| Clarus AI Limited | Information & communication | 2025 |
| Claverhouse Limited | Real estate | 1937 |
| Clay Catering Ltd | Hospitality | 2024 |
| Clean Energy Consultancy Limited | Professional & scientific | 2007 |
| Clean Glow Windows Ltd | Administrative & support | 2024 |
| Clearance DOT TV Ltd | Information & communication | 2018 |
| Clearcompany CIC | Professional & scientific | 2017 |
| Clork Ltd | Manufacturing | 2025 |
| Clowes Nash Auctions Ltd | Wholesale & retail | 2008 |
| Club Culture Ltd | Information & communication | 2025 |
| CLÒ Fold Ltd | Wholesale & retail | 2025 |
| CM Gifts Ltd | Wholesale & retail | 2023 |
| CMK Real Estate Consultancy Ltd | Real estate | 2023 |
| CMP Renovations Limited | Construction | 2021 |
| CNC Management Ltd | Administrative & support | 2012 |
| Co Fresh Enterprise Ltd | Wholesale & retail | 2025 |
| Code Monkey Media Ltd | Information & communication | 2015 |
| Coffee @ Hope Limited | Hospitality | 2015 |
| Cogni R&D Ltd | Information & communication | 2024 |
| Cognigaming Ltd | Information & communication | 2017 |
| Cogniplay UK Ltd | Information & communication | 2024 |
| Cognitive Union Ltd | Education | 2025 |
| Colneis Care Services Ltd | Health & social care | 2009 |
| Coltblue Associates Ltd | Professional & scientific | 2022 |
| Complete Property Cleaning Ltd | Administrative & support | 2025 |
| Complete Property Cleaning Norfolk Ltd | Administrative & support | 2025 |
| Cookhouse Hire Limited | Administrative & support | 2003 |
| COR Trading Ltd | Financial services | 2024 |
| Coral Collective Ltd | Information & communication | 2024 |
| Corenet Computing Ltd | Information & communication | 1999 |
| Cornerstone Norfolk Ltd | Construction | 2026 |
| Cosmetics Doctor Ltd | Health & social care | 2020 |
| Cosmic Dogg Limited | Professional & scientific | 2007 |
| Countryside Secretarial Limited | Professional & scientific | 2010 |
| Cowhams Commercial Holdings Ltd | Real estate | 2026 |
| Cramp Limited | Manufacturing | 2024 |
| Crbjpb Ltd | Construction | 2023 |
| Creek Transport Limited | Transport & logistics | 2008 |
| Cross Keys Public House Limited | Hospitality | 2025 |
| Crown Maintenance Services Limited | Construction | 2024 |
| Crownthorpe Limited | Real estate | 2011 |
| CSH Logistics Ltd | Transport & logistics | 2022 |
| Csmi Limited | Financial services | 2017 |
| CSN Auto's Limited | Wholesale & retail | 2013 |
| CSS Properties Ltd | Real estate | 2022 |
| Culture Mocktail Ltd | Wholesale & retail | 2024 |
| Cup-O-T: Wellness and Therapy Services | Health & social care | 2017 |
| Curtains Curtains Curtains Ltd | Wholesale & retail | 2009 |
| Cutting-Edge UK Limited | Wholesale & retail | 2009 |
| CWL & AHH Holdings Ltd | Real estate | 2023 |
| D J Green Building Services Limited | Construction | 2018 |
| D.G.Caw (Holdings) Ltd | Administrative & support | 2022 |
| D.G.Caw Ltd | Construction | 2017 |
| D5 Holdings Limited | Financial services | 2020 |
| Dairy Farm Cottages Management Co. Limited | Professional & scientific | 1995 |
| Daly Residential Properties Ltd | Real estate | 2024 |
| Darker Designs Ltd | Information & communication | 2012 |
| DCF Roofing Ltd | Construction | 2017 |
| DE Mana Ltd | Wholesale & retail | 2017 |
| Delroi Imperial Limited | Wholesale & retail | 2024 |
| Dennis LEE & Company Limited | Professional & scientific | 2026 |
| Design & Decorate Limited | Construction | 2013 |
| Designaweigh Limited | Wholesale & retail | 2004 |
| Designtec Limited | Information & communication | 2003 |
| Destination Director Ltd | Professional & scientific | 2025 |
| Detailed Touch Ltd | Administrative & support | 2025 |
| Devecchio Limited | Manufacturing | 2025 |
| Dgraves Holdings Ltd | Financial services | 2024 |
| Dharma 8 Ltd | Hospitality | 2017 |
| Dickson Darling Ltd | Construction | 2022 |
| Digital Accounting 4 U Ltd | Professional & scientific | 2022 |
| Digital Blueprint Consulting Limited | Professional & scientific | 2017 |
| Digiworkz Limited | Professional & scientific | 2018 |
| Dikili Ltd | Professional & scientific | 2025 |
| Direct Cloud Backup Limited | Information & communication | 2014 |
| Direct Haul Ltd | Transport & logistics | 2016 |
| Divine Touch Cleaning Services Ltd | Extraterritorial | 2024 |
| DK Norfolk Ltd | Financial services | 2017 |
| Dlec Developments Ltd | Construction | 2022 |
| Dlec Rentals Ltd | Real estate | 2026 |
| DMR Personnel Ltd | Administrative & support | 2023 |
| Dog Soldiers K-9 Walking Services Ltd | Wholesale & retail | 2019 |
| Downham Thirty Limited | Real estate | 2010 |
| DR Natasha's Supplements Ltd | Hospitality | 2026 |
| Drake's Landscapes Ltd | Administrative & support | 2011 |
| Driven Leadership Ltd | Professional & scientific | 2025 |
| Dropworks Customs Ltd | Manufacturing | 2021 |
| Dudley Bros Limited | Extraterritorial | 2017 |
| Dune Properties Limited | Construction | 1973 |
| Dunthorne Landscapes Ltd | Construction | 2022 |
| E & M Home Rental Ltd | Real estate | 2022 |
| E Scott Hairdressing Ltd | Other services | 2026 |
| E.T.S Sales & Hire Limited | Construction | 2003 |
| E.T.S. Studio & Stage Engineering Limited | Administrative & support | 2025 |
| E.V.A. Event Solutions Ltd | Professional & scientific | 2025 |
| Each Group Holdings Limited | Financial services | 2026 |
| EAS (Anglesey) Ltd | Professional & scientific | 2013 |
| East 10 Enterprises Limited | Real estate | 2020 |
| East 10 Limited | Financial services | 2020 |
| East 10 Power Limited | Energy | 2021 |