| Dominic Reyes Magic Limited | Fareham | 2006 |
| Dominic Toms Golf Ltd | Esher | 2015 |
| Dominic Watson Ltd | Margate | 2019 |
| Dominic Welch Limited | Chudleigh | 2018 |
| Dominion Events Limited | London | 2012 |
| Dominion Fitness Limited | Liverpool | 2025 |
| Dominion Gaming Ltd | Ayr | 2021 |
| Dominion of Drama Ltd | Hove | 2020 |
| Dominionaire Academies CIC | Luton | 2025 |
| Dominique Levy Limited | London | 2014 |
| Dominique Moore Arts Limited | Liverpool | 2016 |
| Dominique Thornton Racing Limited | Doncaster | 2023 |
| Dominitemporal Services Limited | Newark | 1987 |
| Domino Presentations Ltd | Westcliff-On-Sea | 2013 |
| Domino Productions Ltd | Bishop'S Stortford | 2024 |
| Dominographics Limited | Ilford | 2014 |
| Dominus Fitness Limited | York | 2015 |
| Dommcart Ltd | Oakham | 2025 |
| Domoney Limited | Stratford Upon Avon | 2003 |
| Domoney Productions Limited | Stratford-Upon-Avon | 2024 |
| Domus Media Ltd | London | 2025 |
| DON Black Music Limited | 3 Dorset Rise | 1978 |
| DON Brown Ltd | Harleston | 2013 |
| DON Cricket Ltd | Chelmsford | 2014 |
| DON Davis Boxing Academy CIC | London | 2021 |
| DON DON Entertainment Ltd | London | 2020 |
| DON Graham Fitness Limited | Llandrindod Wells | 2023 |
| DON Graham Fitness Studios Limited | Llandrindod Wells | 2026 |
| DON Money Trees Ltd | London | 2026 |
| DON Padel Limited | Wakefield | 2025 |
| DON Quixote Limited | London | 2017 |
| DON Salvador Ltd | Colchester | 2025 |
| DON Singh Promotions Limited | Rochester | 2016 |
| DON Speake (London) Limited | London | 2024 |
| Don'T BE a Square Ltd | London | 2024 |
| Don'T Blame ME Ltd | Cambridge | 2024 |
| Don'T Break 345 Limited | Chelmsford | 2009 |
| Don'T Ever Ring the Bell Limited | Matlock | 2016 |
| Don'T Flop Entertainment Ltd | Liverpool | 2022 |
| Don'T Forget Limited | Richmond | 2024 |
| Don'T Forget to Live Ltd | London | 2021 |
| Don'T GET Locked in Ltd | London | 2018 |
| Don'T Just Records Ltd | Peacehaven | 2022 |
| Don'T POP ME NOW Limited | Great Waldingfield | 2021 |
| Don'T Rain Ltd | Ventnor | 2015 |
| Don'T Stop the Beat Productions Ltd | London | 2017 |
| Donaghadee Heritage Preservation Company | Donaghadee | 2016 |
| Donal Moran Coaching Ltd | London | 2024 |
| Donald Brown Enterprise Limited | Wolverhampton | 2019 |
| Donald From Skye Ltd | Cardiff | 2018 |
| Donald SZE Limited | Northampton | 2023 |
| Donate WIN Limited | London | 2025 |
| Donatts Ltd | London | 2022 |
| Donavan Hepburn Limited | Birmingham | 2023 |
| Doncaster & District Model Engineering Society Limited | Doncaster | 2000 |
| Doncaster and District Youth Football League Limited | Doncaster | 2021 |
| Doncaster Athletic Club | Doncaster | 2006 |
| Doncaster Belles CIC | Doncaster | 2025 |
| Doncaster City Football Club Ltd | Doncaster | 2022 |
| Doncaster Culture and Leisure Trust | Doncaster | 2002 |
| Doncaster Dartes S.C | Sheffield | 2009 |
| Doncaster Golf Driving Range Limited | Doncaster | 2007 |
| Doncaster Golf Range Ltd | Doncaster | 2013 |
| Doncaster Gymnastics Academy Ltd | Doncaster | 2010 |
| Doncaster Indoor Bowling Club Ltd | Doncaster | 1998 |
| Doncaster Jazz Alumni Ltd | Rotherham | 2023 |
| Doncaster Little Theatre Limited | Doncaster | 2007 |
| Doncaster Moto Parc Limited | Retford | 2013 |
| Doncaster Music Festival Ltd | Doncaster | 2021 |
| Doncaster Performance Venue Limited | Doncaster | 2012 |
| Doncaster Racing Limited | York | 2014 |
| Doncaster Rovers Belles Ladies Football Club Limited | Doncaster | 2009 |
| Doncaster Rovers Limited | Doncaster | 1999 |
| Doncaster Rovers Training Centre Holiday Camps Ltd | Doncaster | 2025 |
| Doncaster Rugby League Club Limited | Doncaster | 2010 |
| Doncaster Rugby League Football Club (1986) Limited | Leeds | 1986 |
| Doncaster Skate Cooperative Ltd | Doncaster | 2023 |
| Doncaster Town Field Sports Club Limited | Doncaster | 2022 |
| Doncaster Training Centre Limited | Doncaster | 2020 |
| Done Brothers (Cash Betting) Limited | Warrington | 1976 |
| Done for Ltd | Stroud | 2011 |
| Done Right Events Ltd | Bradford | 2021 |
| Done That Ltd | Winchester | 2021 |
| Done That NOW What Ltd | London | 2025 |
| Donek Limited | Hornchurch | 2016 |
| Doni Bobes Ltd | London | 2016 |
| Donisthorpe Community Interest Company | Swadlincote | 2021 |
| Donjuan&Co Ltd | London | 2025 |
| Donkey and GEE Ltd | Barry | 2022 |
| Donkey World International Limited | London | 1995 |
| Donkin Enterprises Limited | Queensway, Petts Wood | 1981 |
| Donkin Music Limited | London | 2025 |
| Donmar Productions Limited | London | 2008 |
| Donmar Warehouse Projects Limited | London | 1982 |
| Donna Benjamin Photography Limited | London | 2003 |
| Donna Douglas Ltd | Rainhill | 2014 |
| Donna Grant Limited | London | 2012 |
| Donna Patricia Turner Limited | Trethomas Caerphilly | 2024 |
| Donna Salado Design Limited | Northampton | 2024 |
| Donna YT Productions Ltd | London | 2020 |