| Stannworks Engineering Ltd | Construction | 2021 |
| Stannworks Properties Ltd | Real estate | 2023 |
| Star Cabs Limited | Transport & logistics | 2011 |
| Star Minibuses Limited | Transport & logistics | 2011 |
| Starkey Cleaning Company Limited | Administrative & support | 2019 |
| Starling Nest Limited | Real estate | 2026 |
| Stars N Jars (Haverhill) Ltd | Wholesale & retail | 2019 |
| Stars N Jars Tech Ltd | Information & communication | 2020 |
| Steelbuild Developments Ltd | Construction | 2026 |
| Stephen Partridge Consultancy Ltd | Professional & scientific | 2023 |
| Steve French Limited | Construction | 2018 |
| Stewart Taylor Mower Services Limited | Manufacturing | 2010 |
| Stour Valley Trading Ltd | Arts & recreation | 2011 |
| Stratton Construction Limited | Real estate | 2024 |
| Streams Group Limited | Wholesale & retail | 2026 |
| Street Cafe Limited | Hospitality | 2010 |
| Street Cafe Property Ltd | Real estate | 2019 |
| Street Smart Security & AV Ltd | Financial services | 2019 |
| Sturmer Garage Ltd | Wholesale & retail | 2021 |
| Stylize Digital Artwork Ltd. | Administrative & support | 2002 |
| Stylize Display Graphics Limited | Professional & scientific | 2005 |
| Suffolk and Essex Construction Limited | Construction | 2000 |
| Suffolk and Essex Joinery Holdings Limited | Financial services | 2024 |
| Suffolk and Essex Joinery Limited | Manufacturing | 1998 |
| Suffolk Asbestos Ltd | Water & waste | 2022 |
| Suffolk Braunton Property Ltd | Real estate | 2024 |
| Suffolk Clutch Centre Ltd | Wholesale & retail | 2025 |
| Suffolk Hospitality Ltd | Hospitality | 2024 |
| Suffolk Membership Ltd | Other services | 2026 |
| Suffolk N U Beauty Limited | Other services | 2021 |
| Suffolk N U Tanning Limited | Other services | 2019 |
| Sugaring London Ltd | Other services | 2017 |
| Sunflower Send Hub Ltd | Education | 2025 |
| Supreme Work Surfaces Ltd | Construction | 2025 |
| Sureservice Limited | Manufacturing | 2012 |
| Sweet Finance Ltd | Professional & scientific | 2025 |
| Swinney Renovations Ltd | Real estate | 2021 |
| Sybilla Consulting Limited | Information & communication | 2002 |
| Sygma Fire Services Ltd | Administrative & support | 2009 |
| Sylvan Ferns Ltd | Real estate | 2025 |
| Symtech Plumbing & Heating Ltd | Construction | 2013 |
| Synergykey Limited | Information & communication | 2000 |
| Synergykey Property Limited | Real estate | 2013 |
| T H Q Tape and Jointing Limited | Construction | 2023 |
| T J Archer Ltd | Construction | 2018 |
| T M G Builders Limited | Construction | 1999 |
| T&M Professional Cleaning Ltd | Extraterritorial | 2025 |
| T.J Fenton Ltd | Construction | 2018 |
| Taqueria LA Gringa Ltd | Hospitality | 2023 |
| Tart Products Limited | Wholesale & retail | 2022 |
| TAU Management Services Limited | Extraterritorial | 2024 |
| Taxi 2 Day Ltd | Transport & logistics | 2023 |
| Taxi Vibe Limited | Transport & logistics | 2023 |
| Taylor's Foundry Limited | Manufacturing | 1949 |
| Taylors Foundry Motor Sport Limited | Manufacturing | 1996 |
| Tayvin 91 Limited | Agriculture & fishing | 1997 |
| TCS Medicare Ltd | Administrative & support | 2015 |
| TDM Associates Limited | Professional & scientific | 2014 |
| TDR Car Repairs Limited | Wholesale & retail | 2025 |
| Teal and Tweed Ltd | Manufacturing | 2024 |
| Tech Talent Partners Limited | Administrative & support | 2023 |
| Technarrate Limited | Extraterritorial | 2024 |
| Technic Motors Limited | Wholesale & retail | 2003 |
| Teknique Converters Ltd | Manufacturing | 2021 |
| Teletherm Limited | Professional & scientific | 2007 |
| Temple Engineering Limited | Real estate | 2009 |
| Tempower Limited | Construction | 2007 |
| Tempower Services Limited | Extraterritorial | 2010 |
| TEN10 Properties Limited | Real estate | 2025 |
| Terence Barker Limited | Manufacturing | 1970 |
| TES Holdings Limited | Water & waste | 2019 |
| TFC Electrical Ltd | Construction | 2021 |
| Thai Street Cafe Limited | Hospitality | 2009 |
| THE Agricultural Parts Company Ltd | Wholesale & retail | 2021 |
| THE Almshouses 1618 Limited | Real estate | 2013 |
| THE Audiology Expert Limited | Wholesale & retail | 2021 |
| THE Bottle MEN Ltd | Other services | 2021 |
| THE Box Contracts Ltd | Construction | 2019 |
| THE Broker (Haverhill) Ltd | Financial services | 2021 |
| THE Bull (2017) Ltd | Hospitality | 2017 |
| THE Cambridge Asset Investment Ltd | Real estate | 2022 |
| THE Cambridge Biryani Company Ltd | Hospitality | 2024 |
| THE Cedars (Haverhill) Management Company Limited | Households | 2001 |
| THE Centre Training Workshops Ltd | Health & social care | 2025 |
| THE Chocolate Lady Limited | Wholesale & retail | 2005 |
| THE Community Schools CIC | Education | 2023 |
| THE Dog and Collar Limited | Wholesale & retail | 2025 |
| THE Fourth Wall Performing Arts Limited | Education | 2013 |
| THE FOX and Hounds Bumpstead Ltd | Hospitality | 2019 |
| THE Good Web Guide Limited | Arts & recreation | 1999 |
| THE Haverhill Bookkeeper Limited | Administrative & support | 2008 |
| THE Holistic Carer Limited | Health & social care | 2024 |
| THE Hoveraid Trust | Manufacturing | 1991 |
| THE Hunter Gallery Limited | Wholesale & retail | 2015 |
| THE Little Nephew&Nieces Transport Limited | Transport & logistics | 2026 |
| THE Mortgage Centre (Haverhill) Limited | Financial services | 2023 |
| THE New Nigerian Limited | Manufacturing | 2020 |
| THE Old School (Kedington) Management Company Limited | Households | 2006 |
| THE Property People Ltd | Real estate | 2018 |
| THE Risk of YOU Limited | Professional & scientific | 2020 |