| DE Brickwork Limited | Construction | 2026 |
| DE Melo Desserts Ltd | Hospitality | 2018 |
| DE Plant Hire Ltd | Administrative & support | 2022 |
| Deal Realty Ltd | Real estate | 2022 |
| Deal Tyres Ltd | Wholesale & retail | 2025 |
| Deal With IT Solutions Ltd | Information & communication | 2024 |
| Dealdrive Motors Ltd | Wholesale & retail | 2021 |
| Dean Henderson Ceramics Ltd | Construction | 2026 |
| Debargain Group Ltd | Wholesale & retail | 2025 |
| Debnath Limited | Wholesale & retail | 2025 |
| Decanus Insulation Ltd | Construction | 2026 |
| Decent Services Solutions Ltd | Wholesale & retail | 2026 |
| Decision NOW Limited | Wholesale & retail | 2009 |
| Decor Bay Ltd | Wholesale & retail | 2020 |
| Decor Q Ltd | Professional & scientific | 2019 |
| Decorating Direct Limited | Wholesale & retail | 1999 |
| Deeme Ltd | Transport & logistics | 2021 |
| Deep Dive Project Solutions Ltd | Professional & scientific | 2024 |
| Deep's Dream Cakes Ltd | Wholesale & retail | 2025 |
| DEG Construction Ltd | Professional & scientific | 2019 |
| Delhi Lounge Ltd | Hospitality | 2024 |
| Delicious Sandwich Bar Ltd | Hospitality | 2018 |
| Deliver Direct Limited | Transport & logistics | 2023 |
| Dellsteeple Limited | Construction | 1987 |
| Delta Fusion Ltd | Hospitality | 2023 |
| Delta Star North East Limited | Construction | 2024 |
| Demar Transport Ltd | Transport & logistics | 2021 |
| Demeter Agronomy Ltd | Agriculture & fishing | 2024 |
| Denning Group Ltd | Financial services | 2026 |
| Dennis Dixon Limited | Manufacturing | 1987 |
| Dennison Builders Limited | Construction | 2024 |
| Dent Legal Services Limited | Professional & scientific | 2012 |
| Dent Motors Limited | Wholesale & retail | 2009 |
| DEP Technical Services Ltd | Construction | 2025 |
| Department of Caffeine Limited | Hospitality | 2024 |
| Dependent Securities Limited | Health & social care | 2026 |
| Derby Legal Services Ltd | Professional & scientific | 2010 |
| Derek Cooper Consultants Limited | Arts & recreation | 2022 |
| Derek Slack Motors Limited | Wholesale & retail | 1994 |
| Derma Advanced Aesthetics Ltd | Other services | 2025 |
| Dermot Roddy Consulting Ltd | Professional & scientific | 2024 |
| Derry Bars Ltd | Hospitality | 2025 |
| Derwent View Scaffolding Limited | Construction | 2022 |
| Derwent-Alehouse Ltd | Hospitality | 2026 |
| Desert Dunes Ltd | Real estate | 2024 |
| Design Build Space Ltd | Construction | 2021 |
| Design House (North East) Limited | Professional & scientific | 2023 |
| Design, Research & Development Company Limited | Professional & scientific | 1988 |
| Designer Dupes Limited | Wholesale & retail | 2023 |
| Designer Landscapes (Stokesley) Ltd | Administrative & support | 2018 |
| Detail ME Ltd | Wholesale & retail | 2026 |
| Details Matter NE Ltd | Administrative & support | 2024 |
| DEV Convenience Store Ltd | Wholesale & retail | 2024 |
| Development Quarter Ltd | Construction | 2022 |
| DEVICE4U Limited | Wholesale & retail | 2026 |
| Devil Entertainment Ltd | Hospitality | 2025 |
| Devon Associates ( Teesside) Ltd | Real estate | 2025 |
| Devonshire House Dental LAB Limited | Health & social care | 2004 |
| DEX Spray Coatings Ltd | Construction | 2025 |
| Dfvg Ltd | Real estate | 2021 |
| DG Property Investors Ltd | Real estate | 2022 |
| DG Transport & Haulage Ltd | Transport & logistics | 2025 |
| DG10 Sports Management Limited | Professional & scientific | 2021 |
| Dgki Ltd | Hospitality | 2016 |
| DGM Scouting Limited | Arts & recreation | 2018 |
| DGP Solutions Ltd | Manufacturing | 2025 |
| DGS Electrical Limited | Professional & scientific | 2016 |
| DH Gardenworks Ltd | Other services | 2025 |
| DH Grooming Ltd | Wholesale & retail | 2024 |
| DH Rigging Ltd | Manufacturing | 2025 |
| DHA Developments Limited | Construction | 2025 |
| Dhic Ltd | Financial services | 2024 |
| Dhic Partnership LLP | | 2025 |
| DHM Construction and Property Services Ltd | Construction | 2019 |
| DI Wealth Limited | Professional & scientific | 2025 |
| Diablo Seasonings Ltd | Wholesale & retail | 2018 |
| Dial a CAB Taxis Limited | Transport & logistics | 2022 |
| Diamond Cleans C Limited | Administrative & support | 2026 |
| Diamond Fires (Teesside) Ltd | Wholesale & retail | 2024 |
| Diamond Ichina Ltd | Wholesale & retail | 2018 |
| Diamond Roofing & Home Improvements Ltd | Construction | 2025 |
| Diane Daley Limited | Information & communication | 2005 |
| Diane Turner Limited | Education | 2017 |
| DIB Management Services Ltd | Professional & scientific | 2025 |
| Dickinson Property Group Ltd | Real estate | 2021 |
| Different Brains Group Limited | Professional & scientific | 2026 |
| Diffusion Alloys (UK) Limited | Manufacturing | 2012 |
| Diffusion Alloys Holdings Limited | Professional & scientific | 2017 |
| Digital Towns Ltd | Information & communication | 2025 |
| Digitally Secure Limited | Administrative & support | 2016 |
| Digitalopolis Limited | Information & communication | 2019 |
| Digitees Ltd | Professional & scientific | 2021 |
| Dilate Events Limited | Arts & recreation | 2017 |
| Dime Digital Limited | Professional & scientific | 2019 |
| Dimples Group Limited | Education | 2020 |
| Dimples Holding Limited | Financial services | 2024 |
| Dimples Property Limited | Real estate | 2024 |
| Dink Ltd | Information & communication | 2022 |
| Diocese of Middlesbrough Trustee | Professional & scientific | 1997 |
| Direct Care Support (DCS) Limited | Health & social care | 2019 |