| 'Bigloc Films' Ltd | Information & communication | 2015 |
| 01442MAINTENANCE Limited | Construction | 2013 |
| 11 and 12 Mallow Street Limited | Households | 2018 |
| 110 Shirland Limited | Construction | 2022 |
| 123 Garden Ltd | Households | 2021 |
| 145 Belswains Lane Management Company Limited | Real estate | 2015 |
| 15/09 Power Engineering Limited | Construction | 2005 |
| 16C North Road Limited | Real estate | 2023 |
| 17 Claverton Street Ltd | Households | 2024 |
| 195 High Street (Berkhamsted) Residents Management Company Limited | Households | 2014 |
| 20 Moring Road Management Company Limited | Households | 1995 |
| 26UAR Limited | Other services | 2018 |
| 271 Valley Road RTM Company Ltd | Households | 2017 |
| 2A Talent Solutions Ltd | Administrative & support | 2025 |
| 2TWENTY2 Associates Ltd | Professional & scientific | 2017 |
| 2WD Limited | Professional & scientific | 2025 |
| 3AM Ideas Ltd | Professional & scientific | 2009 |
| 3AM Thoughts Ltd | Professional & scientific | 2025 |
| 3RIBE Media Limited | Information & communication | 2017 |
| 41 SBR Limited | Households | 2013 |
| 7 Holmesdale Road Freehold Company Limited | Households | 2011 |
| 9 Torrington Road Freehold Limited | Households | 2022 |
| 92 Barnsbury Road Limited | Households | 2020 |
| 92 Lady Margaret Road Limited | Households | 1998 |
| A & G Property Developers Limited | Real estate | 2006 |
| A B a Design Associates Limited | Professional & scientific | 2001 |
| A J Webb Energy Consultancy Ltd | Professional & scientific | 2024 |
| A M Roofing & Services Ltd | Construction | 2021 |
| A Magic Place Ltd | Arts & recreation | 2020 |
| A R Batchelor [Plant Hire] Limited | Administrative & support | 2013 |
| A S Treasury Consultancy Ltd | Professional & scientific | 2023 |
| A Sherling Limited | Professional & scientific | 2023 |
| A W Campbell Limited | Administrative & support | 2025 |
| A. F. Green Factors Limited | Information & communication | 2000 |
| A.W.E.S. Limited | Professional & scientific | 2000 |
| Aaron Developments Limited | Construction | 2018 |
| Aaron Scaffolding (Berkhamsted) Limited | Construction | 2017 |
| Abigail Heinimann Ltd | Professional & scientific | 2020 |
| Abikad Ltd | Professional & scientific | 2024 |
| About YOU Media Ltd | Information & communication | 2023 |
| Above IT Limited | Information & communication | 2017 |
| Above Property Ltd | Real estate | 2025 |
| Abrr Investments Limited | Financial services | 2021 |
| Absolute IT Solutions Ltd | Information & communication | 2010 |
| Acacias Capital Ltd | Real estate | 2017 |
| Access Industries Group Limited | Professional & scientific | 1995 |
| Accessible Waterways Association CIC | Other services | 2023 |
| Accountant Berkhamsted Limited | Extraterritorial | 2022 |
| Aclass Tailoring Berko Ltd | Other services | 2020 |
| Acmg Properties Limited | Agriculture & fishing | 2020 |
| Acrobat Productions Limited | Arts & recreation | 2004 |
| ACS Industrial Limited | Administrative & support | 2003 |
| Active NON Executive Services Limited | Professional & scientific | 2005 |
| Active Roofing and Property Maintenance Ltd | Construction | 2023 |
| ADA Architects Ltd | Professional & scientific | 2012 |
| Adcopia Ltd | Administrative & support | 2024 |
| ADF Recruitment Ltd | Administrative & support | 2024 |
| ADL South East Limited | Administrative & support | 2016 |
| ADL Translations Ltd | Professional & scientific | 2021 |
| ADU Design Ltd | Manufacturing | 2019 |
| Advance Event Support Ltd | Administrative & support | 2012 |
| Advanced Development Environments Ltd | Real estate | 1988 |
| Aedificia Limited | Construction | 2026 |
| Aeris Smart Energy Group Limited | Information & communication | 2025 |
| Aether Financial Recruitment Limited | Administrative & support | 2017 |
| Affinity Edge Consulting Limited | Professional & scientific | 2024 |
| Agile Talent Limited | Professional & scientific | 2023 |
| AGP Global Holding Ltd | Wholesale & retail | 2024 |
| AH Pharma Recruiters Ltd | Administrative & support | 2025 |
| AHJ Smile Ltd | Health & social care | 2025 |
| Ahrel & Co Ltd | Professional & scientific | 2019 |
| AI Fertility Ltd | Other services | 2022 |
| AI Tips for Real Life Ltd | Wholesale & retail | 2025 |
| Air 2 Air Limited | Extraterritorial | 2004 |
| Aircraft Engine Management Group Limited | Manufacturing | 2024 |
| Airora Limited | Professional & scientific | 2025 |
| Ajax Commerce Ltd | Wholesale & retail | 2020 |
| AJJ Express Limited | Wholesale & retail | 2024 |
| AJP Trading Services Ltd | Professional & scientific | 2020 |
| Akeman Residential Limited | Real estate | 2023 |
| Akira Enterprise Limited | Professional & scientific | 2025 |
| Alan J Murray Limited | Information & communication | 2011 |
| Alchemy & I (IP) Ltd | Professional & scientific | 2024 |
| Alchemy & I Collective Ltd | Other services | 1994 |
| Alchemy & I Group Limited | Other services | 2022 |
| Alchemy & I Limited | Other services | 2018 |
| Alegria Counselling Ltd | Extraterritorial | 2024 |
| Alegria Wellbeing Services Ltd | Extraterritorial | 2024 |
| Alexander Lewis Investments Ltd | Real estate | 2026 |
| ALH Little Gaddesden Limited | Wholesale & retail | 2023 |
| Alistair Warrell Limited | Professional & scientific | 2022 |
| ALL About Business Limited | Professional & scientific | 2003 |
| ALL Renovations & Refurbishments (AR & R) Ltd | Construction | 2005 |
| ALL Square Recruitment Limited | Administrative & support | 2023 |
| ALL Things Print Studio Limited | Administrative & support | 2023 |
| Allazo Accounting Ltd | Professional & scientific | 2014 |
| Allazo FX Ltd | Administrative & support | 2023 |
| Allazo Investments Ltd | Real estate | 2018 |
| Allazo Ltd | Professional & scientific | 2012 |
| Allgo Construction Services Ltd | Construction | 2020 |