| SJ Retail Stores Limited | Wholesale & retail | 2025 |
| SJR Hobbies Ltd | Wholesale & retail | 2025 |
| SK Brokers Ltd | Wholesale & retail | 2008 |
| Skyline Tree Surgery Limited | Administrative & support | 2023 |
| Slab Tiles Limited | Wholesale & retail | 2021 |
| Slariens Ltd | Financial services | 2018 |
| Slee Blackwell Solicitors LLP | | 2016 |
| Sleepy OWL Limited | Hospitality | 2018 |
| SLM Scientific Studio Ltd | Information & communication | 2026 |
| Smallridge Bros Limited | Wholesale & retail | 2008 |
| Smart Fone Case Limited | Administrative & support | 2019 |
| Smartfone World Ltd | Wholesale & retail | 2025 |
| Smartline Investments Ltd | Construction | 2021 |
| Smco MED Ltd | Wholesale & retail | 2020 |
| Smiles Cosmetic Dentures Limited | Health & social care | 2012 |
| Smith Automotive Services Limited | Wholesale & retail | 2026 |
| Smsh Ltd | Financial services | 2025 |
| Sneak-A-Peek Ultrasound LLP | | 2020 |
| Snow Limits Consulting Ltd | Professional & scientific | 2020 |
| SNR Roofing Ltd | Construction | 2021 |
| Sohal A2Z Properties Ltd | Real estate | 2025 |
| Solar PV Technology Limited | Construction | 2010 |
| Solaris Healthcare Network Limited | Professional & scientific | 1999 |
| Solman Davis Limited | Construction | 2007 |
| Somewhere Elsewhere Ltd | Hospitality | 2026 |
| Soul (London) Limited | Professional & scientific | 2013 |
| Soulfull Journeys Ltd | Administrative & support | 2024 |
| Soundbite Culture Ltd | Administrative & support | 2014 |
| South Catering Limited | Wholesale & retail | 2025 |
| South Molton Scaffolding Limited | Administrative & support | 2004 |
| South Molton Taxi Service Ltd | Transport & logistics | 2003 |
| South West Allegiance Ltd | Arts & recreation | 2020 |
| South West Care Supplies Limited | Wholesale & retail | 2008 |
| South West Catering N Beverages Limited | Hospitality | 2025 |
| South West Counties Allotment Association Community Interest Company | Agriculture & fishing | 2008 |
| South West Developments Ltd | Construction | 2025 |
| South West Heat Pumps Ltd | Construction | 2009 |
| South West Palliative Care Ltd. | Health & social care | 2011 |
| South West Peninsula Care Ltd. | Health & social care | 2011 |
| South West Precise Properties Ltd | Real estate | 2015 |
| South West Sterilizer Services Ltd | Health & social care | 2023 |
| South West Timber Frame Ltd | Construction | 2013 |
| South West Vw's Ltd | Wholesale & retail | 2014 |
| South West Windows Limited | Construction | 2010 |
| Southern Partridges Limited | Agriculture & fishing | 1979 |
| Southfork Cycles Ltd | Wholesale & retail | 2026 |
| Southside Vehicle Parts and Repairs Ltd | Wholesale & retail | 2025 |
| Southwest Storage Solutions Ltd | Transport & logistics | 2025 |
| Southwest Storage Solutions Van Hire Ltd | Administrative & support | 2025 |
| Space to BE Wellbeing CIC | Other services | 2024 |
| Spark Marketing Services Limited | Professional & scientific | 2016 |
| Sparkly Jewels Limited | Wholesale & retail | 2016 |
| Spear Building Contractors Limited | Construction | 2025 |
| Speed Communications Agency Limited | Professional & scientific | 1991 |
| Speed JB Ltd | Information & communication | 2024 |
| Spill the Beans (Barnstaple) Ltd | Hospitality | 2025 |
| Spirebourne Limited | Water & waste | 1980 |
| Springfield (UK) Ltd | Information & communication | 1994 |
| Springfield Nursery Limited | Health & social care | 2012 |
| Spurway Gardens Management Ltd | Households | 2021 |
| SQ Catering Limited | Hospitality | 2025 |
| Sqlworks Software Limited | Information & communication | 2013 |
| Square One Commercials Limited | Manufacturing | 2004 |
| Squarefoot Building Contractors Limited | Construction | 2016 |
| Squarefoot Plant and Tool Hire Limited | Administrative & support | 2022 |
| Squarefoot Plumbing and Heating Limited | Construction | 2022 |
| SRH 7 Commercial Ltd | Real estate | 2024 |
| SRH 7 Ltd | Real estate | 2015 |
| ST Johns Country Stores Ltd | Financial services | 2024 |
| ST Mary's (Bishops Nympton) Management Company Limited | Real estate | 2021 |
| ST. Mary's Flats (Bideford) Residents Assocaition Limited | Households | 1970 |
| St.John's Nurseries (North Devon) Limited | Wholesale & retail | 1958 |
| Stacey a Properties Ltd | Real estate | 2025 |
| Stagg Farm Services Ltd | Manufacturing | 2014 |
| Stangate 2 Limited | Real estate | 2001 |
| Stangate Properties Limited | Real estate | 2002 |
| Stanley House Accommodation Limited | Real estate | 2026 |
| Stanners Gym Ltd | Arts & recreation | 2024 |
| Stannp Ltd | Manufacturing | 2014 |
| Stanwell Drive Management Company Limited | Households | 2003 |
| Stapleton Green LLP | | 2016 |
| Star Wealth Strategic Planners Ltd | Financial services | 2023 |
| Stardent Ltd | Health & social care | 2016 |
| Start Sort Scale Ltd | Administrative & support | 2022 |
| Steadchoice (Southern) LLP | | 2021 |
| Steadchoice Limited | Real estate | 1975 |
| Steve Gibb Supply Chain Services Limited | Professional & scientific | 2020 |
| Stexsol Marine Consultancy Ltd | Professional & scientific | 2025 |
| Sticklepath Hand Car Wash Ltd | Other services | 2026 |
| Stoat Park Residents Limited | Households | 2006 |
| Stoates Mill Management Ltd | Households | 2017 |
| Stoked Vintage Retro Ltd | Wholesale & retail | 2026 |
| Stone & Creative Ltd | Other services | 2011 |
| Stone and Sons Ltd | Construction | 2023 |
| Stoppers Roller Rink Ltd | Arts & recreation | 2023 |
| Storage Space Barnstaple Ltd | Transport & logistics | 2020 |
| Storebuild Limited | Construction | 2021 |
| Storm Petrel Studios Limited | Information & communication | 2020 |
| Storm Track UK C.I.C. | Manufacturing | 2026 |
| Story Agency Limited | Professional & scientific | 2008 |