| 3C Electrical Ltd | Construction | 2016 |
| 3D Facades Ltd | Construction | 2022 |
| 3D Fittings Limited | Manufacturing | 2008 |
| 3DOODLE Ltd | Manufacturing | 2024 |
| 3FLEX Ltd | Wholesale & retail | 2022 |
| 3GEN Moving Group Ltd | Transport & logistics | 2025 |
| 3HA Limited | Administrative & support | 2013 |
| 3HA Properties Ltd | Real estate | 2022 |
| 3HHH Care Limited | Health & social care | 2025 |
| 3I Trading Limited | Hospitality | 2025 |
| 3WISHES Theatre CIC | Arts & recreation | 2024 |
| 4 Mika Co. Limited | Arts & recreation | 2012 |
| 4 Seasons Landscaping Services Ltd | Administrative & support | 2021 |
| 4-11 Consultants Limited | Information & communication | 2002 |
| 404 Films Ltd | Information & communication | 2026 |
| 41 Rosslyn Hill Property Management Limited | Extraterritorial | 1998 |
| 41 Wellesley Road RTM Company Limited | Households | 2013 |
| 42 Elmbourne Manor Limited | Households | 2007 |
| 42/43 Hythe Hill Freehold Limited | Households | 2007 |
| 43 Constantine Road (Freehold) Limited | Households | 2023 |
| 43 ST. Mary's Road Limited | Hospitality | 1994 |
| 43 West Avenue Limited | Households | 2007 |
| 46-48 Maigold Avenue Management Company Limited | Real estate | 2024 |
| 48-54 Cleveland Close RTM Company Limited | Households | 2019 |
| 4BEES Miracles Services Ltd | Other services | 2016 |
| 4D Education Limited | Education | 2022 |
| 4PL Central Station Ltd | Transport & logistics | 2002 |
| 4PL Central Station UK Ltd | Transport & logistics | 2003 |
| 4SITE Ceramics Limited | Construction | 2019 |
| 4TH Element Consulting Limited | Information & communication | 2014 |
| 4TK Gaming Limited | Wholesale & retail | 2005 |
| 4W Building Services Limited | Construction | 2017 |
| 4YAKHA Brothers Ltd | Manufacturing | 2025 |
| 5 & 6 Vint Crescent Colchester Ltd | Households | 2012 |
| 5 - 13 Moreland Court RTM Company Limited | Households | 2023 |
| 5 Nightingale Court Colchester Limited | Households | 2000 |
| 5 Stradbroke Road Freehold Company Limited | Households | 2025 |
| 55 Fourth Avenue Property Management Company Limited | Households | 2007 |
| 56 Cannon Street Road Freehold Limited | Households | 2013 |
| 5K Consultancy Limited | Professional & scientific | 2019 |
| 5S Property Investment Company Ltd | Real estate | 2020 |
| 6 Nightingale Court Colchester Limited | Households | 2000 |
| 6 Sided Dice Ltd | Professional & scientific | 2024 |
| 609B Kingsway Square Ltd | Real estate | 2024 |
| 60KL Ltd | Professional & scientific | 2017 |
| 61 New Road LLP | | 2020 |
| 64 Barons Court Road Freehold Limited | Real estate | 2002 |
| 658 Limited | Information & communication | 2018 |
| 666 Automotive Limited | Wholesale & retail | 2025 |
| 67 Comyn Road Residents 2022 Limited | Households | 2022 |
| 67 Endymion Road (Freehold) Limited | Hospitality | 2012 |
| 6791 Engineering Services Limited | Professional & scientific | 2017 |
| 6TWO1 Trading Limited | Wholesale & retail | 2015 |
| 7 Spice Restaurant Ltd | Hospitality | 2024 |
| 70-74 High Street Aldeburgh Limited | Households | 2008 |
| 71C Ltd | Construction | 2022 |
| 76 Amberley Road Limited | Financial services | 2015 |
| 7ROADLIGHT CIC | Administrative & support | 2019 |
| 8 Ball CAF Ltd | Manufacturing | 2023 |
| 8 Rushmore Road Management Limited | Households | 1996 |
| 8 the Avenue Colchester Limited | Households | 2006 |
| 8010 Media Ltd | Information & communication | 2023 |
| 81 Harwood Road Limited | Real estate | 2000 |
| 81 Haven Road Limited | Households | 2007 |
| 818 Manchester Ltd | Real estate | 2024 |
| 82 Amhurst Park RTM Company Ltd | Households | 2020 |
| 83 L&D Ltd | Professional & scientific | 2015 |
| 882 London Road LOS (Freehold) Limited | Households | 2019 |
| 888 Club Holdings Ltd | Professional & scientific | 2026 |
| 9 Eggs Limited | Information & communication | 2008 |
| 9-24 Place Farm Court RTM Company Limited | Households | 2025 |
| 90 Minutes Services Ltd | Hospitality | 2024 |
| 96 QR Felixstowe Management Co Limited | Households | 2021 |
| 96-98 Felixstowe Road (Ipswich) Management Company Limited | Households | 2004 |
| 9MSS UK Ltd | Professional & scientific | 2017 |
| 9UP Studio Ltd | Information & communication | 2023 |
| A & D Contracting Ltd | Administrative & support | 2020 |
| A & DP Limited | Professional & scientific | 2005 |
| A & G Farms LLP | | 2009 |
| A & G Property Lets Ltd | Households | 2018 |
| A & I Fisher Limited | Wholesale & retail | 1986 |
| A & J Acquisition Ltd | Real estate | 2020 |
| A & K Construction Limited | Construction | 2023 |
| A & M Boiler Services Limited | Administrative & support | 1997 |
| A & M Pizza Box Ltd | Hospitality | 2018 |
| A & P Paving Ltd | Construction | 2018 |
| A & R Blinds Ltd | Construction | 2025 |
| A & S Advisory Ltd | Hospitality | 2025 |
| A & S Aggregates Ltd | Administrative & support | 1990 |
| A & S Plumbing & Heating Services Ltd | Construction | 2006 |
| A & V Barbers Ltd | Other services | 2020 |
| A 2 B Distribution Limited | Extraterritorial | 2020 |
| A a and T (Mersea) Ltd | Professional & scientific | 2025 |
| A a and T (WM) Ltd | Professional & scientific | 2022 |
| A a Turner Tankers Ltd | Water & waste | 2018 |
| A Alexander Tiling Limited | Construction | 2013 |
| A and H Investment (Building) Limited | Construction | 2023 |
| A and H Investment (Hire) Limited | Construction | 2024 |
| A and H Investment (Holdings) Limited | Construction | 2023 |
| A B L Doors & Windows Limited | Wholesale & retail | 2003 |