| Dickson MBI Company Limited | Edgware | 2018 |
| Didactease Limited | London | 2008 |
| Didcot Railway Centre Limited | Didcot | 1990 |
| Diddi Dance (Franchising) Limited | London | 2005 |
| Diddi Dance (South East London) Ltd | London | 2009 |
| Diddi Malek and Associates Limited | Andover | 1999 |
| Diddikicks Warrington Ltd | Leeds | 2015 |
| Didsbury Beer Festival CIC | Manchester | 2019 |
| Didsbury Cricket Ground Company Limited | Manchester | 1923 |
| Didsbury F.C. Limited | Cheadle | 2003 |
| Didsbury Golf Club (Trading) Limited | Northenden | 2021 |
| Didsbury Golf Club Limited | Manchester | 1945 |
| Didsbury Parsonage Trust | Manchester | 2011 |
| Didsbury Playing Fields Association | Cheadle | 2011 |
| Didsbury Runners Limited | Manchester | 2019 |
| Didsbury Sports Ground Limited | Cheadle | 1981 |
| Didsbury TOC H Rugby Football Club Limited | Manchester | 2011 |
| Diego Barros Limited | Poole | 2021 |
| Diego Holland Limited | London | 2016 |
| Diesel Gym CIC | London | 2019 |
| Diesel House Studios Limited | Weston-Super-Mare | 2004 |
| Dieting Intelligently & Exercising Together Limited | Aylesbury | 2020 |
| Difa Arts Ltd | London | 2024 |
| Different Creature Ltd | Glasgow | 2020 |
| Different Drummer Productions Limited | London | 1987 |
| Different Orbit Promotions Ltd | Saddleworth | 2026 |
| Different Voice Limited | Anstruther | 1995 |
| Different Works Theatre Productions | Edinburgh | 2018 |
| Differentcreations Ltd | London | 2024 |
| Differprint Limited | London | 2014 |
| Difficult Stage Ltd | Cardiff | 2014 |
| Diffract Ltd | Nottingham | 2023 |
| Diffusion Productions Limited | Farnborough | 2021 |
| Diffusion Theatrical Limited | Farnborough | 2026 |
| Différance C.I.C. | London | 2025 |
| Difr Ltd. | Sheffield | 2015 |
| DIG Deep Coaching Ltd | Belfast | 2011 |
| DIG IT Agility Shows Ltd | Ruthin | 2015 |
| DIG Media Limited | Salford | 2015 |
| Digbeth Jazz Limited | Birmingham | 2024 |
| Digby Diverse SFX Limited | Bucks | 2008 |
| Diggers & Enthusiasts CIC | Lewes | 2025 |
| Diggi Books Limited | 3 Dorset Rise | 2016 |
| Diggle Blues Festival Limited | Oldham | 2010 |
| Digi GEM Limited | Manchester | 2024 |
| Digibox Arts Ltd | Bristol | 2023 |
| Digidraws Ltd | London | 2025 |
| Digigrowth Ltd | London | 2025 |
| Digijuke 1 Ltd | Fraserburgh | 2013 |
| Digimental Studio Ltd | London | 2012 |
| Digiset Limited | London | 2018 |
| Digit Music Limited | Walsall | 2018 |
| Digital Art Boutique Limited | London | 2021 |
| Digital Art Fair UK Limited | Cardiff | 2022 |
| Digital Arts Studios | Belfast | 2008 |
| Digital Asset Emporium Limited | Benfleet | 2019 |
| Digital Block Limited | London | 2007 |
| Digital Character Games Ltd | Okehampton | 2014 |
| Digital Concert Media Ltd | London | 2025 |
| Digital Dream City Ltd | London | 2009 |
| Digital Farm Ltd | London | 2013 |
| Digital Gateway 24 Limited | Folkestone | 2014 |
| Digital Graphics Limited | Chelmsford | 2015 |
| Digital Hardcore Recordings Ltd | London | 2014 |
| Digital History Creations Limited | London | 2018 |
| Digital Leaf Ltd | Wolverhampton | 2022 |
| Digital Light Limited | London | 2005 |
| Digital Marketing Dynamics Ltd | Newport | 2023 |
| Digital Media Content Limited | Walton-On-Thames | 2021 |
| Digital Mind AI Ltd | London | 2026 |
| Digital Mysteries Ltd. | Royston | 1997 |
| Digital Network Distributions Invest Ltd | Dover | 2021 |
| Digital Orchid Graphics Limited | Sheffield | 2013 |
| Digital Prime Music Ltd | Cardiff | 2025 |
| Digital Quest Limited | Chichester | 2002 |
| Digital Reflection Studios Ltd | Dunstable | 2020 |
| Digital Resource Vault Ltd | Skelton, Saltburn-By-The-Sea | 2026 |
| Digital Rewards Group Limited | Altrincham | 2014 |
| Digital Sport 12 Ltd | Newbury | 2023 |
| Digital Stuffs Ltd | London | 2025 |
| Digital Teddy Touring Limited | London | 2018 |
| Digital Vellum Ltd | Kingswinford | 2022 |
| Digital Women's Archive North C.I.C. | Rochdale | 2016 |
| Digitop Ltd | Alton | 1998 |
| Digitraxx Limited | London | 2013 |
| Digmusik Ltd | Shrewsbury | 2025 |
| Dignitas Esports UK Ltd. | London | 2016 |
| Digswell Arts Trust | Digswell Welwyn | 2012 |
| Digswell Lake Society | Welwyn Garden City | 1987 |
| DIGWYDDIADAU8EVENTS Limited | Pwllheli | 2017 |
| Diig Fit Ltd | London | 2022 |
| Dijon Studios CIC | Stockport | 2026 |
| Dilate Events Limited | Middlesbrough | 2017 |
| Dildar Taekwondo Limited | London | 2024 |
| Dilemma Sounds Ltd | Cardiff | 2025 |
| Dileva Fitness Limited | Harrow | 2018 |
| Dilf Productions Limited | Glasgow | 2022 |
| Diligent Cogency Ltd | London | 2015 |
| Diligent Collective Ltd | Manchester | 2024 |
| Diligent Health Limited | Pudsey | 2017 |