| D C Power Systems Limited | Manufacturing | 2001 |
| D C Properties (Yorkshire) Ltd | Construction | 2012 |
| D Calpin Joinery & Renovations Limited | Construction | 2023 |
| D Carrington Electrical Services Limited | Construction | 2008 |
| D Frames Limited | Wholesale & retail | 2015 |
| D H Auto Electrics ( York ) Limited | Wholesale & retail | 2011 |
| D H Multiservices Limited | Administrative & support | 2007 |
| D H W Joinery LLP | | 2021 |
| D H Wright Joinery Limited | Manufacturing | 2007 |
| D Inglis Ltd | Professional & scientific | 2010 |
| D J & C Dalton Property Limited | Construction | 2012 |
| D J Cleaning Limited | Water & waste | 2002 |
| D J O'Reilly Consultants Limited | Professional & scientific | 2025 |
| D J Training & Asbestos Consultants Limited | Education | 2016 |
| D Kara Ltd | Other services | 2026 |
| D L P York Limited | Information & communication | 2014 |
| D P Thompson & SON Ltd. | Construction | 2003 |
| D R B S Holdings Limited | Professional & scientific | 2007 |
| D R Shipley Limited | Construction | 2012 |
| D Stephenson Electrical Installations Ltd | Construction | 2011 |
| D Technical Ltd | Professional & scientific | 2019 |
| D Thurlow & SON Ltd | Construction | 2003 |
| D W Brandon Ltd | Financial services | 2022 |
| D Watson Engineering Limited | Manufacturing | 2014 |
| D Williams Healthcare Ltd | Extraterritorial | 2020 |
| D&A Gifts Ltd | Manufacturing | 2024 |
| D&A York Ltd | Hospitality | 2024 |
| D&D Express Logistics Ltd | Transport & logistics | 2016 |
| D&D Windows and Conservatories Limited | Manufacturing | 2025 |
| D&L Carter Ltd | Financial services | 2024 |
| D'Berg Travel Co Limited | Administrative & support | 2021 |
| D'Urton Heights (Preston) Management Company Limited | Households | 2016 |
| D-Tail Plants Ltd | Agriculture & fishing | 2011 |
| D. & M. Atherton Limited | Real estate | 1975 |
| D. Blissett & SON Limited | Construction | 2001 |
| D. C. Farms Limited | Agriculture & fishing | 1995 |
| D. Dunk (Builders) Limited | Construction | 1945 |
| D. F. C. Cleaning Products Limited | | 1982 |
| D. G. Dale & SON Limited | Wholesale & retail | 2003 |
| D. Petty Limited | Construction | 1979 |
| D. R. Johnstone Limited | Construction | 2003 |
| D. Widdicombe Limited | Real estate | 1954 |
| D.A.M.E.N Family Limited | Health & social care | 2022 |
| D.A.P.S.S Limited | Public administration | 2023 |
| D.B.P. Construction Ltd | Construction | 2005 |
| D.F. Yacht Holding Limited | Financial services | 2025 |
| D.H. Properties (Yorkshire) Limited | Real estate | 2003 |
| D.M. Sharp (Northern Hardware Supplies) Limited | Wholesale & retail | 2003 |
| D.N.C. Scaffolding Limited | Construction | 1983 |
| D.R. Dunthorn & SON Limited | Extraterritorial | 1946 |
| D.R.C. Rail Projects Limited | Professional & scientific | 1997 |
| D2CONSULTING Limited | Information & communication | 2010 |
| D4 Transport Ltd | Transport & logistics | 2020 |
| DA & C Ltd | Hospitality | 2022 |
| DA Dentistry Limited | Health & social care | 2026 |
| DAB Fire Engineering Limited | Manufacturing | 2014 |
| DAB Holiday Lettings Ltd | Real estate | 2021 |
| Dabro & Associates Ltd | Professional & scientific | 2013 |
| DAE 1 Limited | Construction | 2025 |
| Daedalus Media Limited | Information & communication | 2014 |
| DAG FM Services Limited | Extraterritorial | 2013 |
| DAH Accountancy Services Limited | Professional & scientific | 2007 |
| Dairy Farm Court (Fulford) Management Company Limited | Real estate | 2024 |
| Daisy Garden Centre Limited | Wholesale & retail | 2011 |
| Daisy Hardcastle Ltd | Wholesale & retail | 2015 |
| Daisy's View (Burbage) Management Company Limited | Households | 2023 |
| Dajs Property Ltd | Real estate | 2019 |
| Dakans Consultancy Ltd | Education | 2015 |
| Dakans Limited | Real estate | 1993 |
| Dalbys Nurseries Limited | Wholesale & retail | 1995 |
| Dale House Property Limited | Real estate | 2025 |
| Dale Rotorcraft Services Ltd | Manufacturing | 2022 |
| Dale View (Yorkshire) Ltd | Real estate | 2018 |
| Dalebrook Ltd | Professional & scientific | 2018 |
| Dales Windows Limited | Manufacturing | 2003 |
| Dalestead Limited | Other services | 1995 |
| Dallol Carbon Limited | Professional & scientific | 2020 |
| Dallol Energy Limited | Manufacturing | 2012 |
| Dallol Forestry Limited | Agriculture & fishing | 2020 |
| Dallol Holdings Limited | Financial services | 2020 |
| Dallol Humber Limited | Manufacturing | 2021 |
| Dallol Operations Limited | Manufacturing | 2012 |
| Dalriada Inns Limited | Hospitality | 2019 |
| Dalworld UK Ltd | Construction | 2019 |
| DAM MAD Media Limited | Professional & scientific | 2020 |
| Damar Farms Limited | Administrative & support | 1996 |
| Damfast Trading Ltd | Health & social care | 2021 |
| Damian Doherty Build Repair Landscape Ltd | Construction | 2022 |
| Damien Mcghie Limited | Information & communication | 2018 |
| Damien Poole Theatre Arts Limited | Arts & recreation | 2016 |
| Damson Yorkshire Ltd | Wholesale & retail | 2026 |
| DAN C Logistics Ltd | Transport & logistics | 2024 |
| DAN Joyce Editorial Ltd | Professional & scientific | 2002 |
| DAN Wright Electrical Ltd | Other services | 2016 |
| DAN Y Bryn Management Company Limited | Households | 2012 |
| Dana Barbers Ltd | Other services | 2025 |
| Danamy Plumbing and Heating Services Limited | Administrative & support | 2006 |
| Dance Space Projects CIC | Arts & recreation | 2023 |
| Dancer Digital Ltd | Information & communication | 2025 |
| Dancing Goat Coffee Limited | Wholesale & retail | 2015 |