| Ross Advisory Services Limited | Real estate | 1976 |
| Roundchase Limited | Construction | 1988 |
| Rundle and Co Agri Ltd | Agriculture & fishing | 2006 |
| Ryan and Daniel Building Contractors Limited | Wholesale & retail | 1983 |
| Ryan Media and Research Limited | Professional & scientific | 2003 |
| S a C Developments Ltd. | Hospitality | 1989 |
| S Rendle Limited | Construction | 2006 |
| S.M.T. Associates (South West) Ltd | Professional & scientific | 2002 |
| SAM Edwards & Company Limited | Wholesale & retail | 1948 |
| Sam's (Fowey) Limited | Hospitality | 2003 |
| Sandows Garage Limited | Wholesale & retail | 2003 |
| Sandy Acres Coastal Estate Limited | Hospitality | 2017 |
| Saprs Limited | Real estate | 2008 |
| Schemebase Residents Management Limited | Households | 1986 |
| Seaquest Freehold Ltd | Financial services | 2024 |
| Seasons Estate Agents Ltd | Real estate | 2006 |
| Seaworx Limited | Professional & scientific | 2017 |
| Selleck Nicholls Holdings Limited | Professional & scientific | 2004 |
| Seven Tenths Ltd | Wholesale & retail | 1994 |
| Shanaz Indian Restaurant Ltd | Hospitality | 2003 |
| Sharps of Truro Limited | | 1987 |
| Shellware Engineering Limited | Information & communication | 1992 |
| Silauk Ltd | Health & social care | 2026 |
| Silverlake Design Limited | Professional & scientific | 2007 |
| SIM General Repairs Ltd | Manufacturing | 2017 |
| Simply Blue Management Top Co UK Ltd | Energy | 2023 |
| Skincare Cornwall Ltd | Wholesale & retail | 2008 |
| Slightly Choppy Ltd | Wholesale & retail | 2024 |
| Slipway & Anchorage Limited | Professional & scientific | 1996 |
| Smart Bluefrog Limited | Agriculture & fishing | 2011 |
| Smugglers Ride Management Company (1996) Limited | Real estate | 1996 |
| Smythe Construction Limited | Construction | 2014 |
| Socks Medical Limited | Real estate | 2022 |
| South West Solar Ltd | Construction | 2006 |
| South West Yacht Brokers Limited | Wholesale & retail | 1998 |
| Sparkstone Limited | Hospitality | 1993 |
| Speartech Engineering Solutions Limited | Wholesale & retail | 2005 |
| Specialised Industrial Chemicals Limited | Manufacturing | 1995 |
| Spencer-Carter Limited | Agriculture & fishing | 1997 |
| Spinnaker International Limited | Administrative & support | 2017 |
| Springboard Leaders Ltd | Information & communication | 2025 |
| ST Austell Building Services LLP | | 2003 |
| ST Moritz Hotel & Garden Villas Limited | Hospitality | 2005 |
| ST. Anthony Holiday Cottages Limited | Hospitality | 2003 |
| ST. Columb Financial Services Ltd | Financial services | 2004 |
| ST. Ives Food Company Limited | Wholesale & retail | 2002 |
| ST. Joseph's School Launceston | Education | 1983 |
| ST. Mary's Management Company (Falmouth) Limited | Households | 1979 |
| ST. Merryn Garage Workshop Limited | Wholesale & retail | 1977 |
| ST. Moritz Developments Limited | Construction | 2001 |
| St.Austell Brewery Company Limited | Manufacturing | 1910 |
| St.Austell Golf Estates Limited | Arts & recreation | 1926 |
| Stanmore Flats Management Company (Falmouth) Limited | Households | 1983 |
| Stein's Trading Limited | Hospitality | 2014 |
| Stenlakes Limited | Water & waste | 2003 |
| Stephen Blundell Ltd | Construction | 2021 |
| Steppa Engineering Limited | Professional & scientific | 2024 |
| Steve Andrews (Tyres) Limited | Wholesale & retail | 1995 |
| Stockchance Limited | Wholesale & retail | 1990 |
| Stocks & Sons (Haulage Contractors) Limited | | 1975 |
| Stonewood Court Limited | Real estate | 2004 |
| Stratton Place Flats Limited | Households | 1989 |
| Subaqua Pro Limited | Wholesale & retail | 1978 |
| Sun Meadow CD Ltd | Agriculture & fishing | 2025 |
| Sweetlime Studio Limited | Wholesale & retail | 2014 |
| Sweetreat Ltd | Hospitality | 2000 |
| T & P Developments Kilkhampton Limited | Construction | 2005 |
| T&G Clothing (UK) Limited | Transport & logistics | 2007 |
| Tamar Valley Homes Ltd | Construction | 2015 |
| Tamar Valley Transport Company Limited | Transport & logistics | 1974 |
| Tamar View Nurseries Ltd | Wholesale & retail | 2006 |
| Tamara Fishing Limited | Agriculture & fishing | 2005 |
| Tandoe Ltd | Wholesale & retail | 2025 |
| Tasnim Catering Ltd | Hospitality | 2018 |
| Taspro Limited | Professional & scientific | 1977 |
| Teagle Brothers Limited | Real estate | 2007 |
| Terry Morris Agriculture Limited | Construction | 2002 |
| THE Bathroom Studio Limited | Wholesale & retail | 2001 |
| THE Brendon Arms Limited | Hospitality | 2002 |
| THE Celtic Lands Design Company Limited | Extraterritorial | 2023 |
| THE Cornish Oggie Oggie Pasty Company (Devon) Limited | Wholesale & retail | 1993 |
| THE Cornish Oggie Oggie Pasty Company Limited | Professional & scientific | 1993 |
| THE Delabole Slate Company Limited | Mining & quarrying | 1999 |
| THE Eden Trust | Education | 2002 |
| THE Edge Surf Company Limited | Wholesale & retail | 2002 |
| THE Magellan Cruise Line (U.K.) Limited | | 1990 |
| THE Nare Hotel Company Limited | Hospitality | 1988 |
| THE Old Jeans Store Limited | Wholesale & retail | 1995 |
| THE Old School Court (Wadebridge) Limited | Real estate | 1996 |
| THE Orchard Management Company (Newquay) Limited | Households | 1999 |
| THE Perception Company Limited | Construction | 1996 |
| THE Performance Factor Limited | Professional & scientific | 1997 |
| THE Pioneer Environmental Building Company Limited | Construction | 2002 |
| THE Property Shop (Cornwall) Limited | Real estate | 2004 |
| THE Real Boat Company Limited | Arts & recreation | 2005 |
| THE Riverside at Helford Limited | Hospitality | 1996 |
| THE Strand Shopping Centre Barber Ltd | Other services | 2023 |
| THE Studio Addlestone Limited | Other services | 2004 |
| Theredhot Co Limited | Construction | 2004 |
| Thomas Homes ( Cornwall ) Limited | Construction | 2007 |