| Csaba Vaszily Transport Ltd | Transport & logistics | 2011 |
| Cubo Apartments (Farringdon) Limited | Real estate | 2022 |
| Cubo Apartments Limited | Real estate | 2020 |
| Cucina Italiano Limited | Hospitality | 2025 |
| Cyprus by Design Limited | Administrative & support | 1994 |
| D & C (Bucknalls) Ltd | Construction | 2024 |
| D & C (Cherry) Ltd | Construction | 2025 |
| D & C (Cranbrook) Ltd | Construction | 2025 |
| D & C (Hornsey) Ltd | Construction | 2025 |
| D & C (Locutorium) Ltd | Construction | 2024 |
| D & C (Park Street) Ltd | Construction | 2024 |
| D & C (Wheathampstead) Ltd | Construction | 2025 |
| D and J Services Limited | Professional & scientific | 2006 |
| D M Jones Trading Ltd | Transport & logistics | 2020 |
| D&B Building Limited | Construction | 2018 |
| D&R Estate Services Ltd | Agriculture & fishing | 2024 |
| D. J. Harfield Plant Hire Limited | Construction | 2004 |
| D.B. Builders Construction Limited | Wholesale & retail | 2001 |
| D.L.S.E Ltd | Real estate | 2020 |
| D6 Productions Limited | Arts & recreation | 2021 |
| DA Vinci's Workshop Ltd | Education | 2017 |
| Dali Property Ltd | Real estate | 2020 |
| DAN Meakin Consultancy Ltd | Professional & scientific | 2024 |
| Danecroft Stables Ltd | Agriculture & fishing | 2019 |
| Danesbury Care Limited | Arts & recreation | 1993 |
| Danesbury Park Limited | Hospitality | 2016 |
| Danesbury Park Management (Mansion) Limited | Real estate | 1998 |
| Danesbury Park Management (Mews) Limited | Households | 1998 |
| Daniel Desmond Ayot Limited | Real estate | 1999 |
| Danisha Properties Ltd | Real estate | 2019 |
| Daylight CIS UK Limited | Professional & scientific | 2003 |
| Dbdm Interim Solutions Ltd | Professional & scientific | 2021 |
| DDW Property Investments Ltd | Real estate | 2026 |
| Dean Austin Promotions Limited | Arts & recreation | 2012 |
| Decimate Limited | Information & communication | 2010 |
| Deea Consulting Limited | Wholesale & retail | 2018 |
| Demmr Ltd | Real estate | 2024 |
| Devailytics Limited | Extraterritorial | 2025 |
| DHW Consulting Ltd | Professional & scientific | 2016 |
| Diamond Birch Limited | Arts & recreation | 2015 |
| Digital Retail Advisory Ltd | Professional & scientific | 2019 |
| Digswell Home and Gardens Limited | Administrative & support | 2019 |
| Digswell Nurseries Limited | Mining & quarrying | 2020 |
| Direct Services/Coating/Vehicles Ltd | Wholesale & retail | 2001 |
| District and Circle (Welclose) Limited | Real estate | 2022 |
| District and Circle Limited | Real estate | 2004 |
| DJ COX Building Services Ltd | Construction | 2019 |
| DK Creative Ltd | Professional & scientific | 2019 |
| DKT (Enterprises) Limited | Wholesale & retail | 1975 |
| Doe-Eyed Ltd | Wholesale & retail | 2024 |
| Domisouth Limited | Real estate | 2015 |
| Doris Edwards Limited | Administrative & support | 2002 |
| Dotty Things Ltd | Wholesale & retail | 2024 |
| DPM Admin Services Ltd | Administrative & support | 2013 |
| DR Bhavika Kotecha Limited | Health & social care | 2022 |
| DR Tamara Whiston Ltd | Administrative & support | 2020 |
| DRL Agent Pro Limited | Information & communication | 2026 |
| Drummond Security Ltd | Manufacturing | 2024 |
| E-Resolve Limited | Information & communication | 2013 |
| Earthpoints Limited | Manufacturing | 2008 |
| Eatiology Limited | Hospitality | 2018 |
| Ecognito Ltd | Professional & scientific | 2023 |
| Economia Limited | Information & communication | 2013 |
| Eden Mechanical & Electrical Ltd | Construction | 2023 |
| Edumatters Limited | Professional & scientific | 2007 |
| Efficient One Limited | Wholesale & retail | 2024 |
| Eight Music Limited | Arts & recreation | 2018 |
| Elan Graphics Ltd | Manufacturing | 2014 |
| ELEGANCE4U Beauty Ltd | Other services | 2019 |
| Elevate and Create Limited | Education | 2023 |
| Elevate Bespoke Carpentry Ltd | Manufacturing | 2025 |
| Elite Kitchen Developments Limited | Construction | 2022 |
| Elysium Group Limited | Real estate | 2022 |
| Emani Gardens Ltd | Administrative & support | 2025 |
| Emion Holdings Limited | Other services | 2016 |
| Empowers Holdings Limited | Real estate | 2017 |
| Enclosure Zoolutions Ltd | Construction | 2026 |
| Enerlytica Ltd | Information & communication | 2025 |
| Entire Cargo Logistic Ltd. | Transport & logistics | 2013 |
| Entire Finance Ltd | Financial services | 2009 |
| Ethica Consultancy Limited | Information & communication | 2013 |
| Eurofina Limited | Professional & scientific | 1997 |
| Eyes on the Cloud Limited | Information & communication | 2018 |
| Fairchild Motor Company Limited | Wholesale & retail | 2011 |
| Famm DG Limited | Real estate | 2017 |
| FAN Steward Authority Limited | Information & communication | 2025 |
| Farmanagement Limited | Hospitality | 2018 |
| Fauztrading Ltd | Wholesale & retail | 2018 |
| Fern Hill Services Limited | Professional & scientific | 2023 |
| Fin-Biz Ltd | Professional & scientific | 2017 |
| Finishing Touch Detailing Ltd | Wholesale & retail | 2023 |
| Fish Tank Investments Limited | Real estate | 2017 |
| Fitme Pilates Ltd | Arts & recreation | 2024 |
| Flacks Limited | Wholesale & retail | 2014 |
| Flag Consulting Limited | Professional & scientific | 2025 |
| Flarehill Computers Limited | Information & communication | 1987 |
| Flawless Flooring Solutions Limited | Construction | 2013 |
| Flofix Plumbing & Heating Ltd | Construction | 2019 |
| Flowright Construction Limited | Construction | 2021 |
| Forty Knots Investments Limited | Real estate | 2018 |