | 2017 |
| Aldridge Ventures Limited | Professional & scientific | 2026 |
| Aldwark Bridge Limited | Administrative & support | 2000 |
| Aldwark Toll LLP | | 2016 |
| Alect Limited | Construction | 2025 |
| Alegre Investments Limited | Financial services | 2024 |
| Alegria Ltd | Manufacturing | 2015 |
| Alegs Ltd | Real estate | 2025 |
| Alekta Homes Ltd | Real estate | 2022 |
| Alem Art Limited | Administrative & support | 2019 |
| Alerion Collective Limited | Information & communication | 2025 |
| Alero Technology Ltd | Information & communication | 2026 |
| Alert Electrical Wholesalers Holdings Limited | Financial services | 2010 |
| Alert Electrical Wholesalers Limited | Wholesale & retail | 1996 |
| Alert Fire Protection Limited | Construction | 2025 |
| Alert PPM Limited | Professional & scientific | 2011 |
| Alethra Ltd | Professional & scientific | 2026 |
| Alex and Ian's Creations Ltd | Wholesale & retail | 2024 |
| Alex Cassi Ltd | Transport & logistics | 2022 |
| Alex Chick Dressage Ltd | Education | 2025 |
| Alex Collier Electricity Distribution Ltd | Construction | 2025 |
| Alex James Studio Ltd | Professional & scientific | 2025 |
| Alex Lindley Limited | Professional & scientific | 2022 |
| Alex Mcintyre Architects Limited | Professional & scientific | 2003 |
| Alex Nelson Design Ltd | Professional & scientific | 2025 |
| Alex Properties (2016) Limited | Real estate | 2016 |
| Alex Squared Ltd | Professional & scientific | 2023 |
| Alex Stark Limited | Wholesale & retail | 2024 |
| Alex Thompson Limited | Other services | 2012 |
| Alex Wilkinson Media Limited | Information & communication | 2017 |
| Alexa Beauty Services Limited | Other services | 2023 |
| Alexahub Ltd | Real estate | 2026 |
| Alexander & Short Ltd | Real estate | 2017 |
| Alexander & William Limited | Manufacturing | 2025 |
| Alexander and SON Electrical Services Ltd | Construction | 2025 |
| Alexander Beardsley Consultancy Ltd | Professional & scientific | 2025 |
| Alexander Cameron (UK) Limited | Real estate | 2006 |
| Alexander Freeholdings Limited | Real estate | 2021 |
| Alexander Harding Estate Agent Limited | Real estate | 2025 |
| Alexander Perotti Limited | Wholesale & retail | 2020 |
| Alexander Real Estates and Lettings Limited | Real estate | 2024 |
| Alexander-Aquino Group Ltd | Information & communication | 2023 |
| Alexander-Mason Property Group Ltd | Real estate | 2021 |
| Alexandra Bakery Notts Ltd | Wholesale & retail | 2019 |
| Alexandra Building Services Ltd | Real estate | 2000 |
| Alexandra Court (Nottingham) RTM Company Limited | Other services | 2011 |
| Alexandra Giorga Limited | Health & social care | 2026 |
| Alexandra Kalogeropoulou Therapies Ltd | Health & social care | 2026 |
| Alexandra Law Limited | Professional & scientific | 2023 |
| Alexandra UK Developments Limited | Construction | 2021 |
| Alexandra UK Properties Limited | Real estate | 2021 |
| Alexandra UK Property Management Limited | Real estate | 2021 |
| Alexhar Ltd | Wholesale & retail | 2022 |
| Alexia Packaging Ltd | Administrative & support | 2019 |
| Alexis Consultancy Ltd | Professional & scientific | 2013 |
| Alexsta Trans Spółka Z Ograniczoną Odpowiedzialnością Ltd | Wholesale & retail | 2025 |
| Alex’S Barber Studio Ltd | Other services | 2025 |
| Aleyahs Blinds Ltd | Construction | 2023 |
| ALF & Co (UK) Ltd | Wholesale & retail | 2019 |
| Alfa GAS Limited | Construction | 2015 |
| Alfa IT Consulting Ltd | Information & communication | 2014 |
| Alfaraff Design Ltd | Professional & scientific | 2019 |
| Alficina Ltd | Wholesale & retail | 2021 |
| Alfors Engineering Ltd | Professional & scientific | 2026 |
| Alfred Thomas Property Ltd | Real estate | 2019 |
| Alfreton Hall Limited | Hospitality | 2007 |
| Alfreton Road Lets Limited | Real estate | 2024 |
| Alfreton Road Property Management Services Limited | Households | 2005 |
| Alfreton Trading Ltd | Hospitality | 2020 |
| Alfx Ltd | Manufacturing | 2015 |
| ALG Group Holdings Limited | Construction | 2022 |
| Algarde Enterprises Limited | Extraterritorial | 1975 |