| Duplify Ltd | Bristol | 2024 |
| Duplo Ltd | Addlestone | 1985 |
| Duplo UK Limited | Addlestone | 1988 |
| Dupont Alpine Breaks Ltd | Urmston | 2021 |
| Duport Domains Ltd | Bristol | 2010 |
| Duport Ltd | Bristol | 2005 |
| Duport Online Limited | Bristol | 2005 |
| Dura UK Limited | Bristol | 1998 |
| Durable Collection Ltd | London | 2015 |
| Durable Vision Limited | Henley-On-Thames | 1989 |
| Duracore Limited | Stourbridge | 2019 |
| Duraframe Systems Limited | West Midlands | 1985 |
| Duramark Limited | Suffolk | 1992 |
| Duran Searle Ltd | London | 2017 |
| Durant Developments Limited | Bristol | 2011 |
| Duranta Consulting Ltd | Keighley | 2018 |
| Durbar Trading Limited | Leominster | 1995 |
| Durdygozel Davies Ltd | Maidenhead | 2024 |
| Durell Properties Limited | Erith | 2013 |
| Duressguard Limited | Bury St. Edmunds | 2021 |
| Durham Accident Repair Centre Limited | Hartlepool | 2024 |
| Durham Benevolence Limited | Tyne & Wear | 1956 |
| Durham Businesswear Limited | Newcastle Upon Tyne | 2018 |
| Durham Chemicals Limited | Park Cowley Road | 1918 |
| Durham City Coaches Limited | Durham | 2025 |
| Durham Cooling Ltd | Gateshead | 2025 |
| Durham County Cricket Club | Chester Le Street | 1991 |
| Durham County Cricket Club Developments Limited | Chester Le Street | 2015 |
| Durham Estates UK Limited | Kent | 2005 |
| Durham Inns Limited | Newcastle Upon Tyne | 2004 |
| Durham Mark Festival 2029 Limited | Pegswood | 2022 |
| Durham Minibuses Ltd | Durham | 2020 |
| Durham Travel Services Limited | Carlisle | 2011 |
| Durham Vale Developments Limited | Newcastle Upon Tyne | 2005 |
| Duri Products Ltd | Oldham | 2017 |
| Durlene Mauricia Kharchenko Limited | Kington | 2024 |
| Duronic Foundation Limited | Essex | 2016 |
| Duronic Limited | Romford | 2013 |
| Durowipers Ltd | Stonehouse | 2010 |
| Durrant & Company Ltd | Chester | 2025 |
| Durston House School Limited | London | 1965 |
| Duru Sailboat Ltd | London | 2025 |
| Dury Service Limited | St. Leonards-On-Sea | 2020 |
| DUS CU Vantul Ltd | London | 2022 |
| Dusenbery Europe Limited | Ipswich | 2013 |
| Duskside Limited | London | 1986 |
| Dustco International Limited | Hereford | 2019 |
| Dustquip Limited | Taunton | 2024 |
| Dusty Digital Co., Ltd | Beckenham | 2021 |
| Dusty Rose Ltd | London | 2025 |
| Dustyhall Ltd | Salford | 2014 |
| Dusun Durian Plantations Limited | London | 1905 |
| Dutch & Dutch (Residential) Limited | London | 2006 |
| Dutch Crunch Ltd | Carmarthen | 2016 |
| Dutch Hydro Limited | Manchester | 2021 |
| Dutch Stock House Limited | Harrogate | 2013 |
| Dutchie Bicycles Ltd | London | 2008 |
| Duthie Legal Services Ltd | Harpenden | 2013 |
| Dutton & Hallmark (Funeral Services) Ltd | Nottingham | 2003 |
| Duty to Create Ltd | Llandudno | 2014 |
| Dutytrade | London | 1987 |
| Duval Bygg Invest Limited | London | 2020 |
| Duval Bygg Limited | London | 2020 |
| Duvest Limited | London | 2011 |
| Duvs Limited | Greenford | 2024 |
| Duzenli Yachting Ltd | London | 2026 |
| Duzmo Motorcycles Limited | London | 2017 |
| DV Brewery Ltd | Doncaster | 2013 |
| DV4 Properties Castlepoint NO.2 UK Limited | London | 2001 |
| DVF Recruitment Limited | London | 2014 |
| DVG Limited | Bristol | 2010 |
| Dvmindustrial Ltd | Borehamwood | 2015 |
| DVP Management Limited | Ednaston, Ashbourne | 2019 |
| DVS Group Co., Ltd. | West Midlands | 2023 |
| DVS Healthcare Ltd | Oldham | 2008 |
| DVS Manticore Ltd | Cranleigh | 2025 |
| DVW Project Management Solutions Ltd. | Gloucester | 2012 |
| DVX Limited | London | 2014 |
| DW Financial Services Ltd | Oldham | 2015 |
| DW Property Services (NI) Limited | Ballyrobert | 2012 |
| DW Technical Solutions Ltd | Eastleigh | 2022 |
| Dwaggel Ltd | Boston | 2019 |
| Dwayne Simpson Foundation CIC | London | 2015 |
| Dwell on Sea Limited | Sutton | 2017 |
| Dwelling Properties Limited | Ongar | 2015 |
| Dwellvesting Limited | Sutton | 2016 |
| DWS Building Contractors Limited | Maldon | 2017 |
| DWS Consulting Ltd | Stafford | 2019 |
| DWW Group Co., Ltd. | Beckenham | 2018 |
| DX Communications Limited | Glasgow | 1991 |
| DX Specialist Cars Ltd | Wolverhampton | 2024 |
| Dxarma Limited | Blackpool | 2025 |
| Dxcover SUB Limited | Glasgow | 2021 |
| DXG Group Limited | Leamington Spa | 2024 |
| DXN Associates Limited | Gosport | 2006 |
| DXU Holding Ltd | London | 2024 |
| Dyako International Co., Ltd | London | 2024 |
| DYB Logistics Limited | Derby | 2024 |
| Dyck Company Limited | London | 2020 |
| Dyenamic Solutions Ltd | Cheltenham | 2023 |