| Steve Diggers Limited | Chesterfield | 2015 |
| Steve Parker Pipeline Services Limited | Nottingham | 2009 |
| Stevemarque Limited | Aberdeen | 2020 |
| Stevenson Process Technology Ltd | Cottingham | 2016 |
| Stewart Ferris Rope Access Ltd | Glasgow | 2018 |
| Stewart Holdings Management Limited | Prescot | 2006 |
| Stiperstone Analytics Limited | Telford | 2019 |
| STL Construction Ltd | Pencaitland | 2021 |
| STL Developments Ltd | Montrose | 2014 |
| Stoke Plant Hire Limited | Earlsdon Coventry | 1988 |
| Stokey Plant Hire Limited | Telford | 1983 |
| Stone & Slate Limited | Chesterfield | 2001 |
| Stone Cliff Aggregates Ltd | Huddersfield | 2020 |
| Stone Firms Limited | Weymouth | 2004 |
| Stone International (UK) Ltd | Windsor | 2014 |
| Stone Polishing Ltd | Peterborough | 2024 |
| Stone Shippers Limited | Elland | 2000 |
| Stone Wolf Mining Limited | Chelmsford | 2024 |
| Stoneaxis Ltd | Poole | 2026 |
| Stonebuild Contracts Limited | Shepton Mallet | 2013 |
| Stoneledge Quarries Limited | Hull | 1983 |
| Stonepack Ltd | Forfar | 2006 |
| Stoneyhill Waste Management Limited | Edinburgh | 1989 |
| Stop Smoking (UK) Ltd | London | 2012 |
| Storefield Aggregates Limited | Kettering | 2009 |
| Storemco Technical Services International Limited | Aberdeen | 2006 |
| Storm Energy Ltd | Ashby-De-La-Zouch | 2013 |
| Storm Procurement Limited | Watford | 2006 |
| Storrington Sand Quarry Limited | Redhill | 2022 |
| Stowen Clean Energy Limited | Great Yarmouth | 2016 |
| Stowen Group Limited | Great Yarmouth | 2018 |
| Stowen OIL & GAS Ltd | Great Yarmouth | 2014 |
| Strachan Interventions Limited | Arbroath | 2013 |
| Stranz International Company (UK) Limited | Bedford | 2026 |
| Stratadata Limited | Woking | 1992 |
| Stratasolve Ltd | Warrington | 2006 |
| Strategic Natural Resources PLC | Warrington | 2004 |
| Strategic Reservoir Consultants Ltd | London | 2018 |
| Stratex Exploration Limited | Fareham | 2004 |
| Stratex West Africa Limited | Fareham | 2007 |
| Strathmore ROV Limited | Forfar | 2015 |
| Straththames Limited | Henley-On-Thames | 2009 |
| Stratminex Limited | London | 2026 |
| Stratonyx Energy Ltd | King'S Lynn | 2026 |
| Strauss Hecker Group Ltd | London | 2022 |
| Stravaig Subsea Ltd | Braemar | 2023 |
| Street Drilling Engineering Limited | Banchory | 2007 |
| Street Engineering (Services) Ltd | Angus | 2014 |
| Stretfordend Limited | Wilmslow | 2011 |
| Stride Networks Limited | Gravesend | 2016 |
| Striped Horse Resources Ltd. | Much Wenlock | 2018 |
| Stroma Technical Services Ltd | Wick | 2019 |
| Struan Energy Limited | Edinburgh | 1999 |
| Strudwicks Limited | Basingstoke | 2006 |
| Strumberg Ltd | Weybridge | 2018 |
| Stuart Aggregates Limited | Forsinard | 2012 |
| Stuart Mcdonald Ltd | Dundee | 2020 |
| Stuart Process Services Limited | Stockton-On-Tees | 2012 |
| Stubatron Ltd | Arbroath | 2012 |
| Studio Limited | Aberdeen | 1999 |
| Styson Construction Limited | Rotherham | 2010 |
| SUB4FIN Ltd | London | 2016 |
| Sublime Energy Ltd | London | 2022 |
| Submar Limited | Bathgate | 2006 |
| Subotics Ltd. | Pangbourne | 2016 |
| Subsea 7 I-Tech Limited | Westhill | 2013 |
| Subsea 7 Limited | Sutton | 2001 |
| Subsea 7 Offshore Resources (UK) Limited | Sutton | 2011 |
| Subsea 7 Pipeline Production Limited | Westhill | 1982 |
| Subsea 7 ROV UK Limited | Sutton | 2025 |
| Subsea Alba Limited | Inverness | 2012 |
| Subsea Commingling Ltd | Ewell Epsom | 1987 |
| Subsea Control Module Services Ltd | Fraserburgh | 2016 |
| Subsea Leasing Limited | London | 1988 |
| Subsea Minerals Ltd | Falmouth | 2000 |
| Subsea Pilot Ltd | Liverpool | 2024 |
| Subsea Pressure Controls Ltd | Aberdeen | 2019 |
| Subsea Technical & Safety Services Ltd | Ballymoney | 2017 |
| Subsea Umbilical Engineering Services Ltd | Aberdeenshire | 2007 |
| Subsoft Controls Limited | Montrose | 2008 |
| Subterra Drilling Ltd | Chatham | 2026 |
| Sukhman Haulage Ltd | Derby | 2019 |
| Sullivan Industrials Ltd | Manchester | 2025 |
| Sumatra Copper & Gold PLC | London | 2006 |
| Summit Minerals Trading Services Ltd | Belfast | 2019 |
| Summit of Global Enterprises COM. | London | 2026 |
| Sun Consulting Engineers Limited | Great Yarmouth | 2012 |
| Sunbeam Minerals Limited | Whitby | 2013 |
| Sunda Energy PLC | London | 2004 |
| Sungara Energies Limited | London | 2021 |
| Sunkar Resources Limited | London | 2006 |
| Sunrise Performance Solutions Ltd | Twickenham | 2026 |
| Sunrise Resources PLC | Macclesfield | 2005 |
| Sunterra Ltd | Stanmore | 2019 |
| Supanova Energy Services Limited | Norwich | 2013 |
| Super 6 Services Ltd | Stockport | 2016 |
| Super Engineer Limited | Wimborne | 2011 |
| Super K Enterprises Ltd. | Ilford | 2012 |
| Superior Energy Services Limited | Aberdeen | 2003 |
| Superior-Wild Well Energy Services Limited | Aberdeen | 2009 |