| Corrennie Press Limited | Information & communication | 2021 |
| Cosic Carpenters Limited | Construction | 2002 |
| Cosmos Landscapes Limited | Administrative & support | 2017 |
| Couchmore Property Garage Co. Limited | Real estate | 1980 |
| Court Support Limited | Administrative & support | 2008 |
| Cousins Studio Ltd | Professional & scientific | 2020 |
| Coworth Partners Ltd | Wholesale & retail | 2024 |
| COX & Readman Developments Limited | Real estate | 1968 |
| Cozzy Housing Ltd | Real estate | 2017 |
| Cquester Ltd | Professional & scientific | 2023 |
| Craam Ltd | Real estate | 2022 |
| Craft & Crumb Limited | Wholesale & retail | 2019 |
| Cranmer Court Management Company Limited | Extraterritorial | 2001 |
| Cranston Construction Ltd | Construction | 2024 |
| Creative Costumes Limited | Manufacturing | 2022 |
| Creative Terriers Ltd | Administrative & support | 2020 |
| Creststone Construction Ltd | Construction | 2024 |
| Crimsonvale Limited | Real estate | 2007 |
| Criserna Limited | Extraterritorial | 2025 |
| Cross Lane Care Ltd | Health & social care | 2013 |
| Crosshex Properties Limited | Real estate | 2022 |
| Crossways Cafe Bar Limited | Hospitality | 2026 |
| Crystal Complex London Ltd | Wholesale & retail | 2024 |
| Cube Coaching Limited | Arts & recreation | 2022 |
| CUE Jump Ltd | Information & communication | 2026 |
| Cuenca Properties Limited | Real estate | 2019 |
| Cuffley Banks Ltd | Real estate | 2008 |
| Curate Studio Ltd | Wholesale & retail | 2025 |
| Curious Jellyfish Ltd | Professional & scientific | 2020 |
| Curtis & Shaw Ltd | Professional & scientific | 2015 |
| Custom Golf Global Limited | Wholesale & retail | 2022 |
| Custom Investments Limited | Extraterritorial | 2023 |
| CVW Property Holdings Ltd | Real estate | 2017 |
| Cyrus Beauty Ltd | Other services | 2021 |
| D&C 3318 Property Ltd | Extraterritorial | 2019 |
| D'Oro Property Ltd | Real estate | 2024 |
| D'S Property Dreams Ltd | Extraterritorial | 2019 |
| D.L. Marine Services Ltd | Other services | 2002 |
| Dalgar Investments Limited | Real estate | 1959 |
| Dalgar Limited | Real estate | 1959 |
| Daly Equity Connections Limited | Professional & scientific | 2017 |
| Danator Ltd | Manufacturing | 2023 |
| Danex Chauffeurs London Ltd | Transport & logistics | 2025 |
| Dapjf Holdings Ltd | Financial services | 2023 |
| Darm Group Limited | Real estate | 2020 |
| Darm Homes Limited | Real estate | 2020 |
| Darm Investments Limited | Real estate | 2019 |
| Dartsbible Limited | Professional & scientific | 2020 |
| Data for Purpose Limited | Professional & scientific | 2022 |
| Dataspring Technologies Ltd | Information & communication | 2019 |
| Dath & Bergh Property Ltd | Real estate | 2018 |
| David Kolb Consultancy Ltd | Information & communication | 2020 |
| Dawes Property Management Limited | Real estate | 1999 |
| Daylight Discos Limited | Arts & recreation | 2024 |
| Daytime Discos Limited | Arts & recreation | 2024 |
| Db's Affordable Living Ltd | Construction | 2019 |
| DDK Property Management Ltd | Real estate | 2023 |
| Decim LLP | | 2023 |
| Deco&Time Ltd | Construction | 2024 |
| DECOR8LONDON Limited | Construction | 2011 |
| Decorstandard Corp UK Ltd | Wholesale & retail | 2018 |
| Deepclean & Property Services Ltd | Construction | 2026 |
| Defacto Associates Limited | Professional & scientific | 2010 |
| Defined PR Ltd | Professional & scientific | 2026 |
| Dentaku Ltd | Mining & quarrying | 2022 |
| Denton Road Residents Association Limited | Households | 1987 |
| Depth 2 Surface Limited | Professional & scientific | 2023 |
| Derbydale Limited | Extraterritorial | 2004 |
| Derek Medford Properties Ltd | Real estate | 2018 |
| Desaur Healthcare Ltd | Construction | 2011 |
| Design Sight Architects Ltd | Professional & scientific | 2025 |
| Design Silver Fish UK Ltd | Information & communication | 2018 |
| Detail Management Services Limited | Other services | 1995 |
| Dexworks Limited | Professional & scientific | 2011 |
| Diamond Management Limited | Administrative & support | 1988 |
| Digital Drama CIC | Information & communication | 2018 |
| Digital Drama Productions Limited | Information & communication | 2013 |
| Digital Waste Tracking Ltd | Information & communication | 2025 |
| Dilapidated Phones Limited | Wholesale & retail | 2026 |
| Diligence Logistic Solutions Ltd | Administrative & support | 2018 |
| Diligence Security Solutions Ltd | Administrative & support | 2008 |
| Dinate Engineering Ltd | Construction | 2017 |
| Dinate Property Ltd | Financial services | 2025 |
| Dinate Relocation Ltd | Hospitality | 2025 |
| Diogenes Ltd. | Construction | 1998 |
| Direct Group Roofing Ltd | Construction | 2020 |
| Discover Attic Ltd | Wholesale & retail | 2015 |
| Distributed Solutions Worldwide Ltd | Information & communication | 2020 |
| Divsalar Enterprise Ltd | Real estate | 2023 |
| Divsalar Estates Ltd | Real estate | 2019 |
| Divsalar Ltd | Information & communication | 2017 |
| DIX Properties Ltd | Real estate | 2017 |
| DJP UK Investments Ltd | Real estate | 2017 |
| DLJ Hospitality Catering Ltd | Hospitality | 2018 |
| Dlov Limited | Real estate | 2018 |
| Dmeo Properties Ltd | Real estate | 2019 |
| DNB 33 Limited | Real estate | 2019 |
| Dog Agility Coaching Ltd | Other services | 2024 |
| Doglistener Ltd | Other services | 2019 |
| Dogs by Paula Ltd | Education | 2025 |