| 0NYX Reelz Ltd | Information & communication | 2026 |
| 1 Plus Management Holdings Limited | Financial services | 2014 |
| 1 Plus Media Group Limited | Professional & scientific | 2009 |
| 1 Plus.Net Limited | Professional & scientific | 2007 |
| 16-23 Broyle Close Limited | Households | 2017 |
| 1708 Consultancy Ltd | Professional & scientific | 2026 |
| 1ST Class Scaffolding (South) Ltd | Construction | 2015 |
| 260 Seafront (Management) Limited | Professional & scientific | 2012 |
| 33 Beach Road Ltd | Households | 2018 |
| 359-369 Wandsworth Road Limited | Real estate | 2014 |
| 3C Business Solutions Limited | Professional & scientific | 2014 |
| 3D Work (Hampshire) Limited | Professional & scientific | 2010 |
| 3TEN Holdings Limited | Administrative & support | 2015 |
| 44 South Terrace (Freehold) Limited | Real estate | 2016 |
| 72 Productions Ltd | Manufacturing | 2024 |
| 7711 Investments Ltd | Real estate | 2021 |
| A & D Lawson Holdings Ltd | Real estate | 2018 |
| A & L Plant Hire Limited | Administrative & support | 2019 |
| A & S Signs & Graphics Ltd | Other services | 2009 |
| A Flame Ltd | Hospitality | 2018 |
| A K Basic Ltd | Wholesale & retail | 2015 |
| A Rhys Consultancy Limited | Professional & scientific | 2022 |
| A Shields Brickwork Ltd | Administrative & support | 2018 |
| A&A Elite Executive Ltd | Transport & logistics | 2026 |
| A-Z Basic Ltd | Wholesale & retail | 2022 |
| A-Z WE Love Gadget Ltd | Wholesale & retail | 2023 |
| A.C. Redman Metal Spinnings Ltd. | Administrative & support | 2004 |
| A.D. Horner Limited | Professional & scientific | 1996 |
| A.M.P Insurance Brokers Limited | Financial services | 2018 |
| A.R.F. Surveying Ltd | Wholesale & retail | 2019 |
| A1 Datanetworks Ltd | Information & communication | 2011 |
| A1 Top Flight Travel Hampshire Limited | Transport & logistics | 2019 |
| Aaliyah Store Ltd | Wholesale & retail | 2026 |
| AAP Couriers Ltd | Transport & logistics | 2025 |
| Aasha (Retail) Ltd | Health & social care | 2003 |
| AB and V Limited | Health & social care | 2014 |
| Abba Housing Limited | Real estate | 2025 |
| Abrico Limited | Hospitality | 2025 |
| AC & RJ Motors Ltd | Wholesale & retail | 2025 |
| Acadia Services Ltd | Administrative & support | 2018 |
| Acbs Care Limited | Other services | 2009 |
| Account Monkey Limited | Professional & scientific | 2023 |
| Accounting for Your Needs Limited | Professional & scientific | 2018 |
| Acorn Engineering Havant Limited | Professional & scientific | 2013 |
| ACR Telecoms Ltd | Information & communication | 2014 |
| ACS Plant & Machinery Sales Ltd | Wholesale & retail | 2010 |
| ADA Homes (Southern) Ltd | Real estate | 2026 |
| Adam Curley Ltd. | Administrative & support | 2011 |
| Adam Mercer Engineering Limited | Manufacturing | 2025 |
| Addison Harper LLP | | 2011 |
| ADL Engineering Limited | Construction | 2005 |
| Advance Insight Ltd | Professional & scientific | 2011 |
| Advanced Gate Solutions Holdings Ltd | Financial services | 2024 |
| Advanced Gate Solutions Limited | Wholesale & retail | 2015 |
| Advanced Thinking Systems Ltd | Information & communication | 1994 |
| Advanced Vehicle Installations Ltd | Wholesale & retail | 2010 |
| Adventure Trader Limited | Wholesale & retail | 2015 |
| Adventure With US Ltd | Arts & recreation | 2021 |
| AEF Property Limited | Real estate | 2025 |
| Aejn Limited | Information & communication | 2019 |
| AFS Marketing Ltd | Professional & scientific | 2022 |
| AGH Drivers Ltd | Wholesale & retail | 2022 |
| Agri Admin Company Limited | Professional & scientific | 2016 |
| Ahmarra Door Installations Limited | Manufacturing | 2007 |
| Ahmarra Door Solutions Limited | Manufacturing | 2007 |
| Ahmarra Installations Ltd | Manufacturing | 2008 |
| Ahmarra Limited | Extraterritorial | 2008 |
| Airgard Systems Limited | Manufacturing | 2020 |
| AJ Decorating & Maintenance Ltd | Administrative & support | 2025 |
| AJ Team Cleaning Ltd | Administrative & support | 2024 |
| AJD Accountancy Limited | Professional & scientific | 2015 |
| AJD Catering Ltd | Hospitality | 2019 |
| Akadata Limited | Wholesale & retail | 2022 |
| Akshar Trading Ltd | Wholesale & retail | 2006 |
| Alexandar G Ltd | Health & social care | 2017 |
| Alexander Hall & Company Limited | Extraterritorial | 2025 |
| Alexandria Park Management Company Limited | Administrative & support | 2014 |
| Alfie's ARC CIC | Hospitality | 2024 |
| Alhambra Court Limited | Real estate | 2002 |
| Alice Fish Bar Ltd | Hospitality | 2017 |
| Aljagail Property Services Limited | Real estate | 2015 |
| ALL About Print Ltd | Professional & scientific | 2018 |
| ALL for Social Ltd | Professional & scientific | 2018 |
| ALL K9 Ladies Ltd | Administrative & support | 2025 |
| Allcool Climate Control Services Limited | Energy | 2007 |
| Alphacars Havant Limited | Transport & logistics | 2019 |
| Alternative Building Services Southern Limited | Construction | 2015 |
| Alva Properties LLP | | 2015 |
| Am-Pm Accounting Solutions Limited | Professional & scientific | 2010 |
| Amaya Sales UK Limited | Manufacturing | 2003 |
| Amb-Decorating Ltd | Construction | 2023 |
| AMY Jones Hair Ltd | Other services | 2021 |
| Ancala Fornia Holdco Limited | Water & waste | 2016 |
| Ancala Fornia Limited | Water & waste | 2016 |
| Ancala Fornia Midco Limited | Water & waste | 2016 |
| Andamar Limited | Construction | 2015 |
| Andover Barbers Ltd | Other services | 2017 |
| Andrew Oliver Shipwrights Limited | Manufacturing | 2016 |
| Anetic AID Limited | Manufacturing | 1977 |
| Angel Radio Limited | Information & communication | 2005 |