| ADM Software Solutions Ltd | Information & communication | 2013 |
| ADM Surveyors Limited | Professional & scientific | 2009 |
| Admission Master Ltd | Information & communication | 2024 |
| Admo Property Management Limited | Real estate | 2022 |
| ADN Partnership Group Ltd | Financial services | 2026 |
| ADN Pship Holdings Ltd | Financial services | 2026 |
| ADN1 Ltd | Financial services | 2026 |
| Adnan Tahir Joiya Ltd | Wholesale & retail | 2024 |
| Adore Atelier Ltd | Wholesale & retail | 2024 |
| Adore Fine Art Limited | Wholesale & retail | 2019 |
| Adore Fine Homes Limited | Real estate | 2022 |
| Adore Herbal Salon and Spa Ltd | Other services | 2021 |
| Adorn Events Co Ltd | Arts & recreation | 2019 |
| Adorn Packaging Ltd | Administrative & support | 2024 |
| ADP Dental Limited | Health & social care | 2024 |
| Adpsychotherapy Limited | Health & social care | 2021 |
| ADR Capital Ltd | Real estate | 2017 |
| ADR Global Ltd | Hospitality | 2024 |
| ADR Mediation Ltd | Public administration | 2025 |
| Adrc Holding Limited | Financial services | 2026 |
| Adream Ltd | Real estate | 2024 |
| Adrem Enterprises Limited | Professional & scientific | 2006 |
| Adresse Real Estate Ltd | Real estate | 2023 |
| Adria Serenity Ltd | Construction | 2022 |
| Adriamed Ltd | Health & social care | 2020 |
| Adrian HGV Transport Ltd | Transport & logistics | 2025 |
| Adrian Lincan Ltd | Transport & logistics | 2025 |
| Adrian Marriott Limited | Other services | 2008 |
| Adrian Transport Services Ltd | Transport & logistics | 2018 |
| Adrian TV Limited | Transport & logistics | 2013 |
| ADRIAN2014 Ltd | Transport & logistics | 2019 |
| Adroit Limited | Health & social care | 2026 |
| Adroit Precision & General Engineers Limited | Professional & scientific | 1983 |
| ADS Laser Cutting Ltd | Manufacturing | 2005 |
| Adsis IT Limited | Information & communication | 2006 |
| Adsoft Limited | Administrative & support | 2023 |
| Adstrad Ltd | Professional & scientific | 2018 |
| Adsynergy Limited | Professional & scientific | 2010 |
| Aduma’S Beauty Salon Ltd | Other services | 2021 |
| ADV 10 Ltd | Other services | 2019 |
| ADV Stores Ltd | Wholesale & retail | 2025 |
| Adva Structures Ltd | Construction | 2026 |
| Advace Aerospace Innovations Limited | Manufacturing | 2026 |
| Advance Labels Limited | Manufacturing | 2008 |
| Advance Motion Pictures Ltd | Arts & recreation | 2023 |
| Advance Networks Limited | Information & communication | 2003 |
| Advance Office Products Ltd | Manufacturing | 2011 |
| Advance Performance Solutions Ltd | Professional & scientific | 2016 |
| Advance Stairlifts Limited | Wholesale & retail | 2012 |
| Advance Tapes Group Limited | Manufacturing | 1964 |
| Advance Tapes International Limited | Manufacturing | 1968 |
| Advanced Carpentry & Property Solutions Ltd | Manufacturing | 2026 |
| Advanced Carpentry (Leicester) Limited | Construction | 2009 |
| Advanced Carpentry Limited | Manufacturing | 2015 |
| Advanced Eco Services Ltd | Construction | 2024 |
| Advanced Football Development Academy Limited | Education | 2013 |
| Advanced Heating Technologies Ltd | Construction | 2021 |
| Advanced Industrial Maintenance Services Ltd | Manufacturing | 2025 |
| Advanced Laser Clinic Limited | Health & social care | 2021 |
| Advanced Machinery Services Limited | Manufacturing | 2007 |
| Advanced Machining Ltd | Manufacturing | 2015 |
| Advanced Micro Lubrication Limited | Professional & scientific | 1994 |
| Advanced Mortgage Solutions Leicester Ltd | Financial services | 2014 |
| Advanced MSK Ltd | Other services | 2020 |
| Advanced Plumbing (Leicester) Limited | Construction | 2002 |
| Advanced Prosthetics Limited | Health & social care | 2006 |
| Advanced Protective Systems Ltd | Administrative & support | 1996 |
| Advanced Skills Consulting Limited | Professional & scientific | 2025 |
| Advanced Smoke Controls Ltd | Administrative & support | 2015 |
| Advanced Smoke Group Limited | Administrative & support | 2008 |
| Advanced Tax Solutions Ltd | Professional & scientific | 2018 |
| Advanced Therapeutic Materials Limited | Manufacturing | 2003 |
| Advanced Thermal Build Solutions Ltd | Construction | 2015 |
| Advanced Vehicle Systems Ltd | Information & communication | 2020 |
| Advans Cleaning Ltd | Administrative & support | 2024 |
| Advantacare Limited | Health & social care | 2025 |
| Advantage Claims Solutions Corporation Ltd | Information & communication | 2021 |
| Advantage Parts Solutions Ltd | Administrative & support | 1994 |
| Advantus Reports Limited | Other services | 2013 |
| Advay PVT Ltd | Health & social care | 2022 |
| Advce Ltd | Transport & logistics | 2020 |
| Advent Enterprises Limited | Real estate | 2002 |
| Adventure Balloons Limited | Transport & logistics | 2003 |
| Adventurhers C.I.C. | Education | 2025 |
| Advertza Services Ltd | Wholesale & retail | 2025 |
| ADVICE4ACCOUNTS Ltd | Professional & scientific | 2011 |
| ADVICE4TRAINING Centre Limited | Administrative & support | 2019 |
| ADVICE4TRAINING CIC | Education | 2022 |
| Advnc - Tailored Business Solutions Ltd | Professional & scientific | 2017 |
| ADY Beever Consultancy Ltd | Professional & scientific | 2018 |
| ADZ Packaging Ltd | Wholesale & retail | 2025 |
| ADZ Properties Ltd | Real estate | 2017 |
| Adzooze Ltd | Professional & scientific | 2023 |
| Adzy Scaffolding Ltd | Construction | 2025 |
| Adzy's Goods Ltd | Wholesale & retail | 2020 |
| AE Investments Ltd | Real estate | 2021 |
| AEA Property Limited | Real estate | 2026 |
| Aebi Logistics Ltd | Transport & logistics | 2025 |
| Aedis Regulatory Services Group of Companies Ltd | Wholesale & retail | 2018 |
| Aegean AFC Limited | Professional & scientific | 2008 |