| 100 Sports Ltd | Arts & recreation | 2020 |
| 15 Manufacturing Limited | Wholesale & retail | 2012 |
| 192SQFT Goalkeeping Academy UK Ltd | Arts & recreation | 2014 |
| 1AB Properties Ltd | Real estate | 2023 |
| 2 Lebanon Gardens (Wandsworth) Limited | Households | 2021 |
| 333 Enterprises Ltd | Administrative & support | 2019 |
| 365 Consult Ltd | Administrative & support | 2025 |
| 366 Digital Ltd | Information & communication | 2021 |
| 3D Parts Business Ltd | Manufacturing | 2014 |
| 3T Consultancy Limited | Professional & scientific | 2022 |
| 4 YOU ALL Property Limited | Real estate | 2020 |
| 4TH Rock Limited | Information & communication | 2007 |
| 73 REL Developments Limited | Real estate | 2025 |
| @Thepub Ltd | Extraterritorial | 2023 |
| A & K Mycock Limited | Agriculture & fishing | 2026 |
| A J & M E Minshall Limited | Agriculture & fishing | 2008 |
| A J Brewing Ltd | Manufacturing | 2024 |
| A J Thompson Construction Ltd | Construction | 2019 |
| A M Hall Limited | Administrative & support | 1999 |
| A Prime Properties Ltd | Real estate | 2026 |
| A Sims Limited | Agriculture & fishing | 2012 |
| A W Gilman & Sons Limited | Agriculture & fishing | 2002 |
| A. H. Electrical Systems Limited | Construction | 2007 |
| A.C.S Joinery & Building Limited | Construction | 2016 |
| A.T. Richardson & SON Limited | Agriculture & fishing | 1972 |
| Aabickerton Limited | Professional & scientific | 2017 |
| AB Light Rail Solutions Ltd | Professional & scientific | 2026 |
| Abacus Education Consultants Limited | Education | 2015 |
| Aberbraint Ltd | Construction | 2023 |
| Aberdour Medical Limited | Health & social care | 2016 |
| Ace Derbyshire Trust | Education | 2024 |
| Ace Vets Limited | Professional & scientific | 2009 |
| Acres Signs & Graphics Limited | Manufacturing | 2014 |
| Active Apparel Group Limited | Wholesale & retail | 2018 |
| Active Apparel Limited | Wholesale & retail | 2007 |
| Active Lean Solutions Ltd | Professional & scientific | 2006 |
| ACV Engineering Ltd | Manufacturing | 2011 |
| Adam Walkden Limited | Construction | 2014 |
| Adaptavate Innovations Limited | Extraterritorial | 2016 |
| Adept Product Design & Supply Solutions Limited | Professional & scientific | 2025 |
| ADVISORY4PACK Ltd | Administrative & support | 2022 |
| AEA (East Midlands) Ltd | Agriculture & fishing | 2021 |
| Aertec Limited | Transport & logistics | 2013 |
| Afort Services Limited | Professional & scientific | 2024 |
| Aggregate Haulage Limited | Construction | 2017 |
| AHG Design Services Ltd | Professional & scientific | 2020 |
| AHS Consulting Ltd | Professional & scientific | 2021 |
| AIM Sports Group Ltd | Arts & recreation | 2025 |
| Aircooled Accessories Limited | Manufacturing | 2019 |
| AJR Legal Services Limited | Professional & scientific | 2020 |
| Akkurt Bookkeeping Ltd | Professional & scientific | 2020 |
| Alan Bailey Groundworks Limited | Construction | 2004 |
| Alan Brown Surfacing Limited | Construction | 2006 |
| Alastair COX Associates Limited | Administrative & support | 2014 |
| Albany Fabrications Ltd | Manufacturing | 2018 |
| Alertive Limited | Information & communication | 1995 |
| Aligned Excellence Limited | Professional & scientific | 2024 |
| Alison Cook Limited | Other services | 2004 |
| Alison Gregory Wealth Management Limited | Financial services | 2014 |
| Alison Park Management Company Limited | Households | 2024 |
| ALL British Precision Ltd | Manufacturing | 2012 |
| ALL Mower Parts Holdings Ltd | Financial services | 2024 |
| ALL Mower Parts UK Ltd | Wholesale & retail | 2020 |
| ALL Peak Safety Limited | Professional & scientific | 2017 |
| Allen & Wayne Limited | Agriculture & fishing | 2026 |
| Alligator Solutions Ltd | Information & communication | 2023 |
| Allsop Domestic Appliance Sales Ltd | Wholesale & retail | 2002 |
| Allsop Electrical Ltd | Extraterritorial | 2002 |
| Alluminio Designs Ltd | Wholesale & retail | 2022 |
| Alsop Farm Limited | Administrative & support | 2008 |
| Amadeus (UK) Ltd | Professional & scientific | 2023 |
| Amat Limited | Professional & scientific | 2007 |
| Amba Living Limited | Wholesale & retail | 2001 |
| Amber Home Heating Limited | Construction | 2005 |
| Amin J Consulting Ltd | Professional & scientific | 2015 |
| AMJ Futures Ltd | Construction | 2025 |
| Amos Consultancy (Number 1) Limited | Professional & scientific | 2021 |
| Amos Consultancy Ltd | Professional & scientific | 2012 |
| Amos Estates Ltd | Construction | 2013 |
| Amos Farms (Original) Limited | Agriculture & fishing | 2018 |
| Amos Farms Limited | Agriculture & fishing | 2022 |
| Amos Group Limited | Construction | 2005 |
| Amos Holiday Homes Limited | Hospitality | 2026 |
| Amos Homes (Buxton) Ltd | Construction | 2015 |
| Amos Homes (Hartington) Ltd | Financial services | 2017 |
| Amos Homes (Residential) Ltd | Administrative & support | 2017 |
| Amos Homes (Uttoxeter) Ltd | Administrative & support | 2017 |
| Amos Homes Anglesey Number 2 Limited | Real estate | 2022 |
| Amos Homes Group Ltd | Construction | 2015 |
| Amos Homes Limited | Real estate | 2007 |
| Amos Leisure (Ramshorn) Ltd | Hospitality | 2015 |
| AMT Civil Engineering Limited | Construction | 2020 |
| AMY Hope-Smith Limited | Financial services | 2016 |
| Anacre Cakes & Bakes Ltd | Manufacturing | 2024 |
| Anchor Court (Blackburn) Management Company Limited | Real estate | 2007 |
| Andrew Jigson Ltd | Wholesale & retail | 2020 |
| Andy Buckley Angling Services Ltd | Agriculture & fishing | 2022 |
| Anglosaf Limited | Professional & scientific | 2016 |
| Animal Welfare Training Ltd | Professional & scientific | 2000 |
| Antiquaires Ltd | Wholesale & retail | 2013 |