| Advance Consulting Group Limited | Professional & scientific | 2011 |
| Advance DPF Solutions Ltd | Manufacturing | 2017 |
| Advance Export Certification Ltd | Professional & scientific | 2021 |
| Advance Residential Management Limited | Real estate | 2014 |
| Advance Safety Netting UK Ltd | Construction | 2021 |
| Advanced Aesthetics by Nikola Ltd | Other services | 2025 |
| Advanced Cable Installations Ltd. | Other services | 2014 |
| Advanced Coating (Services) Ltd | Manufacturing | 2009 |
| Advanced Communication Projects Limited | Administrative & support | 1998 |
| Advanced Energetic Materials Ltd | Professional & scientific | 2010 |
| Advanced Generation Contracts Ltd | Professional & scientific | 2020 |
| Advanced Generation Limited | Professional & scientific | 2015 |
| Advanced Hand to Shoulder Orthopaedics Limited | Health & social care | 2023 |
| Advanced Heat Management Solutions Ltd | Construction | 2022 |
| Advanced Homes Limited | Construction | 1982 |
| Advanced Joinery (UK) Limited | Manufacturing | 2015 |
| Advanced Labelling Limited | Wholesale & retail | 2005 |
| Advanced Machine Services Ltd | Manufacturing | 2015 |
| Advanced Machining Solutions Limited | Professional & scientific | 2009 |
| Advanced Marble and Granite UK Limited | Manufacturing | 2000 |
| Advanced Medcare Ltd | Health & social care | 2019 |
| Advanced Medpharma Ltd | Professional & scientific | 2026 |
| Advanced Mobility Services Limited | Transport & logistics | 2024 |
| Advanced Pharmacare Ltd | Health & social care | 2013 |
| Advanced Planning Ltd | Real estate | 2015 |
| Advanced Practice and Mentorship Ltd | Health & social care | 2021 |
| Advanced Quality Solutions Limited | Wholesale & retail | 1977 |
| Advanced Real Estate Group Ltd | Hospitality | 2025 |
| Advanced Roofing (Yorkshire) Ltd | Construction | 2015 |
| Advanced Seating (UK) Limited | Manufacturing | 2011 |
| Advanced Security Partners Limited | Administrative & support | 2006 |
| Advanced Structural Detailing Limited | Information & communication | 2017 |
| Advanced Thermal Ltd | Construction | 2024 |
| Advanced Trading and Logistics Ltd | Transport & logistics | 2025 |
| Advanced Wiring Systems Limited | Construction | 2012 |
| Advancelocumagency Limited | Health & social care | 2023 |
| Advantage Antiques & Watches Ltd | Wholesale & retail | 2020 |
| Advantage Crowd Management Services Ltd | Administrative & support | 2021 |
| Advantage Electrical Solutions Ltd | Construction | 2025 |
| Advantage Mortgage Services (Yorkshire) Limited | Financial services | 2004 |
| Advantage Property Lawyers Limited | Professional & scientific | 2008 |
| Advantage Sport (Licenses) Limited | Wholesale & retail | 2013 |
| ADVANTAGE42 Limited | Administrative & support | 2009 |
| Advaskin Limited | Professional & scientific | 2006 |
| Advenco Blinds and Shutters Ltd | Wholesale & retail | 2023 |
| Adventura (Leeds) Ltd | Arts & recreation | 2024 |
| Adventure Conversions and Sales Limited | Wholesale & retail | 2025 |
| Adventure Families Limited | Other services | 2023 |
| Adventure Leisure Vehicles Ltd | Wholesale & retail | 2005 |
| Adventure Philanthropy Limited | Administrative & support | 2014 |
| Adventurex Limited | Information & communication | 2005 |
| Adventuriada Ltd | Administrative & support | 2024 |
| Advertising Principles Holdings Limited | Professional & scientific | 2012 |
| Advertising Stands Limited | Wholesale & retail | 2011 |
| Adverto Management Ltd | Hospitality | 2025 |
| Advice Champion Services Limited | Financial services | 2019 |
| Advice Champion.Co.Uk Limited | Financial services | 2011 |
| Advisarex Limited | Information & communication | 2025 |
| Advise Wise Limited | Information & communication | 2018 |
| Advisily Ltd | Professional & scientific | 2025 |
| Advisory Consultant Limited | Professional & scientific | 2024 |
| Advocate Solutions Ltd | Professional & scientific | 2024 |
| Advonet | Health & social care | 2001 |
| ADW Veyron Limited | Information & communication | 2017 |
| Adws Solutions Limited | Wholesale & retail | 2024 |
| ADY Gangal Ltd | Transport & logistics | 2026 |
| ADY Properties Ltd | Real estate | 2023 |
| ADY Rosario Ltd | Wholesale & retail | 2022 |
| Adymon Limited | Transport & logistics | 2020 |
| Adyna Ltd | Professional & scientific | 2013 |
| ADZ Property Management Limited | Real estate | 2019 |
| Adzenon Ltd | Information & communication | 2022 |
| AE (2013) Limited | Extraterritorial | 2013 |
| AE 2009 Limited | Manufacturing | 1979 |
| AE Adewuyi Consulting Ltd | Professional & scientific | 2012 |
| AE Collective Ltd | Professional & scientific | 2026 |
| AE Dental Ltd | Health & social care | 2022 |
| AE MED Limited | Health & social care | 2022 |
| AEA Investments Leeds Ltd | Real estate | 2023 |
| AEC Electrical Contractors Limited | Construction | 2004 |
| Aedif Projects Limited | Professional & scientific | 2012 |
| Aedk Holdings Ltd | Financial services | 2023 |
| AEG Property Services Ltd | Real estate | 2025 |
| Aegis Care Group Limited | Health & social care | 2023 |
| Aegis Care Homes Limited | Health & social care | 2024 |
| Aegis Care Solutions Limited | Health & social care | 2016 |
| Aegis Endurance Limited | Information & communication | 2025 |
| Aegis Franchise Ltd | Health & social care | 2024 |
| Aegis Leeds East LLP | | 2016 |
| Aegis Leeds South LLP | | 2019 |
| AEI Building and Construction Ltd | Construction | 2023 |
| AEI Building Solutions Ltd | Construction | 2023 |
| Aejg Ltd | Health & social care | 2023 |
| AEM Holdings Ltd | Real estate | 2025 |
| AEM Range Cookers Limited | Other services | 2022 |
| Aemra Ltd | Information & communication | 2026 |
| Aenean Labs Limited | Information & communication | 2025 |
| AEP Horticulture Ltd | Administrative & support | 2022 |
| Aequitas Solicitors Limited | Professional & scientific | 2024 |
| Aere Property Limited | Real estate | 2025 |