| Rennie Welch Audit Limited | Professional & scientific | 2002 |
| Rennie Welch LLP | | 2006 |
| Renwick Country Properties Limited | Real estate | 2003 |
| Restructuring Advisory Scotland Ltd | Professional & scientific | 2024 |
| Ricx Ltd | Wholesale & retail | 2025 |
| Rocklug Tyres Limited | Extraterritorial | 1995 |
| Roromore Hydro Ltd | Energy | 2009 |
| Rosie Hobbs Consultancy Ltd | Professional & scientific | 2011 |
| Rossmuir Limited | Hospitality | 2015 |
| Rough Castle Experiences Limited | Professional & scientific | 2016 |
| Route 68 Garage Limited | Wholesale & retail | 2024 |
| RRS Farming Limited | Agriculture & fishing | 2010 |
| S Grant Cleaning Ltd | Administrative & support | 2019 |
| SAB Services Kelso Limited | Wholesale & retail | 2023 |
| Saltire Energy Consultants Ltd | Construction | 2021 |
| Salus PAM Ltd | Professional & scientific | 2022 |
| Sanday Bioscience Limited | Information & communication | 2021 |
| SBO Properties (Scotland) Ltd | Real estate | 2023 |
| Schofield Dyers Holdings Ltd | Financial services | 2020 |
| Scot Borders Enduro Club Ltd | Arts & recreation | 2022 |
| Scotch Communications Limited | Professional & scientific | 2012 |
| Scotia Works Limited | Manufacturing | 2023 |
| Scotmas Biosecurity Limited | Water & waste | 2020 |
| Scotmas Consumer Solutions Ltd | Manufacturing | 2019 |
| Scotmas Group Limited | Financial services | 2020 |
| Scotmas Limited | Manufacturing | 1998 |
| Scott & Foggon Ltd. | Construction | 2002 |
| Scott Douglas Plumbing & Heating Limited | Construction | 2012 |
| SDF Vimbo Ltd | Financial services | 2021 |
| SDH Limited | Professional & scientific | 1986 |
| Select Apartments Limited | Real estate | 2025 |
| SG Window Cleaning Services Ltd | Administrative & support | 2019 |
| Sgwcs Ltd | Administrative & support | 2024 |
| SH Deli Limited | Wholesale & retail | 2022 |
| Shaven Gooseberry Ltd | Wholesale & retail | 2020 |
| Shields Construction Management Ltd | Professional & scientific | 2020 |
| Shortwood Harvesting Ltd | Agriculture & fishing | 2012 |
| SJE Joinery Limited | Construction | 2021 |
| Skinscape Academy Ltd | Other services | 2026 |
| SKS Joinery Limited | Construction | 2002 |
| Smamos Ltd | Professional & scientific | 2022 |
| Solais Counselling Ltd | Real estate | 2020 |
| Soma Osteopathy Ltd | Health & social care | 2015 |
| Sonic Fresh Ltd | Hospitality | 2026 |
| Sparkle Hardware Ltd | Wholesale & retail | 2018 |
| Sportsmed Solutions Limited | Arts & recreation | 2004 |
| Sprouston Community Trust | Households | 2005 |
| Sspp Limited | Real estate | 2023 |
| Steven Mcdonald Granite Ltd | Manufacturing | 2022 |
| Stewart Park Limited | Transport & logistics | 2002 |
| Stewart Pearson Services Ltd | Agriculture & fishing | 2017 |
| Stratford T&P Ltd | Professional & scientific | 2021 |
| Streets Ahead (Borders) | Health & social care | 1987 |
| Susan Hewit Limited | Financial services | 2014 |
| SV Medical Ltd | Education | 2025 |
| SXP Limited | Professional & scientific | 2018 |
| Symonds Taylor NE LLP | | 2015 |
| T W & T B Edgar (Holdings) Limited | Financial services | 2023 |
| T W & T B Edgar Limited | Agriculture & fishing | 2008 |
| Taijo Limited | Financial services | 2019 |
| Tailored Training Limited | Health & social care | 2021 |
| Tan-Hunter Specialist Imaging Ltd | Professional & scientific | 2023 |
| Tarry’S Agricultural Vermin Control Ltd | Administrative & support | 2025 |
| Task Priority Coffee Co. Limited | Manufacturing | 2021 |
| TAY Salmon FLY Limited | Agriculture & fishing | 2013 |
| TD Building & Maintenance (Borders) Ltd | Construction | 2025 |
| TD5 Training Solutions Limited | Education | 2023 |
| Tdct Limited | Agriculture & fishing | 2011 |
| Teostar Services Ltd | Wholesale & retail | 2019 |
| Teviot Escapes Ltd | Hospitality | 2026 |
| Teviot Homes Limited | Construction | 2025 |
| TFJ Property Limited | Real estate | 2024 |
| THE Attonburn Farm Partnership LP | | 1989 |
| THE Bar (Scotland) Limited | Hospitality | 2008 |
| THE Barkley Fitness Ltd | Arts & recreation | 2022 |
| THE Carpet Shop (Kelso) Ltd | Construction | 2025 |
| THE Cross Keys Hotel | | 2002 |
| THE Good Gift Co. Limited | Wholesale & retail | 2004 |
| THE Helpdesk Scotland Limited | Extraterritorial | 1999 |
| THE Houndridge Partnership | | 2002 |
| THE Hume Castle Preservation Trust | Administrative & support | 2005 |
| THE Knowes Eatery and Coffee House Ltd | Hospitality | 2022 |
| THE Muscle Factory (Borders) Ltd | Arts & recreation | 2025 |
| THE Oracle Cashmere Limited | Manufacturing | 2018 |
| THE Scottish Racing Academy | Education | 2019 |
| THE Smart Heat & Light Company Limited | Construction | 2005 |
| THE Tweed Property Hub Ltd | Real estate | 2025 |
| THE Wagyu PIE Company Ltd | Extraterritorial | 2023 |
| THE Water Dog Ltd | Hospitality | 2025 |
| Thermafy Eco Solutions Limited | Information & communication | 2021 |
| Thermafy Group Ltd | Wholesale & retail | 2015 |
| Thermafy Protect Ltd | Wholesale & retail | 2020 |
| Thermaheat Limited | Construction | 1994 |
| Thirlestane Castle Events Ltd | Hospitality | 2021 |
| Thirlestane Castle Ltd | Hospitality | 2022 |
| Thirlestane Park Ltd | Hospitality | 2018 |
| Tireil Limited | Professional & scientific | 2012 |
| Titan 365 Ltd | Arts & recreation | 2018 |
| TOM Forsyth Consulting Ltd | Professional & scientific | 2014 |
| Total Construction Scotland Ltd | Construction | 2023 |