| Heleus Limited | Administrative & support | 2012 |
| Helios Roofing Ltd | Construction | 2025 |
| Henpac Ltd | Administrative & support | 2024 |
| Hotel Catifornia Limited | Other services | 2015 |
| Howarth Winterbrook (Sales) Limited | Manufacturing | 1978 |
| Howarth Winterbrook Limited | Manufacturing | 2010 |
| IAN Isaac Associates Limited | Health & social care | 2011 |
| Istanbul Barber EN Ltd | Other services | 2023 |
| J Wright Training Services Ltd | Other services | 2019 |
| J&R Plastering Services Ltd | Construction | 2022 |
| J.Ward & Son(Farms) | Agriculture & fishing | 1949 |
| JAJ (Ipswich) Limited | Real estate | 2004 |
| JS2 Limited | Professional & scientific | 1997 |
| JTG Property Renovations Ltd | Construction | 2026 |
| K2 Plant Hire Limited | Manufacturing | 1995 |
| Karan D UK Ltd | Real estate | 2020 |
| Kelton Construction Limited | Construction | 2023 |
| Kirby DIG Limited | Other services | 1999 |
| Kirpi Ltd | Hospitality | 2025 |
| Kyranbarnett Ltd | Professional & scientific | 2026 |
| L S Easton Limited | Manufacturing | 2022 |
| L.F.Geater and Sons Limited | Wholesale & retail | 1960 |
| Lambs Optical Services Limited | Health & social care | 2011 |
| Laura Thomson Ltd | Health & social care | 2025 |
| Lawncourt Harvest Limited | Manufacturing | 2000 |
| LB Wills & Probate (Norfolk) Ltd | Professional & scientific | 2019 |
| Leiston Car Body Repair Centre Ltd | Wholesale & retail | 2025 |
| Leiston Dental Care Ltd | Health & social care | 2021 |
| Leiston Joinery Ltd | Manufacturing | 2020 |
| Leiston Newsagent Ltd | Wholesale & retail | 2012 |
| Leiston Press Ltd | Manufacturing | 2011 |
| Leiston Town Athletics Association Incorporating Leiston Football Club C.I.C. | Arts & recreation | 2023 |
| LEO Feast Ltd | Hospitality | 2025 |
| Lexington Access Limited | Information & communication | 2026 |
| Linkone International Holdings Limited | Manufacturing | 2025 |
| Livelarge Developments Limited | Construction | 2007 |
| Lobsta Limited | Wholesale & retail | 2002 |
| Loyal Care Limited | Health & social care | 2019 |
| Lukesvale Property Ltd | Real estate | 2023 |
| Made at NO.2 Ltd | Manufacturing | 2023 |
| Mandor House Limited | Real estate | 2001 |
| Manor Place (Leiston) Management Company Ltd | Households | 2019 |
| Marshall & Lilley Limited | Other services | 2008 |
| Maryada Limited | Wholesale & retail | 2025 |
| Mason & Grey Limited | Real estate | 2018 |
| MCM6 Ltd | Construction | 2025 |
| Melton Tyre Properties Limited | Real estate | 2004 |
| Mint Fitness Aldeburgh Limited | Arts & recreation | 2016 |
| Mint Fitness Ltd | Arts & recreation | 2015 |
| Mobam Construction Limited | Wholesale & retail | 2026 |
| Moontree Project Consultancy Ltd | Information & communication | 2026 |
| Moor Farms (Middleton) Limited | Agriculture & fishing | 1963 |
| Morphey Plastering Contractors Ltd | Construction | 2017 |
| Mossy's Original Ltd | Manufacturing | 2015 |
| MR Pickles Limited | Arts & recreation | 2018 |
| MSS Properties EN Ltd | Real estate | 2020 |
| Newson & Driver Limited | Construction | 2008 |
| Noodling Ltd | Professional & scientific | 2026 |
| North Laundry (Aldeburgh) Limited(The) | Real estate | 1938 |
| Nulla Limited | Extraterritorial | 2018 |
| Oaks Court (Thorpeness) Management Company Ltd | Households | 2018 |
| Overed Ltd | Real estate | 2022 |
| Painting Pixels Ltd | Arts & recreation | 2010 |
| PC Property Services Ltd | Households | 2025 |
| Pete's Pizzas Ltd | Hospitality | 2023 |
| Pewley Heights Residents Company Limited | Households | 2006 |
| Phillips Strategic Engineering Ltd | Professional & scientific | 2025 |
| Pinnet Infotech Limited | Information & communication | 2021 |
| PJM Plumbing Ltd | Construction | 2016 |
| Pro Corda Trust | Education | 2006 |
| Pro Corda Ventures Limited | Hospitality | 1993 |
| Purehaven Limited | Real estate | 1982 |
| Qdex Limited | Wholesale & retail | 2002 |
| R.S.C. Landscapes Ltd | Administrative & support | 2007 |
| RDJ Mitchell Ltd | Professional & scientific | 2024 |
| River Care Suffolk Ltd | Households | 2025 |
| Robbie Dixon Electrical Services Ltd | Construction | 2023 |
| Rowes Real Estate Ltd | Real estate | 2026 |
| Sacantics Clothing Limited | Wholesale & retail | 2025 |
| Samphire Recruitment Ltd | Administrative & support | 2022 |
| Scoops by Tarnya Ltd | Wholesale & retail | 2026 |
| Seax Vapourium Ltd | Wholesale & retail | 2015 |
| Shaun's Auto Repairs Ltd | Wholesale & retail | 2024 |
| Shine and Stay Cleaning Ltd | Administrative & support | 2025 |
| Shine and Stay Commercial Cleaning Ltd | Administrative & support | 2026 |
| Sizewell Hall Limited | Hospitality | 1975 |
| Sizewell Tea Ltd | Hospitality | 2025 |
| Somfolk Limited | Professional & scientific | 2022 |
| South Bank Management Company Limited | Households | 1996 |
| Southwold Sausage Walk Ltd | Wholesale & retail | 2025 |
| SPC Plumbing & Heating (Suffolk) Ltd | Construction | 2023 |
| Steven RAE Ltd | Transport & logistics | 2011 |
| Stonecrest Developments Ltd | Construction | 2026 |
| Suffolk Land Ltd | Real estate | 2023 |
| Suffolk Restaurants Ltd | Hospitality | 2021 |
| T P LUU Limited | Hospitality | 2016 |
| TD Construction (Suffolk) Limited | Construction | 2026 |
| Technical Delivery Consulting Limited | Professional & scientific | 2022 |
| THE Administ Solutions Ltd | Administrative & support | 2025 |
| THE Band Hall CIC | Other services | 2023 |