| Dalerose Limited | Real estate | 1985 |
| Dalyan Deniz Ltd | Hospitality | 2025 |
| Daniel James Hospitality Ltd | Hospitality | 2023 |
| Danielle Unway Ltd | Professional & scientific | 2015 |
| DAP Surveys Limited | Construction | 2022 |
| Dark Cobalt Ltd | Information & communication | 2022 |
| Darkel Limited | Professional & scientific | 2010 |
| Darlington Partners Limited | Professional & scientific | 2025 |
| Darlington Property Consulting Limited | Administrative & support | 2024 |
| Dart PR Limited | Professional & scientific | 2009 |
| Data Homes Ltd | Construction | 2026 |
| Dave COX Construction Limited | Construction | 2021 |
| Davey Enterprise Ltd | Wholesale & retail | 2023 |
| David Ball Agencies Ltd | Real estate | 2012 |
| David Moss Ltd | Financial services | 2025 |
| David Taylor Design Limited | Professional & scientific | 2014 |
| Deakins Court (Redruth) Management Company Ltd | Real estate | 2008 |
| Del-Marine Limited | Transport & logistics | 1992 |
| Deliveries Dunn Ltd | Transport & logistics | 2024 |
| Denning Construction Management Limited | Construction | 2017 |
| Depth Recovery Ltd | Wholesale & retail | 2026 |
| Derek Gannon Limited | Administrative & support | 2018 |
| Design Build Maintain Limited | Construction | 2010 |
| Deskhop Co-Working Ltd | Real estate | 2020 |
| Deva House Residential LLP | | 2024 |
| DFP Limited | Construction | 2024 |
| DFT149 Ltd | Hospitality | 2024 |
| DG Property Investment Ltd | Real estate | 2015 |
| Dhama Sun Ltd | Health & social care | 2024 |
| DHG Consultancy Limited | Construction | 2013 |
| DHG Residential Investments Limited | Construction | 2025 |
| DHG Station Road Limited | Construction | 2026 |
| DHT Solar Limited | Professional & scientific | 2023 |
| Diamond Abodes Limited | Hospitality | 2019 |
| Diamond Consultancy Services Ltd | Professional & scientific | 2022 |
| Dicky BAG Limited | Wholesale & retail | 2008 |
| Dight Holdings Ltd | Households | 2021 |
| Digital Natives Agency Ltd | Professional & scientific | 2023 |
| Dinneen Limited | Real estate | 2016 |
| Dips FS Ltd | Professional & scientific | 2026 |
| Direct ABA Limited | Education | 2025 |
| Discover Earth Limited | Information & communication | 2022 |
| Dish Cornwall Limited | Hospitality | 2019 |
| Dive Newquay Limited | Wholesale & retail | 2011 |
| Diverse Learners Ltd. | Education | 2015 |
| Divine Lines Limited | Arts & recreation | 2025 |
| DJ Civils & Surveys Limited | Professional & scientific | 2013 |
| DMS Rail Limited | Construction | 2007 |
| DO Bathrooms Limited | Wholesale & retail | 2022 |
| DO IT Digitally Ltd | Professional & scientific | 2019 |
| DOH RAY & ME Ltd | Education | 2026 |
| Domestiq Limited | Information & communication | 2026 |
| Doodles and Pops Nursery Limited | Education | 2021 |
| Douglas Property Management Limited | Real estate | 2019 |
| Dowdell Mining Limited | Mining & quarrying | 2013 |
| DP Gutierrez Ltd | Health & social care | 2017 |
| DPM Plastering Ltd | Construction | 2026 |
| DPM Recovery and Transport Services Ltd | Transport & logistics | 2025 |
| DR Justine Smith Ltd | Health & social care | 2023 |
| Draconic Distribution Ltd | Wholesale & retail | 2025 |
| Dragonfly Botanicals Ltd | Wholesale & retail | 2024 |
| Dragonstone Treasures Ltd | Manufacturing | 2019 |
| Droneprep Ltd | Information & communication | 2019 |
| Drowsy Dragon Games Ltd | Manufacturing | 2025 |
| DRW Couriers Ltd | Transport & logistics | 2015 |
| DSO Air Conditioning Refrigeration Limited | Manufacturing | 2024 |
| Duchy Enterprises Limited | Financial services | 2013 |
| Duck Soup (UK) Limited | Administrative & support | 2011 |
| Dudden Construction Limited | Construction | 2010 |
| Dunn IT Newquay Ltd | Construction | 2026 |
| Dwell Cornwall Ltd | Construction | 2020 |
| DWM Properties (Midlands) Limited | Real estate | 2006 |
| Dysujo Ltd | Financial services | 2025 |
| E - Moat Trades Limited | Wholesale & retail | 2020 |
| Earth Play Ltd | Wholesale & retail | 2021 |
| East and West Creative Group Ltd | Professional & scientific | 2021 |
| Easy Mediation Network Ltd | Information & communication | 2025 |
| Easy Online Group Ltd | Wholesale & retail | 2023 |
| Ebbtide Management Company Limited | Real estate | 2021 |
| Eco Escapes Ltd | Hospitality | 2022 |
| Eco Finishes Limited | Construction | 2023 |
| Eco Garden Buildings Limited | Construction | 2015 |
| Eco Insulation Cornwall Limited | Construction | 2025 |
| Eden Adventures (UK) Limited | Arts & recreation | 2011 |
| Eden Lettings Limited | Real estate | 2025 |
| Edge Escapes Ltd | Hospitality | 2025 |
| EDGE57 Ltd | Wholesale & retail | 2025 |
| Edsport Ltd | Manufacturing | 2026 |
| Edukus Money Limited | Information & communication | 2021 |
| Edvested JB Ltd | Information & communication | 2026 |
| Edward Bears Private Daycare Limited | Health & social care | 2023 |
| Eight Global Limited | Administrative & support | 2022 |
| Ekspres Cars Limited | Transport & logistics | 2019 |
| EL Camino Bracelets Ltd | Manufacturing | 2015 |
| EL Huichol Ltd | Wholesale & retail | 2020 |
| EL Rollo Surf Designs Ltd | Professional & scientific | 2020 |
| Elanacre Limited | Extraterritorial | 1997 |
| Elderfield Electrical Limited | Construction | 2012 |
| Electrical Services (Cornwall) Limited | Construction | 1945 |
| Electrical Services (Holdings) Limited | Financial services | 2013 |