| Allenton Fish and Chips Limited | Hospitality | 2026 |
| Allenton Kebabs Ltd. | Hospitality | 2018 |
| Allenton Local Mini Market Limited | Wholesale & retail | 2025 |
| Allereso Limited | Financial services | 2023 |
| Allerton Gate Management Company Limited | Households | 2025 |
| Allestree B&L Ltd | Construction | 2023 |
| Allestree Domestic Services Limited | Other services | 2012 |
| Allestree Ecom Ltd | Wholesale & retail | 2025 |
| Allestree Engineering Ltd | Professional & scientific | 2012 |
| Allestree Groundworks Limited | Construction | 2008 |
| Allestree Health & Homecare Services Limited | Other services | 2012 |
| Allestree Property Developers Ltd | Construction | 2019 |
| Allestree Stores Limited | Wholesale & retail | 2021 |
| Allestree Woodlands School | Education | 2012 |
| Allgas (Derby) Limited | Other services | 2006 |
| Alliance for Access Limited | Education | 2020 |
| Alliance Guarding Services Limited | Administrative & support | 2022 |
| Alliance Vehicle Hire Ltd | Transport & logistics | 2026 |
| Allied Legal Services Limited | Professional & scientific | 2017 |
| Allies for Inclusion Ltd | Education | 2022 |
| Allies Property Group Ltd | Real estate | 2025 |
| Alloy Stock Limited | Wholesale & retail | 1994 |
| ALLPROP360 Garden Care Ltd | Administrative & support | 2024 |
| Allsop Properties Limited | Real estate | 1999 |
| Allsop Property Holdings Limited | Financial services | 2023 |
| Allsopp IT Services Ltd | Information & communication | 2024 |
| Allsuns Electrical Limited | Construction | 2007 |
| Alltime 1STCLASS Care Ltd | Health & social care | 2020 |
| Allumy Motorsport Limited | Wholesale & retail | 2014 |
| Allure Living Ltd | Real estate | 2018 |
| Alluretrendz Limited | Wholesale & retail | 2024 |
| Allways Forktruck Services Limited | Manufacturing | 1997 |
| Allwayssupply Ltd | Wholesale & retail | 2025 |
| Allwyn Windows Ltd | Construction | 2009 |
| Ally Moore Coaching & Culture Ltd | Professional & scientific | 2021 |
| Allyear Healthcaring Solutions Ltd | Public administration | 2024 |
| Alma Capital Invest Ltd | Real estate | 2025 |
| Alma Homes Ltd | Real estate | 2023 |
| Almagordo Ltd | Professional & scientific | 2019 |
| Almax Electrical Solutions Ltd | Construction | 2025 |
| Almerimar Business Solutions Limited | Wholesale & retail | 2008 |
| Almerimar Property Solutions Limited | Real estate | 2010 |
| Almett Limited | Construction | 2019 |
| Almostblack Ltd | Transport & logistics | 2026 |
| Almyra Catering Ltd | Hospitality | 2015 |
| Alnoor Shawarma Limited | Hospitality | 2025 |
| Alongside Ltd | Information & communication | 2007 |
| Alonso Close RTM Company Ltd | Real estate | 2013 |
| Alonyx Limited | Information & communication | 2013 |
| Alore Studios Ltd | Professional & scientific | 2025 |
| Alpenvista Ltd | Wholesale & retail | 2025 |
| Alph Limited | Manufacturing | 2015 |
| Alpha 1 Construction Limited | Construction | 2015 |
| Alpha Care Consult Limited | Administrative & support | 2024 |
| Alpha Data Analytics Hub Limited | Information & communication | 2025 |
| Alpha Drain Services Limited | Administrative & support | 1995 |
| Alpha Driveways and Landscapes Limited | Construction | 2022 |
| Alpha Manufacturing Ltd | Professional & scientific | 2011 |
| Alpha Moon Limited | Administrative & support | 2008 |
| Alpha Neuro Massage Ltd | Health & social care | 2024 |
| Alphababa Ltd | Information & communication | 2022 |
| Alphabet Studios Ltd | Manufacturing | 2025 |
| Alphamind Ltd | Information & communication | 2017 |
| Alphatekk Ltd | Information & communication | 2022 |
| Alphaujla Limited | Information & communication | 2021 |
| Alphawolf Software Limited | Information & communication | 2012 |
| Alphine Properties Limited | Real estate | 2004 |
| Alpiaal Services Ltd | Hospitality | 2025 |
| Alpine Accident Claims Limited | Financial services | 2004 |
| Alpine Cooling (UK) Limited | Construction | 2003 |
| Alpine Paving and Landscapes Limited | Administrative & support | 2025 |
| Alpine Red Ltd | Information & communication | 2013 |
| Alport Joinery & Bespoke Cabinetry Ltd | Manufacturing | 2025 |
| Alps Group Limited | Real estate | 2000 |
| Alps International Limited | Professional & scientific | 2001 |
| Alps Projects Limited | Professional & scientific | 2002 |
| Alps Tech Solutions Limited | Professional & scientific | 2012 |
| ALR Consultants Limited | Professional & scientific | 2016 |
| Alrock Mechanical Ltd | Construction | 2017 |
| Alsand Management Limited | Wholesale & retail | 2011 |
| Alsand Properties Limited | Real estate | 2021 |
| Alstom (Investment) UK Limited | Financial services | 2015 |
| Alstom Academy for Rail | Professional & scientific | 1934 |
| Alstom NL Service Provision Ltd | Transport & logistics | 1993 |
| Alstom Product and Services Limited | Manufacturing | 2006 |
| Alstom Transport Service Ltd | Extraterritorial | 1993 |
| Alstom Transport UK (Holdings) Limited | Professional & scientific | 2013 |
| Alstom Transport UK Limited | Manufacturing | 2013 |
| Alstom Transportation (Global Holding) UK Limited | Financial services | 2015 |
| Alstom UK Pension Trustee Limited | Financial services | 2014 |
| Alstom UK VP Pension Trustee Limited | Financial services | 2014 |
| Alstonefield Ltd | Health & social care | 2023 |
| ALT Brickwork Ltd | Construction | 2019 |
| ALT Design Limited | Administrative & support | 2003 |
| Alteracetions Limited | Manufacturing | 2024 |
| Alterares Holdings Ltd | Financial services | 2022 |
| Alternative Tiles Limited | Wholesale & retail | 2007 |
| Althaus Digital Limited | Education | 2009 |
| Althaus Group Limited | Education | 2019 |
| Althaus Talent Limited | Administrative & support | 2022 |