| 100% Salons Ltd | Wholesale & retail | 2013 |
| 24-7 Drains Limited | Other services | 2002 |
| 295 Labs Ltd | Information & communication | 2019 |
| 2CS Construction Ltd | Construction | 2014 |
| 2GETHER Bathrooms Ltd | Construction | 2021 |
| 2M Partners Ltd | Hospitality | 2005 |
| 32 Lord Street Gainsborough Ltd | Construction | 2025 |
| 365 Vehicle Logistics Limited | Extraterritorial | 2016 |
| 3CLICKZ Limited | Information & communication | 2024 |
| 3JX Consulting Ltd | Information & communication | 2012 |
| 3JX D365 Assistance Ltd | Information & communication | 2026 |
| 4BEES Maritime Consultancy Ltd | Transport & logistics | 2025 |
| 4POCKETS Limited | Information & communication | 2020 |
| 567 Properties Limited | Real estate | 2020 |
| 6 C'S Mechanical Services Limited | Construction | 2012 |
| 77 Ryland Road Management Company Limited | Construction | 2026 |
| A & J Affordable Housing Ltd | Real estate | 2025 |
| A & J HSE Solutions Ltd | Mining & quarrying | 2023 |
| A B Spirits Limited | Wholesale & retail | 2010 |
| A Dearden (Farming) Limited | Agriculture & fishing | 2002 |
| A Different Angle Ltd | Other services | 2013 |
| A E Wilson & Sons Limited | Transport & logistics | 2010 |
| A J Automobile Ltd | Wholesale & retail | 2025 |
| A J Douce Roofing Ltd | Construction | 2023 |
| A N E Tree Services Ltd | Administrative & support | 2026 |
| A Nicoll & SON Limited | Administrative & support | 1999 |
| A Price Developments Ltd | Real estate | 2019 |
| A Price Electrical Ltd | Construction | 2015 |
| A R Domestic Services Limited | Administrative & support | 2020 |
| A R Peach Services Limited | Transport & logistics | 2014 |
| A Smythe Tsco Services Ltd | Public administration | 2024 |
| A-Z Ecoshine Ltd | Administrative & support | 2025 |
| A. Schulman Gainsborough Ltd | Manufacturing | 1996 |
| A.M. Packaging Limited | Manufacturing | 1980 |
| A.M.P Automation Ltd | Manufacturing | 2019 |
| A.R.S.Recruitment Limited | Administrative & support | 2025 |
| AA Hot TUB Hire Ltd | Administrative & support | 2014 |
| AA Hot Tubs Limited | Wholesale & retail | 2020 |
| AAA English Tuition Ltd | Education | 2020 |
| AAA Firststep Properties Limited | Real estate | 2020 |
| AAB Trades Limited | Real estate | 2014 |
| Aarti Crafty Gifts Limited | Wholesale & retail | 2020 |
| ABD Integrated Consulting Ltd | Professional & scientific | 2024 |
| Abgw Property Holdings Ltd | Real estate | 2024 |
| Abidot Enterprises Ltd | Wholesale & retail | 2025 |
| ABM Electrical Maintenance Ltd | Construction | 2018 |
| AC Air Conditioning by a. Chappelow Ltd | Real estate | 2021 |
| AC Family Office Limited | Financial services | 2020 |
| AC Heating Care Ltd | Construction | 2026 |
| Acis Communities Limited | Financial services | 2024 |
| Acis Development Services Limited | Construction | 2010 |
| Acis Group Limited | Real estate | 1998 |
| Acis Homeplus Limited | Extraterritorial | 2010 |
| Acis Management Limited | Extraterritorial | 2000 |
| Acis Properties Limited | Extraterritorial | 2000 |
| Across the Wash Limited | Real estate | 2019 |
| Actual Potential Ltd | Health & social care | 2026 |
| Acuity Accountants Limited | Professional & scientific | 2019 |
| AD Protective Solutions Ltd | Administrative & support | 2019 |
| Adam Gilbert Developments Ltd | Real estate | 2025 |
| Adam Gilbert Limited | Construction | 2026 |
| Adam Lincoln Ltd | Administrative & support | 2026 |
| Adam Marlow Limited | Wholesale & retail | 2025 |
| Adansonia Confectionery Machinery Sales Limited | Manufacturing | 2020 |
| Adare Homes Ltd | Real estate | 2020 |
| Adbolton Hall Limited | Health & social care | 2009 |
| Adds UP Bookkeeping & Accountancy Services Ltd | Extraterritorial | 2023 |
| Adefess Ventures Ltd | Health & social care | 2019 |
| ADG Railway Ltd | Construction | 2024 |
| ADL Lettings Limited | Real estate | 2011 |
| ADM Agriculture Limited | Wholesale & retail | 1967 |
| Advanced Calibrations Ltd | Wholesale & retail | 2024 |
| Advanced Fitness Careers Limited | Education | 2022 |
| AEA Coaching Ltd | Arts & recreation | 2025 |
| Aegir Digital Ltd | Information & communication | 2014 |
| Aegir Investments Ltd | Real estate | 2021 |
| Aerospray Limited | Construction | 2023 |
| Aesthetics by Carly - Scotter Ltd | Other services | 2024 |
| African Wood Limited | Wholesale & retail | 2025 |
| AG Joinery (Lincs) Ltd | Construction | 2023 |
| Agbupvc Installations Ltd | Construction | 2026 |
| Agst Ltd | Other services | 2020 |
| Ahkcu.Uk Ltd | Wholesale & retail | 2026 |
| Air IP Limited | Professional & scientific | 2024 |
| Aishaa Property Ltd | Real estate | 2024 |
| AIW Construction Limited | Construction | 2025 |
| AJA Construction Ltd | Financial services | 2022 |
| AJA Transport Services Ltd | Transport & logistics | 2018 |
| AJK Digital Media Limited | Wholesale & retail | 2017 |
| Ajwg Limited | Professional & scientific | 2019 |
| AL Sharif Investments Limited | Real estate | 2017 |
| AL Sharif Market Consultants Limited | Real estate | 2014 |
| AL UK Sales Limited | Wholesale & retail | 2022 |
| Alarm Track Ltd | Wholesale & retail | 2025 |
| Alcar Industrial Services Limited | Wholesale & retail | 1983 |
| Alcar International Limited | Manufacturing | 1986 |
| Alcar Precision Products Limited | Manufacturing | 1988 |
| Aldo Green Properties Ltd | Real estate | 2024 |
| Alex B Engineering Limited | Professional & scientific | 2025 |
| Alexander House (1 ST Annes Road) Residents Management Company Limited | Households | 2019 |