| AJJ Technologies Limited | Information & communication | 2023 |
| AJK York Properties Ltd | Real estate | 2024 |
| Ajmal Estates Limited | Households | 2025 |
| Ajmal Medicare Limited | Health & social care | 2025 |
| AJO Commercial Properties Ltd | Real estate | 2015 |
| AJP Business Services Ltd | Professional & scientific | 2020 |
| AJR Joinery Ltd | Construction | 2005 |
| AJS Driver Services Ltd | Transport & logistics | 2015 |
| AJS Electrical Group Limited | Construction | 2021 |
| AJT Garden Services Ltd | Administrative & support | 2019 |
| AJW Advisory Limited | Financial services | 2023 |
| AK Hair Studio Ltd | Other services | 2021 |
| AK York Limited | Wholesale & retail | 2016 |
| AKC Management Services Limited | Professional & scientific | 2015 |
| Akei Ltd | Wholesale & retail | 2014 |
| Akemi Associates Ltd | Professional & scientific | 2018 |
| Akgul Properties Ltd | Real estate | 2026 |
| Akin Clothing Ltd | Wholesale & retail | 2017 |
| AKM Enterprises Limited | Wholesale & retail | 1998 |
| AKM Estates Ltd | Real estate | 2022 |
| AKP Resources Ltd | Professional & scientific | 2020 |
| Aksp Lets Ltd | Hospitality | 2026 |
| Aksp Ltd | Real estate | 2024 |
| AKT Foods Ltd | Hospitality | 2026 |
| Akwan Valeting Ltd | Administrative & support | 2023 |
| AL - Rawi Anaesthetic Services Limited | Health & social care | 2017 |
| AL Murphy Limited | Arts & recreation | 2009 |
| AL Spall Financial Services Limited | Financial services | 2015 |
| AL Volo Ltd | Hospitality | 2022 |
| AL Wright Ltd | Manufacturing | 2008 |
| Alamo Energy Ltd | Professional & scientific | 2025 |
| Alamo Projects Limited | Professional & scientific | 2019 |
| Alan G Henderson Limited | Health & social care | 2009 |
| Alan Turner Motors Limited | Wholesale & retail | 2011 |
| Alan Wrigley Associates Limited | Professional & scientific | 1999 |
| Alarmbuild Limited | Financial services | 2002 |
| Alastair Elgey Limited | Administrative & support | 2020 |
| Alato Ltd | Hospitality | 2025 |
| Albany House Management Company (York) Limited | Real estate | 2001 |
| Albemarle Properties (York) Ltd | Real estate | 2021 |
| Albert Hall (Farms) Limited | Agriculture & fishing | 2008 |
| Alcarus Risk Solutions Ltd | Professional & scientific | 2025 |
| Alchemy Enterprise Group Ltd | Administrative & support | 2020 |
| Alchemy Sales & Marketing Limited | Professional & scientific | 2004 |
| Alcuin Homes (Bradford) Limited | Construction | 2015 |
| Alcuin Homes (Flawith) Limited | Construction | 2017 |
| Alcuin Homes (York) Limited | Construction | 2017 |
| Alcuin Homes (Yorkshire) Holdings Limited | Extraterritorial | 2015 |
| Alcuin Homes (Yorkshire) Limited | Construction | 2013 |
| Alcuin Investment Intelligence Limited | Information & communication | 2019 |
| Aldborough Energy Supplies Limited | Manufacturing | 2014 |
| Alderbridge Consulting Limited | Administrative & support | 1997 |
| Alderford Limited | Construction | 2026 |
| Alderman Park (Hasland) Management Company Limited | Households | 2019 |
| Alderson Financial Consultancy Ltd | Professional & scientific | 2023 |
| Alderson Motors Ltd | Wholesale & retail | 2025 |
| Aldersyde Court Limited | Households | 1965 |
| Aldersyde House Management Company Limited | Real estate | 2005 |
| Alderwood Properties Limited | Real estate | 1989 |
| Aldwalk Mews Ltd | Real estate | 2024 |
| Aldwark Bridge Café Ltd | Hospitality | 2020 |
| Aldwark Consulting Limited | Professional & scientific | 2026 |
| Aldwark Management Company Limited | Real estate | 1979 |
| Aldwark Property Company Limited | Construction | 1987 |
| Alea Solutions Ltd | Professional & scientific | 2024 |
| Alegra Strategic Limited | Financial services | 2020 |
| Aleka Limited | Real estate | 2007 |
| Alex Arundel Studio Ltd | Professional & scientific | 2026 |
| Alex James Hunt Ltd | Manufacturing | 2023 |
| Alex Quigley Consultancy Limited | Education | 2018 |
| Alex Roldan Photography Ltd | Professional & scientific | 2018 |
| Alexa Design Limited | Professional & scientific | 2023 |
| Alexa Wilkinson Ltd | Professional & scientific | 2024 |
| Alexander's Cars Ltd | Wholesale & retail | 2026 |
| Alexanders (Boroughbridge) Properties Limited | Real estate | 2010 |
| Alexanders Horseboxes Limited | Administrative & support | 2018 |
| Alex’S Motors Limited | Wholesale & retail | 2023 |
| Alfol Limited | Information & communication | 2000 |
| Alfold Veterinary Practice Limited | Professional & scientific | 2013 |
| Alford Brothers Limited | Professional & scientific | 1954 |
| Alfreds Future Ltd | Professional & scientific | 2025 |
| Alfresco Canopies Limited | Construction | 2019 |
| Alfreton Batley Limited | Administrative & support | 2015 |
| Algometrics Ltd | Other services | 2025 |
| ALH Builders Ltd | Construction | 2012 |
| ALH Property Group Ltd | Real estate | 2025 |
| ALI Barber Limited | Other services | 2012 |
| Alibiltoncooks Limited | Manufacturing | 2019 |
| Alice Hawthorn LLP | | 2014 |
| Alice(Uk) Limited | Construction | 2019 |
| Align & ACT Consultants Ltd | Professional & scientific | 2025 |
| Alin Albu Signalling Consultancy Ltd | Construction | 2022 |
| Alinkah Ltd | Information & communication | 2026 |
| Alisier Associates Ltd | Professional & scientific | 2019 |
| Alison L Clayton Ltd | Professional & scientific | 2012 |
| Alistair Griffin Limited | Information & communication | 2012 |
| Alistair James London Ltd | Extraterritorial | 2016 |
| Alistair W Baldwin Associates Limited | Professional & scientific | 2010 |
| Alixar Limited | Information & communication | 2003 |
| ALJ Engineering Limited | Professional & scientific | 2017 |