| Alfreds Wine Ltd | Hospitality | 2024 |
| Alice Worsdall Consultancy Ltd | Information & communication | 2017 |
| Allwell Developments Ltd | Construction | 2021 |
| Alphi Group Ltd | Information & communication | 2026 |
| ALT Digital Limited | Professional & scientific | 2023 |
| Altogether IT Limited | Information & communication | 2015 |
| Amara Coaching and Training Ltd | Professional & scientific | 2022 |
| AMG Utility Services Ltd | Construction | 2024 |
| Analytics FC Ltd | Information & communication | 2016 |
| Andrew Carpenter Consulting Limited | Professional & scientific | 2012 |
| Andrew Dart Legal Consultant Ltd | Professional & scientific | 2014 |
| Andros UK Limited | Manufacturing | 2008 |
| Angela Murfitt Financial Management Limited | Professional & scientific | 2004 |
| Annika Reed Studio Ltd | Manufacturing | 2026 |
| Anova Enterprises Ltd | Professional & scientific | 2022 |
| Anpier Limited | Wholesale & retail | 2018 |
| Anthony Oram Ltd | Professional & scientific | 2013 |
| Anthony Peverelle Ltd | Wholesale & retail | 2003 |
| Antleaf Ltd. | Information & communication | 2017 |
| Anything Creative Ltd | Arts & recreation | 2015 |
| APC Retail Consultancy Ltd | Professional & scientific | 2020 |
| Aperture Science Ltd | Extraterritorial | 2013 |
| Apex Engineering Limited | Manufacturing | 2004 |
| Apex House Frome Limited | Construction | 2015 |
| Apex Music Ltd | Administrative & support | 2019 |
| APF Enterprises Ltd | Wholesale & retail | 2019 |
| APF Homes Ltd | Real estate | 2021 |
| Aphiwe Health Care Solutions Limited | Health & social care | 2022 |
| ARC House Visuals Ltd | Professional & scientific | 2021 |
| ARC Pilates Limited | Professional & scientific | 2017 |
| Arcane Anthology Studio Ltd | Wholesale & retail | 2023 |
| Armour Heritage Limited | Professional & scientific | 2012 |
| ARN CNC Ltd | Manufacturing | 2020 |
| ARN Design Ltd | Professional & scientific | 2013 |
| Arrett Advisory Ltd | Professional & scientific | 2026 |
| Arrowild Ltd | Wholesale & retail | 2018 |
| Art of a Fine Nature Ltd | Manufacturing | 2022 |
| Art Research Technology Ltd | Professional & scientific | 2023 |
| Artisan Food Club Ltd | Wholesale & retail | 2015 |
| Artisan Food Club Online Limited | Wholesale & retail | 2022 |
| Artsanac Limited | Information & communication | 2015 |
| AS Group Holdings Limited | Financial services | 2020 |
| Ashman Affinity Solutions Ltd | Information & communication | 2021 |
| Ashtree Marine Limited | Information & communication | 2014 |
| ASK Renewables Solutions Limited | Construction | 2026 |
| ASMUND56 Ltd | Information & communication | 2025 |
| Aspect Retail & Media Ltd | Wholesale & retail | 2021 |
| Assured Demolition (South West) Limited | Construction | 2006 |
| Astutum Ltd | Information & communication | 2011 |
| AT the Wilde Table Ltd | Manufacturing | 2008 |
| Attfield Ltd | Professional & scientific | 2015 |
| Atwell Care Limited | Health & social care | 2020 |
| Atyeo Place (Warminster) Management Company Limited | Administrative & support | 2009 |
| Aurora Spa Frome Limited | Other services | 2024 |
| Austin's Contractors Ltd | Construction | 2002 |
| AVB Marine Ltd | Manufacturing | 2022 |
| Aviano Properties Ltd | Wholesale & retail | 2023 |
| Avis Holdings Limited | Financial services | 2024 |
| Avonsdown Properties (Holdings) Limited | Real estate | 2019 |
| Avonsdown Properties Limited | Real estate | 2009 |
| Axton Security & Automation Ltd | Administrative & support | 2023 |
| Ayres GP Limited | Health & social care | 2021 |
| B 5 Limited | Construction | 1990 |
| B Sprake Building Contractor Ltd | Construction | 2018 |
| B.O.A. Accountancy Limited | Professional & scientific | 2008 |
| Baber Plant Hire and Groundworks Limited | Construction | 2001 |
| Back Street Garden CIC | Agriculture & fishing | 2026 |
| Back to Nature CIC | Education | 2023 |
| BAD Arcane Ltd | Wholesale & retail | 2025 |
| Badcox Mini Store Ltd | Wholesale & retail | 2025 |
| Badly-Framed Images Ltd | Information & communication | 2023 |
| Bamapa Clean Ltd | Administrative & support | 2023 |
| Bamba Holdings Limited | Real estate | 2026 |
| Banana Software Systems Limited | Information & communication | 1998 |
| Banks Farm (Chesterblade) Limited | Agriculture & fishing | 1964 |
| Baobab Digital Limited | Professional & scientific | 2016 |
| Bark & Brew Development Ltd | Information & communication | 2025 |
| Barker Bricklayers Ltd | Construction | 2017 |
| Barnaby Pickering Media Ltd | Professional & scientific | 2026 |
| Barnes Coachworks Limited | Wholesale & retail | 1980 |
| Bath & West Mortgages Ltd | Financial services | 2021 |
| Bath Conservation Architects Ltd | Professional & scientific | 2018 |
| Bath General Builders Limited | Construction | 2025 |
| Bath Granite & Marble Limited | Construction | 2001 |
| Bath VW Campers Ltd | Wholesale & retail | 2017 |
| Bathroom Warehouse (Frome) Limited | Wholesale & retail | 2005 |
| Batsford SAW Mills and Timber Limited | Manufacturing | 1997 |
| Batsford Timber Limited | Manufacturing | 1994 |
| Batsrock Financial Ltd | Financial services | 2019 |
| Batsrock Holdings Ltd | Financial services | 2018 |
| BB Sunrise Properties Limited | Real estate | 2015 |
| BE Astute Limited | Professional & scientific | 2018 |
| Beach Education Limited | Education | 2024 |
| Beau Nosh Catering Limited | Hospitality | 1997 |
| Beauty TAN Ltd | Other services | 2015 |
| Beckington Castle Ltd | Real estate | 1989 |
| Beckington Motors Ltd | Wholesale & retail | 2018 |
| Beckley Consultancy Services Ltd | Professional & scientific | 2018 |
| Becoming Properties Ltd | Construction | 2023 |
| Beeching Capital Limited | Financial services | 2017 |