| Daypark Ltd | Education | 1996 |
| DAZ Eleganz Limited | Hospitality | 2025 |
| DB Creative Ltd | Arts & recreation | 2022 |
| DB Glazing Ltd | Construction | 2025 |
| DB Offshore Inspection Services Ltd | Professional & scientific | 2014 |
| DB Professional Gutter Cleaning Ltd | Administrative & support | 2026 |
| DB Projects Limited | Construction | 2015 |
| DB Sparky Limited | Construction | 2024 |
| DB80 Properties Ltd | Real estate | 2023 |
| DBF Law Limited | Professional & scientific | 2015 |
| Dblify Ltd | Information & communication | 2026 |
| Dbluvd Concepts Ltd | Information & communication | 2025 |
| DC HUN Limited | Hospitality | 2025 |
| DC Kitchens & Joinery Limited | Construction | 2018 |
| DC Locum Services Limited | Wholesale & retail | 2023 |
| DC Prestige Pipefitting Ltd | Construction | 2024 |
| DC Realisations 2023 Limited | Wholesale & retail | 2013 |
| DC5 Investments Ltd | Real estate | 2020 |
| DC81 Ltd | Wholesale & retail | 2025 |
| Dcoi Properties Ltd | Real estate | 2025 |
| DCR Media Ltd | Information & communication | 2020 |
| Dcraig Properties Ltd | Real estate | 2021 |
| DCS Cleaning Network Limited | Administrative & support | 2000 |
| Dcsc Properties Limited | Real estate | 2023 |
| DCT Northumbria Ltd | Real estate | 2026 |
| DCW Structural Engineering Ltd | Professional & scientific | 2022 |
| DD Financial Limited | Professional & scientific | 2018 |
| DD Holdings Limited | Financial services | 2023 |
| DD Investments Ltd | Extraterritorial | 2013 |
| DD Newcastle Limited | Hospitality | 2023 |
| Dd&K Retails UK Limited | Wholesale & retail | 2025 |
| DDG Property Development Ltd | Real estate | 2024 |
| Ddlc Property Limited | Real estate | 2026 |
| Ddmusic Ltd | Information & communication | 2023 |
| Ddog Media Ltd | Professional & scientific | 2025 |
| DE Beauvoir House Limited | Wholesale & retail | 2025 |
| DE Great Educational Consult Ltd | Education | 2025 |
| DE Kiingz Entertainment CIC | Hospitality | 2020 |
| DE Kim's Properties Ltd | Real estate | 2024 |
| DE LA FET Healthcare Ltd | Health & social care | 2023 |
| DE Mowbray Holdings Limited | Real estate | 2021 |
| DE Roofing and Property Services Ltd | Construction | 2025 |
| DE Silva Foundation | Health & social care | 2021 |
| DE Winter + Cartner Ltd | Professional & scientific | 2025 |
| De-Deluxe Ventures Ltd | Hospitality | 2023 |
| Deacon House Management Company Limited | Professional & scientific | 2004 |
| Deadgood Holdings Limited | Professional & scientific | 2008 |
| Deadgood Trading Limited | Manufacturing | 2008 |
| Deadwood Studio Limited | Wholesale & retail | 2016 |
| Deaf Communications Limited | Other services | 2017 |
| Deaflink North East | Health & social care | 2012 |
| Deal Kuest Ltd | Wholesale & retail | 2026 |
| Deal Refrigeration & Air Conditioning Ltd | Manufacturing | 2019 |
| Dealer Direct Ltd | Wholesale & retail | 2024 |
| Dealnza Ltd | Wholesale & retail | 2026 |
| Dealtop Limited | Transport & logistics | 1986 |
| Dean & Co Estates Limited | Real estate | 2023 |
| Dean Court Hotel Ltd | Extraterritorial | 2014 |
| Dean Express Newcastle Ltd | Wholesale & retail | 2026 |
| Dean Gillespie Financial Advice Ltd | Professional & scientific | 2019 |
| Dean Liddle Enterprises Limited | Professional & scientific | 2007 |
| Dean Venture Limited | Hospitality | 2004 |
| Deanleigh Properties Ltd | Real estate | 2026 |
| Dear Dotty Ltd | Wholesale & retail | 2025 |
| Deascorp Ltd | Information & communication | 2023 |
| Debd Limited | Hospitality | 2023 |
| Debit Finance Collections PLC | Financial services | 1997 |
| Debonair Beauty Ltd | Other services | 2025 |
| Deboneyre Limited | Hospitality | 2019 |
| Deborah C Anderson Ltd | Professional & scientific | 2023 |
| Debra Santangelo Ltd | Information & communication | 2004 |
| Debt Settle Financial Ltd | Information & communication | 2020 |
| Debut Studio Limited | Administrative & support | 2019 |
| Decade Media Agency Ltd | Professional & scientific | 2019 |
| Decadence Hair Specialists Ltd | Other services | 2022 |
| Decadeon Holdings Limited | Professional & scientific | 2015 |
| Decanter House Ltd | Wholesale & retail | 2025 |
| Decarco Limited | Manufacturing | 2023 |
| Decked Stickers Ltd | Wholesale & retail | 2025 |
| Declan Ventures (UK) Ltd | Financial services | 2019 |
| Deco Furnitures Ltd | Wholesale & retail | 2021 |
| Decom Vessel Limited | Transport & logistics | 2021 |
| Decoras Furniture Limited | Manufacturing | 2010 |
| Decorative Plaster Company (Newcastle) Limited | Extraterritorial | 1927 |
| Deea's Delicatessen Ltd | Wholesale & retail | 2020 |
| Deehan Property Limited | Real estate | 2012 |
| Deen Legal Services Ltd | Professional & scientific | 2025 |
| Deep Clean Car Ltd | Administrative & support | 2025 |
| Deep North Group Ltd | Wholesale & retail | 2022 |
| Deep Space Media Limited | Information & communication | 2023 |
| Deep Strain Buildings Limited | Construction | 2025 |
| Deepclean & Solar Care Solution Ltd | Administrative & support | 2026 |
| Deepcleanne Ltd | Information & communication | 2026 |
| Deepsee AI Limited | Professional & scientific | 2017 |
| Deeptread Limited | Education | 2026 |
| Deepwater Energy Services Ltd | Professional & scientific | 2025 |
| Dee’S Wellness Centre Ltd | Other services | 2025 |
| Defender Security Consultants Ltd | Administrative & support | 2025 |
| Definition IP Limited | Professional & scientific | 2015 |
| Definitive Marketing Limited | Professional & scientific | 2009 |