| D Bobar Ltd | Health & social care | 2016 |
| D C - Side Media Limited | Professional & scientific | 2009 |
| D C Joinery Services Ltd | Construction | 2003 |
| D Greer Ltd | Information & communication | 2010 |
| D K Electricals (N E) Limited | Construction | 2003 |
| D Lisiewska Ltd | Health & social care | 2013 |
| D M C Training Services Limited | Information & communication | 2004 |
| D Mchale Landscaping Groundworks & Building Limited | Construction | 2007 |
| D Miller Building Services Ltd | Construction | 2026 |
| D N S Insurance Services Limited | Financial services | 1999 |
| D P O'Dwyer Bloodstock Limited | Agriculture & fishing | 2022 |
| D R Groundworks & Construction Ltd | Construction | 2020 |
| D Sinkiewicz Ltd | Health & social care | 2014 |
| D Sutherland Distribution Services Ltd | Transport & logistics | 2021 |
| D&A AVL Ltd | Health & social care | 2019 |
| D&A Property Services (NE) Limited | Construction | 2025 |
| D&B Transport Ltd | Transport & logistics | 2015 |
| D&G Private Ltd | Wholesale & retail | 2023 |
| D&M Brickwork & Repointing Ltd | Construction | 2025 |
| D'Modish Fingerfoods and Bakes Ltd | Wholesale & retail | 2025 |
| D-U Leisure Ltd | Hospitality | 2019 |
| D. G. Bricklayers Limited | Construction | 2017 |
| D. White Electricals Limited | Construction | 2009 |
| D.J.R Investments (NE) Limited | Real estate | 2017 |
| D.J.R. Consultancy Services Limited | Real estate | 2019 |
| D.K.P. Window Services Limited | Construction | 1997 |
| D.P. Fasteners Limited | Wholesale & retail | 1986 |
| D28FX Ltd | Financial services | 2023 |
| Daas Ubina Ltd | Real estate | 2022 |
| Dacio Caballero Stunts Ltd | Arts & recreation | 2015 |
| Dacobs Ltd | Construction | 2025 |
| Dacon Fabrications Limited | Manufacturing | 1989 |
| DAD Offshore Ltd | Construction | 2022 |
| Dadko Ltd | Real estate | 2024 |
| DAF Developments Limited | Construction | 2021 |
| Dage Ltd | Wholesale & retail | 2015 |
| Dagul T W Ltd | Professional & scientific | 2022 |
| Daily Daisy Limited | Wholesale & retail | 2025 |
| Daily Pour Ltd | Wholesale & retail | 2024 |
| Daisymill Investments Limited | Real estate | 2025 |
| Dali (Newcastle) Ltd | Wholesale & retail | 2016 |
| Dalkowska Ltd | Health & social care | 2020 |
| Dalmore FS Ltd | Professional & scientific | 2018 |
| Dalston House Ltd | Hospitality | 2022 |
| Dalston Leisure Swimming Pool Ltd | Arts & recreation | 2023 |
| Dalton Holdings Limited | Financial services | 2018 |
| Dalton Offshore Safety Limited | Administrative & support | 2016 |
| DAN Smith Studios Limited | Arts & recreation | 2016 |
| DAN Stohr Ltd | Manufacturing | 2025 |
| Dana's Family Bakery Limited | Manufacturing | 2018 |
| Daneo Ltd | Other services | 2011 |
| Daniel Auto Centre Limited | Extraterritorial | 2025 |
| Daniel Craig Residential Limited | Real estate | 2014 |
| Daniel Dobson Limited | Manufacturing | 2023 |
| Daniel's Property Company Limited | Real estate | 2024 |
| Danken Bashefer Ltd | Real estate | 2026 |
| Danny Mcatominey Ltd | Information & communication | 2015 |
| Dans Tans Limited | Other services | 2018 |
| Dansky's (Gateshead) Limited | Wholesale & retail | 2011 |
| Dansky's Mini Market Ltd | Wholesale & retail | 2021 |
| Daredevils & Clowns Limited | Wholesale & retail | 2014 |
| Dark Citi Limited | Professional & scientific | 2020 |
| Dark Parx Limited | Professional & scientific | 2020 |
| Darksky UK IDA C.I.C. | Professional & scientific | 2021 |
| Darman Psychotherapy Limited | Health & social care | 2025 |
| Darren ORD Electrical Services Limited | Construction | 2025 |
| Dashpoint Limited | Information & communication | 2025 |
| Dashy Enterprises Ltd | Wholesale & retail | 2018 |
| Data Processing Supplies Limited | Wholesale & retail | 1979 |
| Daughmech Engineering Limited | Professional & scientific | 2025 |
| Dave Hall T/A UK Textiles Ltd | Wholesale & retail | 2025 |
| Davey Macrail Limited | Manufacturing | 2017 |
| David & Myriam Investments Ltd | Real estate | 2022 |
| David & Myriam Investments One Ltd | Real estate | 2026 |
| David Clark Golf Ltd | Arts & recreation | 2013 |
| David Ward Trading Ltd | Wholesale & retail | 2015 |
| Davidson Motor Group Ltd | Wholesale & retail | 2025 |
| Davincci's Ltd | Hospitality | 2020 |
| Davisher Ltd | Real estate | 2023 |
| Davison Construction Northern Ltd. | Construction | 2019 |
| Davison Energy Ltd | Professional & scientific | 2025 |
| Davison Solutions Limited | Construction | 2011 |
| Dawson Accounting Ltd | Professional & scientific | 2022 |
| Dawson Playscapes Limited | Construction | 2008 |
| Dawson Three Limited | Administrative & support | 2011 |
| Day 2 Day Holdings Limited | Wholesale & retail | 2026 |
| Dayta Designs Limited | Wholesale & retail | 1985 |
| Dayta Ltd | Financial services | 2021 |
| Dbdc Properties Limited | Real estate | 2023 |
| DBS Holdings Limited | Professional & scientific | 2006 |
| DBS Properties (NE) Ltd | Real estate | 2011 |
| Dbsna Ltd | Other services | 2020 |
| DBW Wealth Management Ltd | Financial services | 2022 |
| DC Wilde Ltd | Wholesale & retail | 2026 |
| Dc's Dream Clean Limited | Administrative & support | 2025 |
| Dcare Team Limited | Hospitality | 2023 |
| DCG Family Investco Limited | Financial services | 2024 |
| DCG Hold Limited | Financial services | 2024 |
| DCL Investments Ltd | Real estate | 2018 |
| DCM (North East) Ltd | Construction | 2021 |