| Doner Point One Limited | Hospitality | 2026 |
| Donnie B’S Limited | Wholesale & retail | 2024 |
| Donoghue Tees Valley Engineering Limited | Manufacturing | 2003 |
| Donovan's Lifting Ltd | Transport & logistics | 2026 |
| Donzoko Brewing Company Ltd | Manufacturing | 2016 |
| Doodle Kaboodle Ltd | Manufacturing | 2025 |
| Doom Trans Ltd | Transport & logistics | 2019 |
| Dore Property Group Ltd | Real estate | 2022 |
| Dorman Long United Athletic Club CIC | Education | 2024 |
| Dormor Machine and Engineering Company Limited | Manufacturing | 1979 |
| Dorothy Healthcare Ltd | Administrative & support | 2023 |
| Doru Dobrogeanu Logistcs Limited | Transport & logistics | 2026 |
| DOU6LE6 Ltd | Professional & scientific | 2023 |
| Double Eleven Developing Limited | Information & communication | 2022 |
| Double Eleven Development Limited | Information & communication | 2021 |
| Double Eleven Limited | Information & communication | 2009 |
| Double Flowers Limited | Hospitality | 2019 |
| Dove Group Holdings Ltd | Hospitality | 2026 |
| Downtown Motors NE Limited | Wholesale & retail | 2023 |
| DP & FM Day & SON Ltd | Agriculture & fishing | 2002 |
| Dpearcare Limited | Health & social care | 2025 |
| DPF Clinic Commercial NE Ltd | Wholesale & retail | 2023 |
| DPH Inspection Services Ltd | Professional & scientific | 2014 |
| Dpkit Ltd | Manufacturing | 2025 |
| DPM Events & Catering Ltd | Hospitality | 2025 |
| DPM Tech Ltd | Wholesale & retail | 2020 |
| Dptaylor Engineering Services Ltd | Construction | 2019 |
| DR Gillian Hodgson Consultancy Limited | Health & social care | 2015 |
| Drake Solutions Limited | Information & communication | 2021 |
| Drawflow Ltd | Information & communication | 2026 |
| Drax Trading Ltd | Professional & scientific | 2020 |
| DRE (North East) Ltd | Professional & scientific | 2022 |
| DRE Commissioning Ltd | Professional & scientific | 2024 |
| Dream Apparel Ltd | Wholesale & retail | 2015 |
| Dream Furnishings (NE) Ltd | Wholesale & retail | 2025 |
| Dream Home Lettings Ltd | Real estate | 2024 |
| Dream Home Lettings Management Ltd | Real estate | 2024 |
| Dream Skin Aesthetics Ltd | Other services | 2025 |
| Dreamland Intl Ltd | Education | 2024 |
| Dreams N Themes Events Ltd | Hospitality | 2020 |
| Dreamwork Alloy Refurb Ltd | Wholesale & retail | 2021 |
| Dresser Investment Company Ltd | Real estate | 2021 |
| DRF Electrical Holdings Limited | Financial services | 2023 |
| DRF Electrical Limited | Construction | 2004 |
| DRH Consulting Ltd | Information & communication | 2024 |
| Drink Drive North Limited | Education | 2014 |
| Drip Fairy Ltd | Other services | 2025 |
| Dripfix (UK) Limited | Construction | 2009 |
| Driscoll Property Management Ltd | Real estate | 2025 |
| Drive Away Holiday Limited | Administrative & support | 2021 |
| Drive by Ltd | Wholesale & retail | 2024 |
| Drivesmart Limited | Wholesale & retail | 2007 |
| DRM Planning & Consultancy Ltd | Professional & scientific | 2023 |
| Dromonby Bridge Piggery Ltd | Agriculture & fishing | 2025 |
| Dromonby Developments Ltd | Construction | 2014 |
| Dromonby Farms Ltd | Agriculture & fishing | 2025 |
| Dromonby Grange Developments LLP | | 2011 |
| Drone Hire UK Limited | Professional & scientific | 2025 |
| Drop Away Asian Ltd | Other services | 2015 |
| Dropease Ltd | Wholesale & retail | 2025 |
| Droppoint Courier Services Ltd | Water & waste | 2025 |
| DRS Clinic NCL Ltd | Health & social care | 2026 |
| DRS Skin Clinic Ltd | Health & social care | 2023 |
| Drug & Alcohol Testing Services Limited | Professional & scientific | 2013 |
| Druthi Solutions Ltd | Information & communication | 2022 |
| Drvba Limited | Professional & scientific | 2022 |
| Dryden Property Development Limited | Real estate | 2005 |
| DS Accountancy Services NE Limited | Professional & scientific | 2023 |
| DS Car Sales Ltd | Wholesale & retail | 2019 |
| DS Heights Ltd | Construction | 2025 |
| DS Wills & Estate Planning Ltd | Professional & scientific | 2021 |
| DS777 Solutions Limited | Professional & scientific | 2025 |
| DSB Instrumentation Ltd | Professional & scientific | 2023 |
| DSB Stores Ltd | Real estate | 2017 |
| DSI Trading Ltd | Construction | 2018 |
| DSM Driving School Ltd | Other services | 2017 |
| DSM Inspection Ltd | Professional & scientific | 2024 |
| DSN Tech Ltd | Wholesale & retail | 2025 |
| Dsween Renewables Ltd | Construction | 2025 |
| DT Delrow Limited | Arts & recreation | 2017 |
| DT Windtech Ltd | Construction | 2026 |
| DTK Clothing Ltd | Wholesale & retail | 2025 |
| DTL Valeting and Detailing Ltd | Wholesale & retail | 2019 |
| Dtmurray Ltd | Information & communication | 2025 |
| DUA Noor Ltd | Wholesale & retail | 2024 |
| Dualbound Properties Limited | Construction | 2002 |
| Duane Fibre Services Ltd | Information & communication | 2024 |
| Ducklings and Dolphins Ltd | Arts & recreation | 2018 |
| Ducky Properties Limited | Real estate | 2021 |
| DUE Action Limited | Education | 2015 |
| Duff Properties Ltd | Real estate | 2019 |
| Duffew Consultants Limited | Professional & scientific | 2019 |
| Duffmoney Limited | Wholesale & retail | 2021 |
| Duffy Electrical Limited | Professional & scientific | 2011 |
| Dull NOT to Productions Limited | Information & communication | 2020 |
| Dumitru Hotin Logistics Limited | Transport & logistics | 2025 |
| Duncan Engineering Ltd | Professional & scientific | 2024 |
| Dunelm Properties HF Ltd | Real estate | 2025 |
| Dunnakey Brothers Limited | Wholesale & retail | 1963 |
| DUO Developments NE Ltd | Real estate | 2025 |