| Cloverleaf Pizza (Harold Park) Limited | Hospitality | 2016 |
| Cloverleaf Pizza (Lakeside) Limited | Hospitality | 2016 |
| Cloverleaf Pizza (Ockendon) Limited | Hospitality | 2016 |
| Cloverleaf Solutions Limited | Hospitality | 2014 |
| CM Freight Services Limited | Transport & logistics | 2008 |
| Cmediation Ltd | Professional & scientific | 2022 |
| CNC Interiors Limited | Construction | 2007 |
| Coach House (EOT) Consultancy Ltd | Professional & scientific | 2023 |
| Coach House (EOT) Limited | Professional & scientific | 2022 |
| Coach House Consultancy (EOT) Ltd | Professional & scientific | 2022 |
| Coaching Dynamics Limited | Professional & scientific | 2017 |
| Colemans Farm Limited | Hospitality | 2020 |
| Coleyplex Investments Limited | Real estate | 2025 |
| Coleyplex Limited | Professional & scientific | 2026 |
| Commonwealth Caravans Limited | Wholesale & retail | 2011 |
| Composite Decking World Ltd | Construction | 2024 |
| Concordant Trade Limited | Wholesale & retail | 2024 |
| Concourse Display and Media Ltd | Professional & scientific | 2024 |
| Coopersale Pre-School Ltd | Education | 2026 |
| Coraxe Cleaning Services Ltd | Water & waste | 2023 |
| Core Four Developments Limited | Construction | 2025 |
| Cotswolds Prestige Limited | Transport & logistics | 2026 |
| Cottonwood Construction Limited | Construction | 2020 |
| Couta Managment Limited | Professional & scientific | 2025 |
| Cranwell Consultancy Limited | Professional & scientific | 2013 |
| Crown Business Estates Limited | Real estate | 2015 |
| Crown Holdings Limited | Professional & scientific | 2000 |
| Crown House 2023 RTM Company Limited | Households | 2023 |
| Crown Services Management LLP | | 2011 |
| Crown Underlays & Accessories Ltd | Wholesale & retail | 2023 |
| Crown Worldwide Hospitality Ltd | Hospitality | 2021 |
| Crownfield Holdings Limited | Professional & scientific | 1951 |
| CRV Interiors Limited | Construction | 2020 |
| Crypto Key Collection Holdings Limited | Wholesale & retail | 2022 |
| Crystal Clear Car Sales Ltd | Wholesale & retail | 2026 |
| CS Shepherd Property Development Limited | Real estate | 2024 |
| CS Shepherd Property Holdings Limited | Real estate | 2024 |
| CS Shepherd Property Letting Limited | Real estate | 2024 |
| Cstar Properties Management Ltd | Real estate | 2024 |
| CTI Concerts Ltd | Arts & recreation | 2024 |
| Cured Phones Ltd | Other services | 2024 |
| Custom Steel Fabrication (Essex) Ltd | Construction | 2018 |
| CW Electrical Ltd | Construction | 2026 |
| CW Managed Services Limited | Administrative & support | 2014 |
| Cyclecare Kensington Limited | Manufacturing | 2019 |
| CYI Consulting Limited | Professional & scientific | 2026 |
| D & N Humm Limited | Construction | 2012 |
| D K & SON Building Contractors Limited | Construction | 2003 |
| D.C.Pickering Constructions Ltd | Construction | 2024 |
| D3N9 UK LLP | | 2024 |
| DAD "N" BOY Electricals Ltd | Construction | 2019 |
| Dale Design Engineering Ltd | Extraterritorial | 2014 |
| Dale Wood Capital Limited | Financial services | 2013 |
| Daniel James Electrical Limited | Construction | 2011 |
| Darlington Court Management Limited | Households | 2026 |
| Darnicle Hill Nursery Ltd | Agriculture & fishing | 2012 |
| David Alexander Removals & Storage Limited | Transport & logistics | 2009 |
| Daystone Fireplaces (Surrounds) Limited | Manufacturing | 1989 |
| DB Surveying Services Limited | Professional & scientific | 2025 |
| Debonaire Property Solutions Ltd | Real estate | 2018 |
| Decanter Lounge Limited | Hospitality | 2026 |
| Decorative Floors Ltd | Wholesale & retail | 2024 |
| Delmac Limited | Administrative & support | 2001 |
| Delta Cable Jointing Limited | Construction | 2019 |
| Designers Network | Professional & scientific | 2005 |
| Develli Trading Ltd | Construction | 2025 |
| Devin Anscomb Limited | Administrative & support | 2002 |
| Dezobuk Ltd | Information & communication | 2010 |
| Diet LAB by Priya Ltd | Manufacturing | 2025 |
| Dimitar Kyuchukov Ltd | Construction | 2014 |
| Dinamica Ltd | Real estate | 2025 |
| Dineout Ltd | Hospitality | 2024 |
| Doe's Services Limited | Administrative & support | 1984 |
| DOO DAA Creative Kitchen CIC | Health & social care | 2026 |
| Doublelix Limited | Manufacturing | 2005 |
| DOW Stunts Limited | Arts & recreation | 2014 |
| Dowd & Sons Limited | Construction | 2019 |
| Draper Talent Ltd | Administrative & support | 2024 |
| Driftway Properties Limited | Real estate | 2017 |
| Drizzle Wayne Enterprises Limited | Arts & recreation | 2020 |
| DS Chequers Inn Ltd | Hospitality | 2025 |
| Dsquare Developments Limited | Construction | 2020 |
| DTC Holdings Ltd | Administrative & support | 2016 |
| Dualglaze Limited | Wholesale & retail | 2009 |
| Dunedin 197 Ltd | Professional & scientific | 2017 |
| DW Audio and Visual Limited | Administrative & support | 2024 |
| Dwelling Properties Limited | Extraterritorial | 2015 |
| Dylan Tombides 38 Limited | Other services | 2014 |
| E.H.Thompson & SON (London) Limited | Manufacturing | 1944 |
| E.V.S Vehicle Services Ltd | Wholesale & retail | 2025 |
| East London Car & Commercial Limited | Wholesale & retail | 2002 |
| Easypath Limited | Households | 1986 |
| Easywork Group Ltd | Construction | 2019 |
| Eawconsulting Ltd | Information & communication | 2024 |
| ECG Limited | Administrative & support | 2018 |
| Eclipse Pest Control Limited | Administrative & support | 2004 |
| Eco Air Conditioning Services Ltd | Energy | 2022 |
| Ecothread Solutions Ltd | Manufacturing | 2025 |
| Edicos London Limited | Other services | 2022 |
| Edison Energy Limited | Construction | 2022 |