| Spectrum GEO Limited | Weybridge | 1986 |
| Speedwell Energy Limited | Aberdeen | 2012 |
| Spencer Metals Limited | Elland | 2024 |
| Spencer Offshore Limited | Fleetwood | 2018 |
| Spencer Petroleum Consulting Ltd | Guildford | 2022 |
| Spex Engineering Limited | Aberdeen | 2010 |
| Spey Valley Mining Ltd | Glasgow | 2022 |
| Speyside Sand & Gravel Quarries Limited | Glasgow | 1983 |
| SPF Inspection Ltd | Seaham | 2020 |
| Sphera Services Ltd | Shetland | 2025 |
| Sphere-Alfa Limited | York | 2004 |
| Spin Mining and Metals Limited | London | 2020 |
| Spindeep Limited | Berks | 1990 |
| Spineores Resources Limited | Preston | 2018 |
| Spinnaker Energy Limited | Edinburgh | 2010 |
| Spiral Subsea Ltd | Norwich | 2020 |
| Spirit Energy North Sea Limited | Windsor | 2002 |
| Spirit Energy North Sea OIL Limited | Aberdeen | 2000 |
| Spirit Energy Production UK Limited | Windsor | 1995 |
| Spirit Energy Resources Limited | Windsor | 1993 |
| Spirit Energy Southern North Sea Limited | Windsor | 2006 |
| Spirit Europe Limited | Windsor | 2004 |
| Spirit North Sea GAS Limited | Aberdeen | 1998 |
| Spirit Resources (Armada) Limited | Windsor | 2001 |
| SPM OIL & GAS Scotland Limited | Portlethen | 1991 |
| Spoton Energy UK Limited | Hemel Hempstead | 2021 |
| Spraycrete Limited | Caernarfon | 2025 |
| Springfield Farm Limited | Potterspury | 1987 |
| Springhill Stone Limited | Halifax | 2005 |
| Springwood Mining UK Services | Preston | 2015 |
| SPS ROV Limited | St Asaph | 2023 |
| Spsi (GBR) Limited | Bishops Castle | 2022 |
| SR Geoscience Limited | Glasgow | 2018 |
| SR Production Engineering Limited | Aberdeen | 2016 |
| Sramd Limited | Whitby | 2012 |
| SRG Wellservices Limited | Montrose | 2004 |
| SRK Inspections Ltd | Halifax | 2018 |
| SRP Mining Limited | Colwyn Bay | 2021 |
| Srss Offshore Ltd | Hull | 2016 |
| SS 3D Visualisation Limited | Dundee | 2017 |
| SS Duncan Ltd | Kintore | 2011 |
| Ssjp Engineering Ltd | Middlesbrough | 2020 |
| Ssrr Industries Limited | Elgin | 2025 |
| ST Anthonys House Ltd | London | 2022 |
| ST Stephen's GAS Limited | Llandysul | 2010 |
| ST. Catherines Flint Products Limited | Dorchester | 2002 |
| Stacey Crushing & Plant Hire Limited | Matlock | 2023 |
| Staffordshire Campers Ltd | Wolverhampton | 2013 |
| Staffordshire Stone Production Ltd | Stoke On Trent | 2013 |
| Stag Energy Limited | Colwick Nottingham | 2000 |
| Stainby Stone Ltd. | Grantham | 2016 |
| Stainton Quarry Ltd | Darlington | 2008 |
| Stalactite Natural Stone Limited | London | 2025 |
| Stalbridge Quarries Limited | Sturminster Newton | 1998 |
| Stamford Commodities & Resources Group Ltd | Cardiff | 2019 |
| Stancliffe Stone Co. Limited | Elland | 1989 |
| Stancliffe Stone Company Limited | Belper | 2023 |
| Standard Capital Holdings Limited | Brighton | 2019 |
| Standard Resources Limited | London | 2014 |
| Standrews Inspection Services Limited | St. Andrews | 2025 |
| Staneyhill Quarry Limited | Forfar | 2012 |
| Stanley Bell and Sons Limited | Co Tyrone | 2006 |
| Stanley Emerson & Sons Limited | Craigavon | 1979 |
| Stanley Mining Ltd | London | 2020 |
| Stannum Resources Limited | Leeds | 2010 |
| Stapleton International Emea Limited | Sunderland | 2014 |
| Star Energy Group PLC | Lincoln | 2003 |
| Star Energy Limited | Lincoln | 1999 |
| Star Energy Weald Basin Limited | Lincoln | 2007 |
| Starlight Gold International Ltd | Burry Port | 2024 |
| Starmax Systems Limited | Carshalton | 1999 |
| State of Israel GUO Feng Chemical Industry Group Co., Ltd | West Midlands | 2023 |
| Stathis Offshore Limited | Aberdeen | 2006 |
| Stathis Property Limited | Manchester | 2016 |
| Stats (UK) Ltd. | Aberdeen | 1998 |
| Stavrin Metodiev Ltd | Thornton Heath | 2025 |
| Stedetradsteel. Ltd | Salford | 2005 |
| Steed (UK) Limited | Norwich | 2007 |
| Stellar Diamonds Limited | London | 2005 |
| Stellar Energy Advisors Company Limited | Glasgow | 2025 |
| Stellar Energy Advisors Group Limited | Barnet | 2015 |
| Stena Carron Drilling Limited | London | 2015 |
| Stena DON Drilling Limited | London | 2018 |
| Stena Drilling (Holdings) Limited | London | 1990 |
| Stena Drilling HR Limited | London | 2006 |
| Stena Drilling Limited | London | 1899 |
| Stena Drillmax Ice Limited | London | 2011 |
| Stena Evolution Drilling Limited | London | 2022 |
| Stena Evolve Limited | London | 2021 |
| Stena Forth Drilling Limited | London | 2011 |
| Stena HSD Limited | London | 1993 |
| Stena Oilfield Services Limited | London | 2011 |
| Stena Spey Chartering Limited | London | 2012 |
| Stena Spey Drilling Limited | London | 1990 |
| Stena Spey Services Limited | London | 2011 |
| Stenloyal Limited | Aberdeen | 1992 |
| Stenmor Resources Ltd | Launceston | 2025 |
| Stepeum Ltd | Manchester | 2024 |
| Stephen Kane Limited | Dundee | 2012 |
| Stephenson Contracts Ltd | Lincoln | 2025 |