| Accurpro Ltd | Professional & scientific | 2025 |
| Acdc Cranes Ltd. | Construction | 2008 |
| Ace 2024 Ltd | Financial services | 2024 |
| Ace Club Sheffield CIC | Health & social care | 2026 |
| Ace Coatings Limited | Wholesale & retail | 2006 |
| Ace Coatings North Limited | Wholesale & retail | 2016 |
| Ace Couriers UK Ltd | Transport & logistics | 2021 |
| Ace Damp Proofing & Plastering Ltd | Construction | 2023 |
| Ace Domestic Appliances Limited | Wholesale & retail | 2017 |
| Ace Education Manchester Community Project CIC | Education | 2024 |
| Ace Electrical Ltd | Construction | 2025 |
| Ace Electrical Solutions Ltd | Construction | 2021 |
| Ace Electrical South Yorkshire Ltd | Construction | 2023 |
| Ace Elevators (Southern) Limited | Other services | 2003 |
| Ace Engineering Designs Ltd | Professional & scientific | 2025 |
| Ace Entertainment Limited | Arts & recreation | 1999 |
| Ace Fabricatons & Installations Ltd | Manufacturing | 2026 |
| Ace Janitorial Supplies Limited | Wholesale & retail | 1974 |
| Ace MAG Limited | Extraterritorial | 2009 |
| Ace Mortgages Limited | Financial services | 2021 |
| Ace Races Ltd | Arts & recreation | 2020 |
| Ace Taxis Sheffield Limited | Transport & logistics | 2020 |
| Aceh Independent Nation CIC | Information & communication | 2025 |
| Acelane Consultancy Limited | Information & communication | 2025 |
| Acentryk Ltd | Wholesale & retail | 2025 |
| Acentus Contracting Ltd | Administrative & support | 2023 |
| Acentus Ltd | Real estate | 2017 |
| Aceprime Consulting Limited | Information & communication | 2025 |
| Acer Mews Health Care Limited | Health & social care | 2023 |
| Acer Shipping Limited | Transport & logistics | 2018 |
| Aceshaw Limited | Real estate | 2022 |
| Acevital Healthcare Ltd | Health & social care | 2024 |
| ACF Ltip Limited | Administrative & support | 2019 |
| Acgcom Ltd | Hospitality | 2018 |
| Achim Trans Ltd | Transport & logistics | 2017 |
| Achu Construction Ltd | Construction | 2020 |
| ACI (Northern) Limited | Administrative & support | 2010 |
| ACI Studios Limited | Professional & scientific | 2025 |
| Acid Bath Publishing Ltd | Information & communication | 2020 |
| Acidhousecoffee Ltd | Hospitality | 2025 |
| Acimovdragan Ltd | Other services | 2023 |
| Acjd Construction Ltd | Construction | 2020 |
| Ackroyd & Abbott Developments Limited | Extraterritorial | 1989 |
| Ackroyd & Abbott Holdings Limited | Extraterritorial | 2017 |
| Ackroyd & Abbott Homes Limited | Extraterritorial | 1938 |
| Ackroyd & Abbott Limited | Construction | 1952 |
| Ackworth Flowers Limited | Wholesale & retail | 2019 |
| ACL Holdco Limited | Financial services | 2023 |
| ACL Propco Limited | Financial services | 2023 |
| ACM Planning Limited | Professional & scientific | 2019 |
| Acme ARB Ltd | Agriculture & fishing | 2015 |
| Acme Compactors Ltd | Manufacturing | 2024 |
| Acme Skips Limited | Water & waste | 2010 |
| ACN Professional Services Ltd | Professional & scientific | 2012 |
| Acorn & Oak Property Ltd | Real estate | 2019 |
| Acorn 2 Oak Ceremonies Ltd | Education | 2023 |
| Acorn Accountancy Services Limited | Professional & scientific | 2023 |
| Acorn Business Solutions Limited | Administrative & support | 2016 |
| Acorn Chorley Limited | Administrative & support | 2013 |
| Acorn Developments Investment Ltd | Other services | 2007 |
| Acorn Horticulture Limited | Wholesale & retail | 2009 |
| Acorn Properties (North) Limited | Construction | 2003 |
| Acorn Reserve Ltd | Financial services | 2021 |
| Acorn Signs (Sedgley) Limited | Professional & scientific | 2001 |
| Acorn Speech Therapy Ltd | Education | 2024 |
| Acornsoft Limited | Information & communication | 2004 |
| Acoustic and Insulation Manufacturing Limited | Extraterritorial | 1986 |
| Acoustic Angels Limited | Administrative & support | 2011 |
| ACP Limited | Real estate | 2019 |
| Acquire Learning College Ltd | Wholesale & retail | 2016 |
| Acquire Properties Ltd | Real estate | 2024 |
| Acquisition Funding Experts UK Ltd | Administrative & support | 2024 |
| Acre XP1 Ltd | Information & communication | 2025 |
| Acres Hill Business Park Management Ltd | Real estate | 2024 |
| Acrestate Limited | Real estate | 1984 |
| Acropolis Limited | Hospitality | 2018 |
| Across 13 Months Ltd | Information & communication | 2023 |
| ACS Estates Limited | Construction | 2010 |
| ACT Building Compliance Ltd | Professional & scientific | 2026 |
| ACT Investment Consulting Ltd | Extraterritorial | 2011 |
| Actacc | Professional & scientific | 2002 |
| Acte Plus UK Ltd | Transport & logistics | 2026 |
| Actio Pauliana Ltd | Professional & scientific | 2010 |
| Action 4 Business Limited | Extraterritorial | 2004 |
| Action Computer Supplies Limited | Professional & scientific | 1990 |
| Action Glass & Heritage Windows Limited | Manufacturing | 2026 |
| Action Limited | Professional & scientific | 1990 |
| Action Trans Ltd | Transport & logistics | 2022 |
| Activ Physiotherapy Ltd | Health & social care | 2012 |
| Active Accommodation Ltd | Health & social care | 2020 |
| Active Chiros Limited | Health & social care | 2006 |
| Active Community Futures CIC | Arts & recreation | 2025 |
| Active Community Trust Ltd | Education | 2008 |
| Active Education Alternative Provision CIC | Education | 2022 |
| Active Education Provision Ltd | Education | 2024 |
| Active Friendly Support Limited | Other services | 2017 |
| Active Healthcare Professionals Limited | Health & social care | 2016 |
| Active Legs Limited | Professional & scientific | 2015 |
| Active Management Services Limited | Other services | 1980 |
| Active Metals Limited | Manufacturing | 1984 |