| 1855 Limited | Wholesale & retail | 2022 |
| 345 Event Services Limited | Professional & scientific | 2021 |
| 8&9 Lyons Walk Ltd | Real estate | 2017 |
| A & K Autos Limited | Wholesale & retail | 2001 |
| A & K Read Limited | Wholesale & retail | 2012 |
| A C Stonebridge & Co Limited | Administrative & support | 2021 |
| A Culture of Kindness Ltd | Professional & scientific | 2023 |
| A J N Electrical (Dorset) Limited | Construction | 2002 |
| A K Hosie & Sons Limited | Agriculture & fishing | 2011 |
| A M Donnelly Electrical Contractor Limited | Construction | 2002 |
| A V C Shinebright Ltd | Administrative & support | 2004 |
| A&H Kitchens and Bedrooms Ltd | Construction | 2019 |
| A. Hammond & Sons Limited | Construction | 1959 |
| Abbey RP Ltd | Construction | 2004 |
| Abbeyfield Mews Limited | Households | 2003 |
| Abby Bunyard Farrier & Forge Limited | Other services | 2012 |
| Abicus Accountancy Ltd | Professional & scientific | 2020 |
| Accountancy Plus (Dorset) Limited | Professional & scientific | 2002 |
| Ackerley Properties Ltd | Construction | 2023 |
| AD Phillips Limited | Construction | 2002 |
| Adem Hand Car Wash Limited | Administrative & support | 2026 |
| Adnet Limited | Real estate | 2025 |
| Adrian Moore Limited | Construction | 2006 |
| Advantage Helicopters Ltd | Transport & logistics | 2019 |
| Advisair Limited | Professional & scientific | 2010 |
| Aedre TEC Ltd | Professional & scientific | 2014 |
| Affordable Drainage Ltd | Water & waste | 2026 |
| Agri Essentials Ltd | Wholesale & retail | 2023 |
| AJC Accountancy Limited | Professional & scientific | 2006 |
| AK & AD Parker Limited | Agriculture & fishing | 2005 |
| Alan Garrett Limited | Agriculture & fishing | 2006 |
| Alex Craig Design Limited | Information & communication | 2015 |
| ALL Investments Limited | Real estate | 2022 |
| Amber Pepper Limited | Wholesale & retail | 2023 |
| Ambient Temperature GAS Ltd | Construction | 2014 |
| Andaura Properties Limited | Real estate | 2024 |
| Andrew Lodge Maintenance Ltd | Households | 2019 |
| Anglo French Properties Limited | Real estate | 1987 |
| Anglo French Properties Sales Limited | Real estate | 2026 |
| Apex Carpentry & Developments Ltd | Construction | 2025 |
| APH Classic Car Restoration Limited | Wholesale & retail | 2017 |
| AQL2 Ltd | Professional & scientific | 2026 |
| Aqualux Management Ltd | Manufacturing | 2023 |
| Architectural Plaster Mouldings Limited | Construction | 2012 |
| Article Consultancy Ltd | Manufacturing | 2015 |
| ASH END Enterprises Ltd | Hospitality | 2024 |
| ATT Builders Limited | Construction | 2002 |
| Aurora Care AL Ltd | Health & social care | 2025 |
| Aurora Studios Ltd | Manufacturing | 2013 |
| Aviation Security Limited | Administrative & support | 1989 |
| Away Storage Limited | Transport & logistics | 2017 |
| AYRES501 Ltd | Wholesale & retail | 2025 |
| AZO Equipment Ltd | Manufacturing | 2010 |
| B H Stretton Limited | Agriculture & fishing | 2011 |
| B2B Better Limited | Professional & scientific | 2022 |
| Bale IT Services Limited | Information & communication | 2006 |
| Barbados Dream (Dorset) Ltd | Real estate | 2024 |
| Barber Films Limited | Information & communication | 2012 |
| Barkerstourton Property Search Limited | Other services | 2011 |
| Barlow Electrical (Dorset) Ltd | Construction | 2025 |
| Barry JEX Limited | Construction | 2002 |
| Barwick Building Services Limited | Construction | 2003 |
| Basil Consulting (UK) Limited | Information & communication | 1998 |
| Bath Global Limited | Professional & scientific | 2006 |
| Bdistinctive Limited | Professional & scientific | 1975 |
| Bearfoot Productions Ltd | Administrative & support | 2019 |
| Benkierin Limited | Professional & scientific | 2014 |
| Benville Properties Limited | Extraterritorial | 2004 |
| Bert-Brain Engineering Ltd | Information & communication | 2023 |
| Bespoke Furniture Works Limited | Manufacturing | 2016 |
| Best Print (UK) Ltd | Manufacturing | 1999 |
| Betsy DE Thierry Limited | Health & social care | 2014 |
| Beyond Design Limited | Agriculture & fishing | 1993 |
| Beyond the Spark Limited | Professional & scientific | 2018 |
| Big Old (Wessex) Limited | Real estate | 2016 |
| Biggi Music Ltd | Information & communication | 2008 |
| Biofriendly Europe Limited | Administrative & support | 2009 |
| Black & White IT Ltd | Information & communication | 2011 |
| Blast OFF Events Ltd | Arts & recreation | 2016 |
| BOB Jones Heating Engineer Limited | Construction | 2002 |
| Botanical Enterprises Limited | Wholesale & retail | 2008 |
| Bowland Renewable Systems Ltd | Professional & scientific | 2025 |
| Bramall Gardens Limited | Other services | 2003 |
| Bramshaw Ltd | Real estate | 2018 |
| Bright Building Services Limited | Construction | 2006 |
| Bruce Rooms Ltd | Real estate | 2021 |
| BSU Services Limited | Wholesale & retail | 2025 |
| Budgetwise Ltd | Information & communication | 2023 |
| Buffets Close Property Management Limited | Administrative & support | 2000 |
| Bulmag Ltd | Wholesale & retail | 2019 |
| Burden Transport Limited | Transport & logistics | 1996 |
| Buzz Kill Productions Limited | Information & communication | 2015 |
| Bywyd Ltd | Professional & scientific | 2024 |
| C & S Meats Limited | Manufacturing | 2002 |
| C R Groundcare Limited | Administrative & support | 2010 |
| C.C.Moore & Co Limited | Manufacturing | 1958 |
| Calderpink Ltd | Administrative & support | 2009 |
| Caleva Process Solutions Ltd. | Manufacturing | 1995 |
| Callaways Leisure Ltd | Wholesale & retail | 2026 |
| Camborne Insurance Services Ltd. | Real estate | 1977 |