| BBT Holdings Limited | Households | 2023 |
| BCK Flat Roofing Ltd | Agriculture & fishing | 2018 |
| Bdds Scotland Ltd | Financial services | 2025 |
| BDF Associates Ltd | Other services | 2015 |
| Bearded Barber Ltd | Other services | 2025 |
| Beastie Brews Ltd | Hospitality | 2025 |
| Beatbox Leisure Group Ltd | Arts & recreation | 2023 |
| Beatbox Leisure Operations Ltd | Arts & recreation | 2023 |
| Beau Beau Ayrshire Limited | Wholesale & retail | 2025 |
| Beaufort Bardot Limited | Financial services | 2021 |
| Beauty Spot (Ayrshire) Ltd | Other services | 2026 |
| Beauty Spot Spa Limited | Other services | 2023 |
| BEC Devine Limited | Information & communication | 2025 |
| BED Bugs Experts Limited | Administrative & support | 2016 |
| Beech Tree International Ltd | Financial services | 2025 |
| Beechknowe Farm Ltd | Agriculture & fishing | 2026 |
| Beeswax Consultancy (Scotland) Limited | Professional & scientific | 2011 |
| Beezer Limited | Information & communication | 2014 |
| Believe Ayrshire C.I.C. | Health & social care | 2023 |
| Belkenross Limited | Professional & scientific | 2009 |
| Bella & Duck Ltd | Professional & scientific | 2026 |
| Belle View Property Development Ltd | Real estate | 2013 |
| Belleham Limited | Wholesale & retail | 2018 |
| Belleisle Conservatory Limited | Administrative & support | 2010 |
| Belleisle Property Investments Ltd | Real estate | 2018 |
| Bellfield Capital Ltd | Professional & scientific | 2022 |
| Bellingo Company LP | | 2014 |
| Bellmont Stores Ltd | Wholesale & retail | 2021 |
| Bellslea Farm Eggs Ltd | Agriculture & fishing | 2024 |
| Bellslea Hills Limited | Other services | 2022 |
| Bellslea Ltd | Agriculture & fishing | 2018 |
| Belmont AYR Limited | Real estate | 2026 |
| Belmont Builders Ltd | Construction | 2012 |
| Belmont Property Estate Agents Ltd | Real estate | 2025 |
| Benblair Consulting Ltd | Professional & scientific | 2023 |
| Bene-Fit (Auchincruive) Ltd | Arts & recreation | 2022 |
| Bene-Fit Health & Fitness AYR Ltd | Arts & recreation | 2017 |
| Benefi Ltd | Financial services | 2025 |
| Bennett's Holdco Limited | Financial services | 2021 |
| Bens and Glens Ltd | Manufacturing | 2021 |
| BER Consulting Limited | Information & communication | 2025 |
| Berkley Homes Limited | Construction | 1987 |
| Beross LP | | 2014 |
| Bespecific Limited | Information & communication | 2025 |
| Bespoke Partnerships (UK) Ltd | Professional & scientific | 2020 |
| Bespoke Wigs by Kelly Ltd | Other services | 2022 |
| Best Foot Forward (AYR) Limited | Health & social care | 2010 |
| Best Scottish Cottages X Ltd | Professional & scientific | 2022 |
| Best Tech Brands LP | | 2016 |
| Beti Reilly (Hairstylists) Limited | Other services | 1990 |
| Betty Martin Productions Ltd | Arts & recreation | 2018 |
| Beyond QSR Ltd | Hospitality | 2025 |
| Beyondclean Ltd | Administrative & support | 2024 |
| Bfjc Holdings Limited | Professional & scientific | 2023 |
| Bhaile Craft Bakery Ltd | Manufacturing | 2016 |
| Bhumi Energy Atelier Ltd | Wholesale & retail | 2025 |
| Biarritznovo LP | | 2014 |
| Bifold and Sliding Doors Scotland Limited | Manufacturing | 2016 |
| Big Blue Dog Design Limited | Professional & scientific | 2002 |
| Big Burd Beauty Ltd | Other services | 2023 |
| Big Mosside Limited | Financial services | 2023 |
| Big Pond Digital Ltd | Professional & scientific | 2013 |
| Bigbitesayr Limited | Hospitality | 2025 |
| Bigtincan UK Limited | Information & communication | 2014 |
| Bike AYR Ltd. | Wholesale & retail | 2008 |
| Billy Mcguire Joinery & Building Ltd | Construction | 2022 |
| Biofuels Group Limited | Energy | 2021 |
| Biohazard Airsoft Ltd | Arts & recreation | 2019 |
| Biostrive Ltd | Manufacturing | 2025 |
| Birniehill Grazings & Company | | 1990 |
| Birthsparks Ltd | Health & social care | 2012 |
| Bitcoin Scotland Ltd | Extraterritorial | 2022 |
| BK Heating Solutions Limited | Construction | 2024 |
| Black FOX Digital (Scotland) Ltd | Professional & scientific | 2025 |
| Black Wave Media Ltd | Information & communication | 2025 |
| Blacks Bar 16 Ltd | Hospitality | 2024 |
| Blackstone IT Limited | Information & communication | 2009 |
| Blain Agri Ltd. | Agriculture & fishing | 2017 |
| Blastfitness Gym Limited | Arts & recreation | 2015 |
| Bleescorp LP | | 2015 |
| Blink Imaging Ltd | Professional & scientific | 2005 |
| Block 321 Limited | Wholesale & retail | 2025 |
| Blossom Apartments Ltd | Households | 2023 |
| Blue Rock Brokers (Holdings) Ltd | Financial services | 2014 |
| Blue Rock Insurance Brokers Ltd | Financial services | 2014 |
| Blue Sky Engines Limited | Manufacturing | 2012 |
| Blue Square (Scotland) Ltd | Financial services | 2021 |
| BM Developments Scotland Ltd | Construction | 2024 |
| BNC Gibbons Limited | Wholesale & retail | 2011 |
| Bobin Ltd | Wholesale & retail | 2020 |
| Body Art (AYR) Limited | Other services | 2000 |
| Bodycore Ltd | Real estate | 2025 |
| Boka Group LP | | 2016 |
| Bold Mango Media Ltd | Professional & scientific | 2021 |
| Bolton Installations Ltd | Construction | 2022 |
| Bookworm Publishing Ltd | Information & communication | 2014 |
| Boom & Mini Boom Ltd | Wholesale & retail | 2016 |
| Bootneck Ltd | Wholesale & retail | 2022 |
| Boswell Properties Limited | Real estate | 2015 |
| Bothy Property Limited | Real estate | 2018 |