| Compass Management (Harwich) Ltd | Real estate | 2006 |
| Complete Steel Solutions Ltd | Administrative & support | 2016 |
| Connect Without Limits C.I.C. | Health & social care | 2022 |
| Consultancy CAN Limited | Professional & scientific | 2025 |
| Cookies Property Ltd | Real estate | 2023 |
| Cosminvptrans Limited | Wholesale & retail | 2020 |
| Cox's Court Management Company Limited | Households | 2010 |
| Crescent Retouch Limited | Professional & scientific | 2014 |
| CRL Paving Ltd | Wholesale & retail | 2024 |
| Crossreen Limited | Professional & scientific | 2013 |
| Crossreen Properties Limited | Real estate | 2016 |
| CRS Valet Ltd | Administrative & support | 2022 |
| Cruz Underway Limited | Transport & logistics | 2025 |
| Curry & Kebab Kitchen Ltd | Hospitality | 2025 |
| D & M Surveying Services Ltd | Professional & scientific | 2019 |
| D&S Premier Leather Co Ltd | Wholesale & retail | 2023 |
| Daley Wellness and Healthcare Ltd | Health & social care | 2025 |
| DAN Holman Plumbing, Heating & GAS Limited | Construction | 2025 |
| Danlee Building Services Limited | Construction | 2017 |
| Danya Estate Ltd | Real estate | 2025 |
| Dave Soar Rail Limited | Construction | 2015 |
| David Ingram Advisory Ltd | Professional & scientific | 2024 |
| Davies Investment Strategies Ltd | Financial services | 2023 |
| Day 2 Day House Clearance Ltd | Transport & logistics | 2023 |
| Dayjies Ltd | Transport & logistics | 2025 |
| Dbak Ltd | Hospitality | 2022 |
| Deamando Ltd | Hospitality | 2018 |
| Dents Direct Limited | Manufacturing | 2003 |
| Deroy Tool Co.Limited | Manufacturing | 1962 |
| Design UN Limited | Professional & scientific | 2012 |
| DH Truck Diagnostics Ltd | Wholesale & retail | 2020 |
| Digital Darts Online Ltd | Wholesale & retail | 2024 |
| Digital Pathways Mental Health C.I.C. | Health & social care | 2026 |
| Dimac Systems Limited | Manufacturing | 1994 |
| DJH International Limited | Mining & quarrying | 2020 |
| DKP Transport Solutions Limited | Transport & logistics | 2018 |
| DMO Rail Limited | Construction | 2021 |
| Dolphin Sails Limited | Manufacturing | 1991 |
| Dolphin Tensile Awnings Limited | Manufacturing | 2014 |
| Dover Court Ltd | Wholesale & retail | 2023 |
| Dover Court Tandoori Ltd | Hospitality | 2026 |
| Dovercourt Building Contracts Limited | Construction | 2017 |
| Dovercourt DIY Centre Ltd | Wholesale & retail | 2012 |
| Dovercourt Sports and Social Club Limited | Hospitality | 2010 |
| DR R Cole Limited | Health & social care | 2014 |
| DS Towing Ltd | Transport & logistics | 2026 |
| DSV Air & Sea 2018 (UK) Limited | Transport & logistics | 2018 |
| DSV Air & Sea Limited | Transport & logistics | 1995 |
| DSV Commercials Limited | Wholesale & retail | 1999 |
| DSV Contract Logistics Limited | Transport & logistics | 1996 |
| DSV Lead Logistics Limited | Transport & logistics | 1997 |
| DSV Pension Trustees Limited | Extraterritorial | 1991 |
| DSV Real Estate Mercia Park Limited | Transport & logistics | 2024 |
| DSV Real Estate Thrapston Limited | Transport & logistics | 2021 |
| DSV Road Holding Limited | Transport & logistics | 1982 |
| DSV Road Limited | Transport & logistics | 1999 |
| DT Office Wholesale Limited | Wholesale & retail | 2025 |
| Dualities & Developments Ltd | Construction | 2024 |
| Dulai Developments Limited | Construction | 2022 |
| Dulai Investments Limited | Real estate | 2007 |
| Dunninghams Limited | Manufacturing | 2004 |
| Duyar Property Ltd | Real estate | 2025 |
| Dynamix Electrical Limited | Construction | 2021 |
| E-Shell Internet Limited | Other services | 2006 |
| Eagle Bars Ltd | Hospitality | 2017 |
| Eastwood Carpentry Ltd | Manufacturing | 2024 |
| Eastys-Accessories Ltd | Wholesale & retail | 2021 |
| EAT4EIGHT Ltd | Hospitality | 2025 |
| Eaton Clean Limited | Administrative & support | 2019 |
| Edmund XXX | Extraterritorial | 2024 |
| Educational Tours Ltd | Education | 2023 |
| Edwin Lewis Dickinson Limited | Construction | 2018 |
| Edwin Strachan Limited | Agriculture & fishing | 1955 |
| Eggerichs Limited | Construction | 2018 |
| EKA Building Services Ltd | Construction | 2021 |
| Electric Palace (Harwich) Limited | Information & communication | 1982 |
| Electric Storm E-Cigs Ltd | Manufacturing | 2016 |
| Electrozone Management Llco | | 1992 |
| Eler Cleaning Services Limited | Administrative & support | 2017 |
| Elmas Kebab Ltd | Hospitality | 2024 |
| Emitrans Ltd | Transport & logistics | 2021 |
| Emond Family Corporation | Other services | 2019 |
| Empire Party Hire Ltd | Arts & recreation | 2023 |
| Essex Carers Network CIC | Other services | 2011 |
| Essex City Environmental Ltd | Construction | 2024 |
| Essex Roofing Services (2012) Ltd | Construction | 2022 |
| Essexrefurb Limited | Manufacturing | 2014 |
| Euro-Med Trading Limited | Professional & scientific | 2014 |
| EVE Spencer Limited | Arts & recreation | 2011 |
| Eventual Technology Ltd | Information & communication | 2019 |
| Evolve Hair & Beauty Bar Limited | Other services | 2022 |
| Expeditus Invest Ltd | Real estate | 2020 |
| Face and Body Revolution Ltd | Wholesale & retail | 2024 |
| Faces by Maisie Limited | Other services | 2023 |
| Family Activities Community Engagement Support UK (Facesuk) CIC | Health & social care | 2023 |
| Fieldarm Holdings Limited | Financial services | 2020 |
| Fieldarm Limited | Agriculture & fishing | 2008 |
| Financial Operations Limited | Professional & scientific | 2018 |
| Financial Productions Limited | Professional & scientific | 2014 |
| First in Electrical Services Ltd | Construction | 2024 |