| Romaplan Property Management Limited | Households | 1998 |
| Rose-Wragg Creative Ltd | Arts & recreation | 2026 |
| Round Hill Farm Limited | Agriculture & fishing | 2005 |
| Route A66 Classic Car Hire Limited | Administrative & support | 2024 |
| Rowley Jayne Limited | Professional & scientific | 2015 |
| ROY Young Limited | Wholesale & retail | 2008 |
| Rumney Ltd | Professional & scientific | 2026 |
| Rural Communication Solutions Limited | Administrative & support | 2003 |
| S & a Williamson Limited | Wholesale & retail | 2002 |
| S & L Cottam Limited | Hospitality | 2019 |
| S & M Carr Ltd | Professional & scientific | 2015 |
| S B Welding and Fitting Ltd | Manufacturing | 2026 |
| S J Todhunter Limited | Real estate | 2012 |
| S Knowles UXO Consultancy Ltd | Other services | 2022 |
| S Lightfoot Limited | Agriculture & fishing | 2003 |
| S&K Barton Lettings Ltd | Real estate | 2026 |
| S&M Pizzeria Limited | Hospitality | 2025 |
| Sadson Properties Ltd | Real estate | 2026 |
| SAM Hagan Leisure (UK) Limited | Hospitality | 1992 |
| Sandy Lodge Investments Limited | Financial services | 2026 |
| Sassy Property Styling Ltd | Professional & scientific | 2021 |
| Scholars Green (Wigton) Management Company Limited | Households | 2012 |
| Scott Nuclear Limited | Professional & scientific | 2026 |
| SD Engineering Design Limited | Professional & scientific | 2003 |
| Sealy United Kingdom Limited | Manufacturing | 2020 |
| SEC a Grand Fella Limited | Wholesale & retail | 2022 |
| Seventyone Bikes Ltd | Wholesale & retail | 2023 |
| SG Mechanical Services Ltd | Wholesale & retail | 2020 |
| Shakti Pumps UK Ltd | Manufacturing | 2018 |
| Sharp Pumps UK Ltd | Manufacturing | 2022 |
| Shaun Bell Electrical Limited | Construction | 2007 |
| Shellian Logistics Ltd | Transport & logistics | 2025 |
| Shirley Muir Associates Ltd | Professional & scientific | 2010 |
| Shone Geotechnical Ltd | Construction | 2022 |
| Shoppinglane Ltd | Wholesale & retail | 2018 |
| Silloth Motorcycle Museum Ltd | Arts & recreation | 2025 |
| Silloth Scrap Metals Limited | Wholesale & retail | 2023 |
| Silver Lady Holdings Limited | Transport & logistics | 2025 |
| Silverback Tree Services Ltd | Agriculture & fishing | 2023 |
| Simon Huntington Limited | Wholesale & retail | 2007 |
| Skiddaw View Holiday Park Limited | Hospitality | 2003 |
| Skyward Scaffolding Limited | Administrative & support | 2025 |
| SLD Logistics Limited | Transport & logistics | 2020 |
| Slmh Ltd | Information & communication | 2024 |
| Slytech Ltd | Information & communication | 2025 |
| Smcph Ltd | Hospitality | 2019 |
| Snowhill Stone Ltd | Mining & quarrying | 2014 |
| Softsouhail Ltd | Information & communication | 2025 |
| Soil Stabilisation (U.K.) Ltd | Construction | 1973 |
| SOLO82 Limited | Wholesale & retail | 2019 |
| Solway Coast Glamping Ltd | Hospitality | 2020 |
| Solway Estates Limited | Construction | 2020 |
| Solway Geoscience Ltd | Construction | 2017 |
| Solway Health and Safety Training Ltd | Professional & scientific | 2019 |
| Solway Heat & Power Limited | Energy | 2010 |
| Solway Logistics Ltd | Transport & logistics | 2025 |
| Solway Pharm Health Limited | Extraterritorial | 1987 |
| Solway Plain Futures Limited | Hospitality | 2009 |
| Solway Private Hire Ltd | Transport & logistics | 2025 |
| Solway Renovations Limited | Construction | 2019 |
| Sophia Yvonne Ltd | Wholesale & retail | 2025 |
| Spacebook Ltd | Information & communication | 2013 |
| Spacewright Ltd | Real estate | 2024 |
| Sparrow Digital Ltd | Information & communication | 2017 |
| Spencer Graham Coaches Limited | Transport & logistics | 2016 |
| Spittal Farm Management Limited | Real estate | 2011 |
| SRB Logical Solutions Ltd | Information & communication | 2026 |
| Srfx Capital Ltd | Financial services | 2020 |
| ST & RT LEE Ltd | Agriculture & fishing | 2024 |
| Stamper & Co Accountants Ltd | Professional & scientific | 2012 |
| Stamper Motorsport Limited | Wholesale & retail | 2002 |
| Stamper Properties Limited | Real estate | 2008 |
| Stanford Knights Letting Limited | Real estate | 2012 |
| Stanley James Press Limited | Manufacturing | 2012 |
| Stanyer Rooms Limited | Real estate | 2018 |
| Station Road Garage Bodyworks Ltd | Wholesale & retail | 2024 |
| Station Road Garage Car Sales Ltd | Wholesale & retail | 2024 |
| Steadman Development Limited | Real estate | 2008 |
| Steve Hardaker (Holdings) Limited | Financial services | 2023 |
| Steve Hardaker Limited | Financial services | 2007 |
| Stevens Equipment Rental Limited | Construction | 2005 |
| Stewart Allan Limited | Wholesale & retail | 2001 |
| Striving for Summits Ltd | Administrative & support | 2026 |
| Studio P T Limited | Arts & recreation | 2023 |
| SUCCESS4PROJECTS Ltd | Administrative & support | 2008 |
| Sugar on Solway Limited | Wholesale & retail | 2016 |
| Sustainable Engineering Solutions Ltd | Professional & scientific | 2023 |
| T J Wassell Engineering Limited | Manufacturing | 2014 |
| T. & D. Steele Limited | Wholesale & retail | 1987 |
| TA Byers Properties | Real estate | 2014 |
| TAJ Food Wigton Limited | Hospitality | 2023 |
| Tanglewood Caravan Park | Hospitality | 2009 |
| Targate (UK) Limited | Information & communication | 2003 |
| Tarnrigg Limited | Agriculture & fishing | 2021 |
| Tattieman Ltd | Hospitality | 2026 |
| Taylor Farming Limited | Agriculture & fishing | 2025 |
| Taylormade Engineering Limited | Manufacturing | 2014 |
| TD Agriworks Ltd | Professional & scientific | 2020 |
| Technique Hair Studio Ltd. | Other services | 2002 |
| Teepee Parties Ltd | Arts & recreation | 2024 |