| Cttart Ltd | Real estate | 2025 |
| Cub's DEN Ltd | Wholesale & retail | 2001 |
| Cube Legal Limited | Professional & scientific | 2010 |
| Cube Scaffolding Ltd | Construction | 2026 |
| Cubeser Limited | Real estate | 2020 |
| Cucina Restaurants Limited | Hospitality | 2005 |
| Culcha Ltd | Information & communication | 2024 |
| Cultissima Station Ltd | Wholesale & retail | 2022 |
| CUP of Jojo Ltd | Arts & recreation | 2019 |
| CUP of Learning Ltd | Professional & scientific | 2016 |
| Cupid Holdings Limited | Financial services | 2023 |
| Cupid Offline Limited | Wholesale & retail | 2024 |
| Cupid Trade Limited | Wholesale & retail | 2024 |
| Cura People CIC | Health & social care | 2026 |
| Curlys Motorcycles Ltd | Wholesale & retail | 2021 |
| Curry Leaves Groceries Ltd | Wholesale & retail | 2024 |
| Curve on Curve Limited | Wholesale & retail | 2022 |
| Custard Communications Ltd | Administrative & support | 2007 |
| Custom Golf Works Limited | Wholesale & retail | 2025 |
| Cutting-Hedge.Com Limited | Administrative & support | 2004 |
| CV Navigator Ltd | Administrative & support | 2024 |
| CVM Holdco Ltd | Financial services | 2023 |
| CVN Investments Ltd | Financial services | 2026 |
| CWR Ventures Limited | Administrative & support | 2014 |
| Cyber in the Box Limited | Information & communication | 2020 |
| Cyber Innova Ltd | Information & communication | 2022 |
| Cyber Secure Limited | Information & communication | 2013 |
| Cybersafe Academy Ltd | Information & communication | 2026 |
| Cycle Confident Limited | Education | 2009 |
| Cyintsy Limited | Information & communication | 2015 |
| Cylan Properties Limited | Real estate | 2003 |
| CYP (UK) Limited | Administrative & support | 2001 |
| CYP Europe Limited | Administrative & support | 2008 |
| CYS Prop Co Limited | Real estate | 2019 |
| D & H Automotive Engineers Ltd | Wholesale & retail | 2011 |
| D a Whiteley Limited | Wholesale & retail | 1996 |
| D B Props Ltd | Information & communication | 2002 |
| D Green & Co (Cooker & Heating Solutions) Ltd | Construction | 2025 |
| D J Connolly Brickwork Limited | Construction | 2024 |
| D J M Dental Laboratory Ltd | Manufacturing | 2012 |
| D S Flooring Ltd | Administrative & support | 2009 |
| D&D Porter Limited | Health & social care | 2012 |
| D&D Reeve Brickwork Ltd | Construction | 2022 |
| D&J Roofing and Building Ltd | Construction | 2022 |
| D-Jays Integrated Services Ltd | Health & social care | 2025 |
| D.A.E Property Management Ltd | Real estate | 2024 |
| D.W.H.Investments(Woking)Limited | Real estate | 1964 |
| D9PROPERTY Limited | Real estate | 2016 |
| Dacjat Properties Ltd | Real estate | 2026 |
| Dack Design & Photography Limited | Professional & scientific | 2019 |
| Dacosta Developments LLP | | 2022 |
| Dacre Property Management Limited | Households | 2017 |
| Dada Muma Ltd | Wholesale & retail | 2022 |
| Dadakhet Properties Ltd | Construction | 2026 |
| Daddy Cat Records Limited | Information & communication | 2022 |
| Dafd Ltd | Public administration | 2020 |
| Daffodil Investors Ltd | Real estate | 2025 |
| Daily Save Limited | Wholesale & retail | 2013 |
| Daintree Gardens Limited | Administrative & support | 2009 |
| Dalelodge Limited | Professional & scientific | 1987 |
| Damarel Systems International Limited | Information & communication | 1988 |
| Damini AI Holdings Ltd | Financial services | 2025 |
| Dana Kinesthetic Therapies Ltd | Professional & scientific | 2020 |
| Danbe Limited | Health & social care | 2013 |
| Dandy Designs Ltd | Other services | 2011 |
| Dandy Snacks Ltd | Hospitality | 2020 |
| Danhodev Ltd | Information & communication | 2015 |
| Daniel Thorpe Electrical Limited | Construction | 2023 |
| Daniel Thorpe Estates Limited | Real estate | 2023 |
| Daniel Thorpe Holdings Limited | Financial services | 2025 |
| Daniel.H.Rails Ltd | Construction | 2016 |
| Daniels Associates Ltd | Professional & scientific | 2024 |
| Danlotte Machen Ltd | Wholesale & retail | 2008 |
| Danos Consulting Limited | Real estate | 2022 |
| Danos Properties Limited | Real estate | 2025 |
| Dansos Properties Ltd | Real estate | 2024 |
| DAR AL Anwar CIC | Education | 2024 |
| Darby Holmes Interiors Limited | Construction | 2025 |
| Darcy Action Ltd | Arts & recreation | 2026 |
| Dariston Land & Development Limited | Other services | 2003 |
| Dark Matter Systems Limited | Information & communication | 1994 |
| Dark Property Ltd | Professional & scientific | 2006 |
| Dark Spark Consulting Ltd | Professional & scientific | 2023 |
| Dark Valley Ltd | Financial services | 2025 |
| Darland Limited | Information & communication | 1989 |
| Darling Consulting Ltd | Professional & scientific | 2026 |
| Darqz Ltd | Wholesale & retail | 2022 |
| Darr House M.I. Limited | Agriculture & fishing | 2022 |
| Dartmouth Properties Limited | Households | 2007 |
| Daryl Goodrich Films Limited | Information & communication | 2018 |
| Daryl Goodrich Limited | Information & communication | 2005 |
| DAS Property Services (UK) Ltd | Real estate | 2018 |
| Dashell Fonai Technology (UK) Ltd | Wholesale & retail | 2025 |
| Data Driven Performance Ltd | Information & communication | 2026 |
| Data Mesh Solutions Limited | Information & communication | 2022 |
| Data Motor Ltd | Information & communication | 2023 |
| Data Tech Media Limited | Professional & scientific | 2018 |
| Dataforcare Ltd | Professional & scientific | 2025 |
| Dave Emery Limited | Information & communication | 2007 |
| Davenpark Ltd | Information & communication | 2018 |