| Poole Joiners Ltd | Construction | 2024 |
| Port Bannatyne Marina Limited | Transport & logistics | 2003 |
| Positive Pedals CIC | Manufacturing | 2025 |
| Prodive Consultancy Ltd | Professional & scientific | 2012 |
| R H Management Services Limited | Professional & scientific | 2024 |
| R. & P. Mcalister Langalbuinoch Farm | | 1998 |
| RCS Scot Ltd | Wholesale & retail | 2023 |
| Regal Enterprise Bute Ltd | Real estate | 2024 |
| Reggie's Rental's Ltd | Real estate | 2024 |
| Ronnie Hair Limited | Professional & scientific | 2018 |
| Rose Dovey Consulting Ltd | Professional & scientific | 2022 |
| Rothesay Fast Foods Limited | Hospitality | 2024 |
| Rothesay Food Ltd | Hospitality | 2026 |
| Safe Hook Lifting Services Ltd | Construction | 2019 |
| Scalpsie Ltd | Agriculture & fishing | 2023 |
| Scoulag Butts Farm Free Range Hens | | 1995 |
| Scoulag Farmers | | 1995 |
| Sd&Gm Ltd | Professional & scientific | 2017 |
| Shawfield Building Contractors Ltd | Construction | 2024 |
| Sizzler Cater Limited | Hospitality | 2024 |
| Soltire Stays Ltd | Real estate | 2025 |
| Solution Support Services Scotland Ltd | Professional & scientific | 2013 |
| Sterling Yacht Services Limited | Manufacturing | 2008 |
| Story Wagon Community Interest Company | Arts & recreation | 2022 |
| Superior Solutions Bute Ltd | Construction | 2019 |
| TCD Environmental Services Ltd | Professional & scientific | 2025 |
| THE Bute VET Ltd | Professional & scientific | 2024 |
| THE Carpet Warehouse (Bute) Ltd. | Wholesale & retail | 2007 |
| THE Galatea Bar (Rothesay) Ltd | Hospitality | 2018 |
| THE Port Inn Limited | Hospitality | 2014 |
| THE Rabbie Burns Ltd | Hospitality | 2021 |
| THE Rabbies Ltd | Hospitality | 2023 |
| THE Sulking Room Ltd | Hospitality | 2022 |
| THE Travel Parrot Limited | Administrative & support | 2021 |
| THE Wallace Corporation Ltd. | Extraterritorial | 1996 |
| THE WEE Scottish Shop Ltd | Wholesale & retail | 2018 |
| THE World Changed Ltd | Professional & scientific | 2017 |
| Tinytigerbute Ltd | Information & communication | 2023 |
| Toba Tabo Limited | Wholesale & retail | 2025 |
| Toffos Ltd. | Wholesale & retail | 2011 |
| Tripswitch Productions Ltd | Information & communication | 2014 |
| Turkish Grill Bute Limited | Hospitality | 2018 |
| Turkish Grill Rothesay Ltd | Hospitality | 2026 |
| WM Skelton & Co Limited | Professional & scientific | 2015 |
| Wright Pryce Roofing Contractors Ltd | Construction | 2022 |
| ZAP and Scrub Ltd | Other services | 2025 |