| Cooper and Cooper Property (Dorset) Ltd | Construction | 2018 |
| Cooper Briggs Clarke Ltd. | Hospitality | 2017 |
| Copper Studio Limited | Arts & recreation | 2019 |
| Copperplane Limited | Real estate | 1996 |
| Corbridge Fittings Limited | Manufacturing | 2024 |
| Corbsoft Limited | Professional & scientific | 2015 |
| Cornelia the Professional Organiser Ltd | Transport & logistics | 2021 |
| Cornick Accountancy Ltd | Professional & scientific | 2025 |
| Corton Denham Consulting Ltd. | Public administration | 2011 |
| Cosmic Sway Method Ltd | Other services | 2022 |
| Cottage Lodge Hotel Limited | Hospitality | 2019 |
| Cove Holidays Limited | Real estate | 2024 |
| Cove Property Limited | Real estate | 2017 |
| Covebrook Homes and Holidays Ltd | Real estate | 2016 |
| Covebrook Services Limited | Administrative & support | 2015 |
| CPN Architects Ltd | Professional & scientific | 2012 |
| Cpras Group Limited | Financial services | 2020 |
| Crabb Consultants Limited | Administrative & support | 1993 |
| Crafter Explorer Technology Ltd | Manufacturing | 2021 |
| Crafty Ltd | Manufacturing | 2017 |
| Craig Pinder Limited | Administrative & support | 2010 |
| Creare Hair & Beauty Design Limited | Other services | 2021 |
| Crescent Leisure (GB) Limited | Real estate | 1992 |
| Crescent Street Let’S Limited | Hospitality | 2023 |
| Crest Swim School Limited | Education | 2019 |
| Crewfit Ltd | Arts & recreation | 2024 |
| Cronus Electronics Ltd | Professional & scientific | 2017 |
| Cross Shore Design Ltd | Professional & scientific | 2013 |
| Cross Shore Holdings Limited | Professional & scientific | 2018 |
| Crossworks Design Ltd | Professional & scientific | 2017 |
| Crowman LLP | | 2007 |
| Crustacean Limited | Real estate | 2021 |
| Crustacean Station Ltd | Hospitality | 2025 |
| CSK Holdings Limited | Construction | 2016 |
| CSL Event Tech Ltd | Professional & scientific | 2023 |
| Csoffshore Limited | Professional & scientific | 2016 |
| CSR Marine Limited | Manufacturing | 2013 |
| CTM Home Improvements Ltd | Construction | 2023 |
| CUE Media Solutions Ltd. | Information & communication | 2005 |
| Culinary OIL Developments Limited | Hospitality | 1999 |
| Cumbria House Freehold Management Ltd | Real estate | 2024 |
| Cumbria House Workington Leasehold 57 Ltd | Real estate | 2024 |
| Curtis Fields Management Limited | Real estate | 2015 |
| Curtis Technology (UK) Limited | Information & communication | 1998 |
| Custom FD Services Limited | Professional & scientific | 2018 |
| Custom House Cafe Weymouth Limited | Hospitality | 2018 |
| CV Solutions (South) Ltd | Professional & scientific | 2024 |
| D & M Groundworks (Dorset) Limited | Construction | 2018 |
| D & S London Limited | Wholesale & retail | 2023 |
| D and B Mechanical Limited | Construction | 2012 |
| D and E Taxis (Dorset) Limited | Transport & logistics | 2021 |
| D and M (Holdings) Limited | Professional & scientific | 1988 |
| D Barnes Consultancy Limited | Manufacturing | 2023 |
| D G Plastics Limited | Manufacturing | 2003 |
| D J Contracts (Doors) LLP | | 2010 |
| D J Groundworkers Limited | Construction | 1999 |
| D P Decorating Dorset Ltd | Construction | 2023 |
| D R Sams Limited | Construction | 2010 |
| D S C Southwest Limited | Wholesale & retail | 2020 |
| D W Display Ltd | Administrative & support | 2006 |
| D W Roofing Dorset Limited | Construction | 2013 |
| D Whyton Building Services Limited | Construction | 2010 |
| D&T Angell Hospitality Ltd | Hospitality | 2025 |
| D'Arcy Aesthetics Ltd | Health & social care | 2021 |
| D'Arcy Performance Coaching Ltd | Administrative & support | 2023 |
| D.B. Jones Limited | Real estate | 1981 |
| D.S.M Electrical Contractors Limited | Construction | 2014 |
| D.T. Moore (Sales) Ltd | Wholesale & retail | 2001 |
| D4 Events Limited | Information & communication | 2011 |
| Dade’S Design Studio Ltd | Wholesale & retail | 2025 |
| Dagnastar Limited | Real estate | 2001 |
| DAINC23 Limited | Administrative & support | 2023 |
| Dambusters Fitness Ltd | Arts & recreation | 2025 |
| Damsole Technologies Limited | Information & communication | 2022 |
| DAN Dalton Broadcast Ltd | Information & communication | 2011 |
| DAN Stuttle Marine (Weymouth) Limited | Wholesale & retail | 2018 |
| Dane Servicing & Repairs Ltd | Wholesale & retail | 2022 |
| Dangina Limited | Construction | 2017 |
| Daniels Fish & Chips Limited | Hospitality | 2002 |
| Danmor Lodge Ltd | Administrative & support | 2001 |
| Danny Spink & SON Limited | Transport & logistics | 2006 |
| Dapple Limited | Information & communication | 2019 |
| Dario's Kebab Limited | Hospitality | 2025 |
| Darren Poole Builders Limited | Construction | 2012 |
| Darwin Care Ltd | Administrative & support | 2002 |
| Darwin Holdings Limited | Construction | 2017 |
| Dave Bevis Haulage Limited | Transport & logistics | 2003 |
| Dave Rogers Building Ltd | Construction | 2025 |
| David Braithwaite Services Limited | Construction | 2002 |
| David Cake Limited | Financial services | 2002 |
| David Foot (Windsbatch) Limited | Administrative & support | 2010 |
| David Foot Limited | Agriculture & fishing | 1960 |
| David Jones Property Limited | Construction | 1992 |
| David Lawrence P3M Ltd | Public administration | 2020 |
| David M Jones (Commercial Maintenance) Limited | Administrative & support | 2000 |
| David Short Consulting Limited | Professional & scientific | 2015 |
| Davidmac Consulting Ltd | Professional & scientific | 2022 |
| Dawn Adams Procurement Consultancy Limited | Professional & scientific | 2026 |
| Daylesford (Weymouth) Management Company Limited | Households | 2020 |
| Daylight and Sunlight Solutions Ltd | Professional & scientific | 2020 |