| Astros Kitchen Limited | Hospitality | 2026 |
| Atad Associates Technical and Design Ltd | Information & communication | 2019 |
| ATB by MELBE-1 Limited | Wholesale & retail | 2024 |
| ATB by MELBE-2 Limited | Wholesale & retail | 2024 |
| ATB by MELBE-3 Limited | Wholesale & retail | 2024 |
| ATB by MELBE-4 Limited | Wholesale & retail | 2024 |
| ATB by MELBE-5 Limited | Wholesale & retail | 2024 |
| ATB by MELBE-6 Limited | Wholesale & retail | 2024 |
| ATB by MELBE-7 Limited | Wholesale & retail | 2024 |
| ATB by MELBE-8 Limited | Wholesale & retail | 2024 |
| Atkins Sales Limited | Professional & scientific | 2025 |
| Atlas Chiropractic Ltd | Health & social care | 2017 |
| Atomiq Tech Ltd | Administrative & support | 2024 |
| Attentives Marketing Materials Limited | Professional & scientific | 2021 |
| Audit Bureau of Circulations Limited | Other services | 1931 |
| Auld Orthopaedics Limited | Health & social care | 2011 |
| Aura Education Services Ltd | Administrative & support | 2023 |
| Austins LLP | | 2006 |
| Authentic Experiences Limited | Administrative & support | 2016 |
| Authentic France Limited | Real estate | 2017 |
| Authentic Management Limited | Professional & scientific | 2016 |
| Authentic Wine Limited | Other services | 2020 |
| Authorised Designs Limited | Professional & scientific | 2011 |
| Autoflow Software Ltd | Information & communication | 2026 |
| Autumn Frameworks Limited | Manufacturing | 2013 |
| Avenues Holdings Limited | Financial services | 2024 |
| Averma Consulting Limited | Information & communication | 2008 |
| Avery Magnay Estates Limited | Construction | 1993 |
| Aviary Insights Limited | Professional & scientific | 2026 |
| AVS FIM Limited | Financial services | 2023 |
| Awesome Engineers Ltd | Education | 2014 |
| Awsbot Ltd | Information & communication | 2013 |
| Axamy Ltd | Administrative & support | 2024 |
| Axis Advisors Ltd | Administrative & support | 2025 |
| AXL Business Consultancy Ltd | Administrative & support | 2020 |
| Azille House Ltd | Hospitality | 2003 |
| Aztec Retreats Limited | Administrative & support | 2011 |
| B & H Autos Ltd | Wholesale & retail | 2014 |
| B & H Distribution Limited | Wholesale & retail | 1990 |
| B2 Clinic Holdings Ltd | Real estate | 2026 |
| B2 Group Ltd | Health & social care | 2022 |
| B2 Wendover Clinic Ltd | Health & social care | 2024 |
| B2: Chalfont Clinic Ltd | Health & social care | 2012 |
| B2: Clinic Property Ltd. | Real estate | 2017 |
| Babble Limited | Administrative & support | 2010 |
| Bagshaw & Hardy Limited | Professional & scientific | 2013 |
| Baker Digital Consultancy Limited | Professional & scientific | 2020 |
| Balan HGV Delivery Ltd | Transport & logistics | 2016 |
| Ballards ROW Ltd | Real estate | 2026 |
| BAP Healthcare Ltd | Health & social care | 2021 |
| Baps & Tatties Ltd | Hospitality | 2025 |
| Barcode Technologies Ltd. | Information & communication | 1994 |
| Barker and SON Construction Limited | Construction | 2025 |
| Barknbond Limited | Other services | 2023 |
| Barmik Limited | Professional & scientific | 2009 |
| Barn END Property Limited | Administrative & support | 2017 |
| Barrik Ltd | Information & communication | 2026 |
| Barrus Consultancy Group Limited | Administrative & support | 2021 |
| Barry Wicks Associates Limited | Professional & scientific | 2025 |
| Basegrowth.Io Ltd | Professional & scientific | 2026 |
| Baton Software Ltd | Information & communication | 2025 |
| Bayridge Group Ltd | Professional & scientific | 2018 |
| Bayswood Boarding Cattery Limited | Professional & scientific | 1981 |
| Bayview 2019 Limited | Real estate | 2019 |
| BCC Management Limited | Arts & recreation | 2015 |
| Beat the Odds Foundation Ltd | Education | 2019 |
| Beauty at Number 1 Limited | Other services | 2016 |
| BED Slats Ltd | Manufacturing | 2017 |
| Beespoke Beekeeping Ltd | Agriculture & fishing | 2024 |
| Bell & Maywood Ltd | Extraterritorial | 2014 |
| Bella Grace Property Ltd | Real estate | 2024 |
| Bella Hair Limited | Other services | 2014 |
| Bellamax Ltd | Real estate | 2023 |
| Bellows Consulting Limited | Administrative & support | 2017 |
| Belsfield LLP | | 2012 |
| BEN Kent Consulting Limited | Professional & scientific | 2021 |
| BEN Morton Leadership Ltd | Information & communication | 2013 |
| Benjamin & Associates Limited | Administrative & support | 2018 |
| Benslow Care Homes Limited | Extraterritorial | 2010 |
| Benslow Management Company Limited | Health & social care | 1998 |
| Benslow Property Limited | Health & social care | 2018 |
| Bergin and Bath Limited | Information & communication | 2015 |
| Bergo Group Ltd | Information & communication | 2022 |
| Berkhamdead Limited | Information & communication | 2023 |
| Berkhamsted Airport Taxi Ltd | Transport & logistics | 2025 |
| Berkhamsted and Hemel Hempstead Hockey Club Limited | Arts & recreation | 2018 |
| Berkhamsted Athletic Football Club Ltd | Education | 2024 |
| Berkhamsted Beer Festival CIC | Arts & recreation | 2025 |
| Berkhamsted Body Shop Limited | Wholesale & retail | 2017 |
| Berkhamsted Building Solutions Limited | Construction | 2021 |
| Berkhamsted Building Solutions South Ltd | Construction | 2024 |
| Berkhamsted Business Centre Ltd | Administrative & support | 2017 |
| Berkhamsted Day Nursery Limited | Education | 2011 |
| Berkhamsted Executive Cars Limited | Transport & logistics | 2018 |
| Berkhamsted Foot Clinic Ltd | Health & social care | 2017 |
| Berkhamsted Football Club Limited | Arts & recreation | 2009 |
| Berkhamsted Garage Ltd | Wholesale & retail | 2026 |
| Berkhamsted Garden Services Ltd | Manufacturing | 2016 |
| Berkhamsted Golf Club Limited | Arts & recreation | 2019 |
| Berkhamsted Golf Range Ltd | Arts & recreation | 2024 |