| Sherlock Industrial Heating Ltd | Manufacturing | 2012 |
| Shine More Exterior Cleaning Limited | Other services | 2026 |
| Ship Inn 2002 Limited | Hospitality | 2002 |
| Shires Life Limited | Construction | 2020 |
| Shop Here Limited | Wholesale & retail | 2018 |
| SHOPANDENJOY111 Limited | Wholesale & retail | 2016 |
| Shot on Rate Ltd | Manufacturing | 2026 |
| Showerstoyou Limited | Wholesale & retail | 2008 |
| Shred Leisure Ltd | Construction | 2016 |
| Shrijana Limited | Wholesale & retail | 2026 |
| Shuffle Innovations Limited | Information & communication | 2012 |
| Shya's News Ltd | Wholesale & retail | 2015 |
| Sialiona Ltd | Wholesale & retail | 2021 |
| Siana Transport Ltd | Transport & logistics | 2025 |
| Sibtain-Zahra Limited | Health & social care | 2013 |
| Sicily Pizzeria Limited | Hospitality | 2003 |
| Sicily Takeaway Ltd | Hospitality | 2026 |
| Sidhu and Sheikh Ltd | Real estate | 2023 |
| SIE Prestige Ltd | Administrative & support | 2026 |
| Sigma Office Solutions Limited | Administrative & support | 2003 |
| Sign & Print NE Lincs Ltd | Manufacturing | 2020 |
| Signal Box Way Community Limited | Extraterritorial | 2024 |
| Signature Fitness GY Limited | Arts & recreation | 2019 |
| Signcomm Limited | Professional & scientific | 1995 |
| Signology (Grimsby) Ltd | Professional & scientific | 2006 |
| Silowhip Ltd | Administrative & support | 2017 |
| Silver Eagle Solutions Ltd | Information & communication | 2008 |
| Silver Pharma Ltd | Health & social care | 2016 |
| Simon B Ltd | Transport & logistics | 2024 |
| Simon Caine Limited | Professional & scientific | 2024 |
| Simon Dobson Tree Services Limited | Administrative & support | 2019 |
| Simon Hubert Bathrooms Ltd | Construction | 2014 |
| Simon Jowitt Consultancy Limited | Arts & recreation | 2019 |
| Simon Mumby Building Limited | Construction | 2019 |
| Simon Peart Consulting Limited | Information & communication | 2006 |
| Simon T Wood IT Consultancy Limited | Information & communication | 2013 |
| Simon Thorpe Motor Services Limited | Wholesale & retail | 2010 |
| Simons Fish Limited | Hospitality | 2003 |
| Simons Instrument Electrical Metering Services Ltd | Construction | 2024 |
| Simplex Safety Solutions Limited | Professional & scientific | 2019 |
| Simpli Print Ltd | Manufacturing | 2018 |
| Simply Delicious TOO Ltd | Hospitality | 2015 |
| Simply Divine Medical Aesthetics Limited | Other services | 2021 |
| Simply Refreshed Grimsby Limited | Water & waste | 2021 |
| Simsem Ltd | Real estate | 2025 |
| SINEMA101 Ltd | Extraterritorial | 2018 |
| Sipco Pharma UK Ltd | Wholesale & retail | 2013 |
| Sirfy AZ Location Services Ltd | Administrative & support | 2023 |
| Siri 23 Ltd | Health & social care | 2014 |
| Siriba Ltd. | Financial services | 2017 |
| Sirius Demolition Experts Limited | Construction | 2026 |
| Site Commissioning Consultants Limited | Professional & scientific | 2025 |
| Site Instrument Limited | Administrative & support | 2020 |
| Sitemore Engineering Limited | Professional & scientific | 2015 |
| SIX Towns Contracting Ltd | Administrative & support | 2013 |
| Sixql Ltd | Information & communication | 2025 |
| Sizzling WOK Ltd | Hospitality | 2026 |
| SJ Burr Ltd | Construction | 2023 |
| SJ Nelson Brickwork Ltd | Construction | 2025 |
| SJ Rotating Equipment Services Limited | Manufacturing | 2018 |
| SJC (Lincoln) Ltd | Professional & scientific | 2020 |
| SJF Contracting Services Limited | Agriculture & fishing | 2008 |
| Sjhj Ltd | Wholesale & retail | 2022 |
| SJM Brickwork Ltd | Construction | 2020 |
| Sjmc Groundworks Limited | Construction | 2019 |
| SJP Enterprises Limited | Other services | 2014 |
| Sk&O Limited | Professional & scientific | 2025 |
| Skillspark Digital Ltd | Professional & scientific | 2025 |
| Skillzspar Limited | Wholesale & retail | 2018 |
| Skin Factory Limited | Other services | 2003 |
| Skin Luxe Aesthetics Ltd | Other services | 2019 |
| Skipper's Pet Products Limited | Manufacturing | 2013 |
| SKV Installations Limited | Construction | 2020 |
| Sky Logistics Limited | Wholesale & retail | 2005 |
| Sky Nail Grimsby Ltd | Other services | 2020 |
| Skyfall GY Limited | Households | 2024 |
| Skyfx Ltd | Information & communication | 2018 |
| Skyhigh Supplies Ltd | Manufacturing | 2020 |
| Skysocials Ltd | Professional & scientific | 2025 |
| Skyward Associates Limited | Professional & scientific | 1997 |
| SL Mortimer Properties Ltd | Real estate | 2025 |
| SL100 Limited | Administrative & support | 2007 |
| SL200 Limited | Extraterritorial | 2016 |
| Slab Property Ltd | Real estate | 2024 |
| Slade's Wonder Emporium Ltd | Wholesale & retail | 2022 |
| Slavika Groceries Ltd | Wholesale & retail | 2019 |
| SLD Property Holdings Ltd | Real estate | 2019 |
| Sleepbox Ltd | Hospitality | 2011 |
| Sleeping Beauty Ltd | Arts & recreation | 2025 |
| Slice Masters Ltd | Hospitality | 2021 |
| Slimxstudio Ltd | Other services | 2025 |
| Slippery When WET Limited | Manufacturing | 2003 |
| SLM (07675473) Limited | Transport & logistics | 2011 |
| SLM29 Limited | Health & social care | 2022 |
| Slmacl Limited | Health & social care | 2015 |
| Slush Bar (Mablethorpe) Limited | Wholesale & retail | 2017 |
| SM Powell (Grimsby) Limited | Administrative & support | 2026 |
| SM Powell Limited | Administrative & support | 2018 |
| SM Property Cleethorpes Limited | Real estate | 2018 |
| SMA Medical Services Ltd | Health & social care | 2026 |