| S M B Wind Service Ltd | Manufacturing | 2024 |
| S Mccormick Investments Ltd | Real estate | 2017 |
| S Mogg Plumbing and Heating Limited | Construction | 2011 |
| S P Manufacturing Company Limited | Manufacturing | 2010 |
| S Property 4U Ltd | Real estate | 2024 |
| S Rawlins Double Glazing Limited | Construction | 2002 |
| S S Medical Limited | Health & social care | 2015 |
| S V Design Engineering Ltd | Professional & scientific | 2011 |
| S&Cb Training Ltd | Education | 2020 |
| S&H Desert and Pizza Ltd | Hospitality | 2025 |
| S&J Enterprize Limited | Real estate | 2025 |
| S&R Property and Technical Limited | Construction | 2018 |
| S&S Properties (Lincs) Ltd | Construction | 2025 |
| S. Cropley & Co. Limited | Wholesale & retail | 1982 |
| S.A.M Electrical Ltd | Construction | 2017 |
| S.A.Mossop(Farms)Limited | Agriculture & fishing | 1952 |
| S.Brown Joinery Ltd | Construction | 2022 |
| S.C Engineering Consultants Ltd | Professional & scientific | 2018 |
| S.C.G Construction Lincs Ltd | Construction | 2020 |
| S.H. Somerscales Limited | Agriculture & fishing | 1975 |
| S.Halgarth Limited | Agriculture & fishing | 1954 |
| S.J. Margetts Limited | Administrative & support | 1996 |
| S.P.T Lincolnshire and Yorkshire Ltd | Arts & recreation | 2018 |
| S.R. Electrical Wholesalers Limited | Wholesale & retail | 2009 |
| S.T.L. Properties Limited | Construction | 2005 |
| S.Y.M Services Limited | Health & social care | 2023 |
| S4 Ventures Ltd | Real estate | 2025 |
| Sade Estates Ltd | Real estate | 2024 |
| Safe Systems (UK) Ltd | Professional & scientific | 2011 |
| Safe-Mech PG Consulting Ltd | Professional & scientific | 2020 |
| Safelec Services Limited | Construction | 2004 |
| Safety & Management Ltd | Professional & scientific | 2020 |
| Sage Catering Limited | Transport & logistics | 2002 |
| Sage Diagnostics Ltd | Health & social care | 2026 |
| SAI Dutt Ltd | Wholesale & retail | 2012 |
| Saifety Solutions Limited | Administrative & support | 2024 |
| Sajtrans Ltd | Transport & logistics | 2019 |
| Sakina Food Ltd | Hospitality | 2020 |
| SAL Commercials Limited | Professional & scientific | 2000 |
| Salamander Property Developments Ltd | Real estate | 2021 |
| Salamander Property Maintenance Limited | Construction | 2011 |
| Salenexus Ltd | Wholesale & retail | 2024 |
| Sally's Boutique Ltd | Manufacturing | 2022 |
| Sally-Bobo Engineering Limited | Professional & scientific | 2020 |
| Salocan Limited | Hospitality | 2018 |
| Salon Fifty 7 Ltd | Other services | 2025 |
| SALON19 (Broxbourne) Ltd | Other services | 2019 |
| Salters in Transit Ltd | Transport & logistics | 2016 |
| Saltfleetby Fisheries Limited | Agriculture & fishing | 2002 |
| SAM Coulbeck (Refrigeration Rentals) Limited | Manufacturing | 1978 |
| SAM Coulbeck Limited | Financial services | 1949 |
| Sam's 1 CUT Ltd | Other services | 2025 |
| Sam's Cakes & Bakes Limited | Hospitality | 2023 |
| Sama Medical Services Limited | Health & social care | 2020 |
| Samantha Lims Ltd | Information & communication | 2026 |
| Samantha Victoria Aesthetics Limited | Other services | 2021 |
| Same Day Delivery Limited | Wholesale & retail | 2011 |
| Sami Laker Aesthetics Limited | Other services | 2023 |
| Sami Trans Ltd | Transport & logistics | 2026 |
| Sampac Limited | Manufacturing | 2012 |
| Sample Scents Ltd | Wholesale & retail | 2024 |
| Samskip Limited | Transport & logistics | 1995 |
| Samuel Estera Limited | Transport & logistics | 2025 |
| Samuele Sois Engineering Consulting Limited | Administrative & support | 2014 |
| Samurai Hearts Limited | Other services | 2018 |
| Sanctum Asset Management Ltd | Professional & scientific | 2022 |
| Sand and Powder Ltd | Manufacturing | 2026 |
| Sandcastles Gifts Limited | Wholesale & retail | 2020 |
| Sanders Pearson Limited | Administrative & support | 2002 |
| Sanderson Executive Security Ltd | Administrative & support | 2025 |
| Sandu Ionut Transport Ltd | Transport & logistics | 2026 |
| Sandwich Lord Ltd. | Hospitality | 2026 |
| Sandy Seagull Limited | Hospitality | 2024 |
| Sanfish Brand Limited | | 1982 |
| Sano Life Limited | Health & social care | 2019 |
| Sanscoe Kennels Limited | Professional & scientific | 2003 |
| Sanskrithi Ltd | Real estate | 2021 |
| Santon Solar Limited | Real estate | 2021 |
| Sapa Ltd Ltd | Construction | 2020 |
| Sapphire & Co UK Ltd | Wholesale & retail | 2017 |
| Sara Hudson Services Limited | Other services | 2025 |
| Sarah Anderson Design Limited | Administrative & support | 2001 |
| Sarah Jane Watson International Ltd | Other services | 2018 |
| Sarahs Childminding Grimsby Limited | Education | 2013 |
| Sargent's Plumbing & Heating Ltd | Construction | 2021 |
| Sarpro Care Limited | Health & social care | 2014 |
| Sasapu Ltd | Health & social care | 2013 |
| Sasdav Limited | Hospitality | 2019 |
| Sasha Health Limited | Health & social care | 2018 |
| Sata Bricklaying. Ltd | Construction | 2019 |
| Satellite Architects Limited | Professional & scientific | 1994 |
| Satori 21 Limited | Professional & scientific | 2017 |
| Satoth Limited | Manufacturing | 2022 |
| Saturn Electrical Services Limited | Construction | 2010 |
| Savannah Audio Limited | Arts & recreation | 2003 |
| Savannahmedic Ltd | Health & social care | 2020 |
| Save on Sofas and Beds Limited | Wholesale & retail | 2019 |
| Sawyer Property Services Ltd | Real estate | 2023 |
| Saxon Park at Branston Management Company Limited | Professional & scientific | 2020 |
| Saxtons Plumbing & Heating Limited | Construction | 2012 |