| R. Love & Co. | | 1997 |
| R.S. Duncan (Plant Hire) Limited | Construction | 2004 |
| RAD Limited | Hospitality | 1995 |
| Rainbow Cottage Nursery Limited | Education | 2005 |
| Raith Farms | | 1999 |
| RD Removal Ltd | Administrative & support | 2017 |
| Reid & Reid | | 1990 |
| Repairport Limited | Real estate | 2001 |
| Rightcars Limited | Wholesale & retail | 2003 |
| Rltd Ltd | Administrative & support | 2017 |
| Robert Howie & Sons | Manufacturing | 1947 |
| Rodolfo Pediani (Hair Stylist) Limited | Real estate | 1940 |
| Rowallan Limited | Hospitality | 1991 |
| Rowanbrae Limited | Hospitality | 1992 |
| Royal Hotel (Girvan) Limited | Hospitality | 2002 |
| Rugbyplus Limited | Wholesale & retail | 2018 |
| S K F Limited | Construction | 2004 |
| S R Mccolm Limited | Real estate | 2003 |
| S. & J. Mccarroll & Company Limited | | 1964 |
| Saac 2 Limited | Financial services | 2024 |
| Sandfirs Investments Limited | Real estate | 1998 |
| Sandy Anderson Transport Ltd | Transport & logistics | 1997 |
| Sanghera & Sons Ltd | Wholesale & retail | 2026 |
| Scotch Thistle Limited | Real estate | 2021 |
| Scotplants Limited | Agriculture & fishing | 1990 |
| Scottish Aviation Limited | Extraterritorial | 1935 |
| Seaford Developments Limited | Real estate | 1978 |
| Siena Developments Limited | Hospitality | 2005 |
| Simply Hair & Beauty Ltd. | Other services | 2005 |
| Skene Group Construction Services Limited | Mining & quarrying | 2000 |
| Skene Group Quarries Limited | Professional & scientific | 2000 |
| Smith's Coaches (Patna) Ltd | Transport & logistics | 2017 |
| Sorn Mains Farming Company | | 1991 |
| South Shaw Farming Company | | 1990 |
| Southbar Transport Limited | Transport & logistics | 2006 |
| Spectacular Growth Limited | Extraterritorial | 2004 |
| Springbank Farm | | 1991 |
| SRK (Scotland) Ltd. | Professional & scientific | 2007 |
| Stanecastle Consulting Limited | Professional & scientific | 2003 |
| Stenlake Publishing Limited | Information & communication | 2003 |
| Stowbrook Limited | Hospitality | 1991 |
| Strathclyde Hydraulics Limited | Manufacturing | 1980 |
| Strathrise Limited | Hospitality | 2011 |
| Sunnyside Nursery (Kilwinning) Limited | Wholesale & retail | 2003 |
| Swift 2 Limited | Energy | 2025 |
| Swift 3 Limited | Energy | 2025 |
| Swift 4 Limited | Energy | 2025 |
| T. & T. Anderson | | 2000 |
| Tardoes Farming Company | | 1998 |
| Thaw & Campbell (Contracts) Limited | Professional & scientific | 1986 |
| THE Aquatic Coleoptera Conservation Trust | Professional & scientific | 2006 |
| THE Bald Eagle Golf Company Limited | Hospitality | 1998 |
| THE Craig Farm Partnership | | 1996 |
| THE Cutting Corner (Ayrshire) Limited | Real estate | 2004 |
| THE Emmanuel Christian Centre | Other services | 2006 |
| THE Findlay-Cuthbertson Partnership | | 1994 |
| THE Findlay-Leitch Partnership | | 1994 |
| THE Firm of Townhead of Greenock Farm | | 2001 |
| THE James Boswell Foundation | Extraterritorial | 2001 |
| THE Kilmarnock Football Club Limited | Arts & recreation | 1906 |
| THE Mane MAN Limited | Other services | 2003 |
| THE Midland Farm Partnership | | 1995 |
| THE Orchardton Farming Company | | 2002 |
| THE Styles Bank Limited | Information & communication | 2006 |
| THE Western Meeting Club 2003 Limited | Real estate | 2003 |
| Thirdpart Properties Limited | Real estate | 2004 |
| Thomas a Barr | | 2003 |
| Thomas Blair Engineering Limited | Professional & scientific | 2007 |
| Thomas Grant (Brocklees) Limited | Construction | 2003 |
| Tillydesk Farms | | 1991 |
| Titwood Farms | | 1989 |
| TLP Systems Limited | Hospitality | 2000 |
| TO Properties Saltcoats Limited | Administrative & support | 2001 |
| Transition Interiors Limited | Construction | 1978 |
| Troon Textiles LLP | | 2005 |
| Turnberry Holiday Park (Scotland) Ltd | Hospitality | 2023 |
| Turnbull Tyres Limited | Wholesale & retail | 2006 |
| Tynetside Limited | Energy | 2021 |
| Universal Education & Training Limited | Education | 2004 |
| Utopia Computers Limited | Manufacturing | 2000 |
| Vallson Engineering Limited | | 2004 |
| Victors | | 1986 |
| Volifinn Limited | Other services | 2022 |
| W I & a Gilbert Limited | Construction | 2003 |
| W.J. Milne Limited | Administrative & support | 1917 |
| Walker Street Garage | | 1987 |
| Wallace Consultancy Group Ltd | Administrative & support | 2016 |
| Walter Brown (Building Contractors) Limited | Construction | 1964 |
| Warden Motors Limited | Wholesale & retail | 2007 |
| Water Distribution and Energy Services Limited | Water & waste | 2006 |
| WE ARE Sure Limited | Information & communication | 2012 |
| Wecc Services Limited | Professional & scientific | 2006 |
| Wellshore Limited | Real estate | 2006 |
| West Coast Contractors Limited | Construction | 1964 |
| Western House Catering Limited | Hospitality | 2004 |
| Western Market Ltd | Professional & scientific | 2004 |
| Wheatrig Farming Company | | 1989 |
| Whinfield Solutions Limited | Information & communication | 2003 |
| Whiteford Smith Associates Limited | Professional & scientific | 2004 |
| Wildcat Road Limited | Wholesale & retail | 2005 |