| DB Paint Sprayers Limited | Construction | 2024 |
| DB Property Lets Ltd | Real estate | 2025 |
| DBC Logistics & Haulage Ltd | Transport & logistics | 2015 |
| DBC Plumbing & Heating (Southern) Ltd | Construction | 2017 |
| DBE Contracting Ltd | Construction | 2020 |
| DBK Homes Ltd | Real estate | 2021 |
| DBM Residential Ltd | Real estate | 2022 |
| DBN Capital Ltd | Real estate | 2024 |
| DBN Food Enterprise Ltd | Hospitality | 2025 |
| DBN Foods Ltd | Hospitality | 2025 |
| DBN Group Ltd | Professional & scientific | 2022 |
| DBN Property Management Ltd | Households | 2025 |
| Dbrightest Ltd | Extraterritorial | 2023 |
| DBS Financial Services Ltd | Financial services | 2015 |
| DBV Concept Ltd | Construction | 2023 |
| DC & Sons Transport and Logistics Ltd | Transport & logistics | 2019 |
| DC Beams Limited | Construction | 2017 |
| DC Builders (Southern) Ltd | Construction | 2007 |
| DC Cycles Southampton Ltd | Wholesale & retail | 2025 |
| DC Employment Solicitors Limited | Professional & scientific | 2011 |
| DC IMI Ltd | Wholesale & retail | 2020 |
| DC Pictures Limited | Information & communication | 2023 |
| DCA Transport Logistics Limited | Transport & logistics | 2019 |
| Dcfo Property Limited | Real estate | 2022 |
| DCI Global Solutions Ltd | Mining & quarrying | 2021 |
| DCM Flooring Limited | Construction | 2018 |
| DCP Academy Ltd | Other services | 2023 |
| DCP Haulage Ltd | Transport & logistics | 2014 |
| Dcrux Solutions Ltd | Information & communication | 2023 |
| DD Info Logistics Limited | Transport & logistics | 2025 |
| DD Obsession Limited | Other services | 2025 |
| DD Roofing Services Limited | Construction | 2023 |
| Dd-Accountancy Limited | Professional & scientific | 2025 |
| Ddanut Company Ltd | Construction | 2026 |
| Ddash Ltd | Transport & logistics | 2026 |
| DDL Security Limited | Administrative & support | 2016 |
| Ddle Holdings Ltd | Arts & recreation | 2023 |
| DDO Rail Services Limited | Construction | 2018 |
| DDP Protection Ltd | Administrative & support | 2024 |
| DDR Property Management Ltd | Real estate | 2020 |
| Ddsl Electric Limited | Energy | 2014 |
| DDX Engineering Ltd | Professional & scientific | 2025 |
| DE Luxe Miracle Pawel Hajduk Ltd | Transport & logistics | 2020 |
| DE WEY Distribution Limited | Wholesale & retail | 2001 |
| DE'ATH2TEST Ltd | Information & communication | 2025 |
| Deacon Residential Properties Ltd | Real estate | 2019 |
| Dead Rabbits Live Ltd | Arts & recreation | 2023 |
| Deadplace Ltd | Wholesale & retail | 2024 |
| Deakin Associates Limited | Health & social care | 2014 |
| Deakin Will Ltd | Information & communication | 2017 |
| Deal Support Limited | Professional & scientific | 2025 |
| Dealclub Limited | Professional & scientific | 2024 |
| Dealdashers Ltd | Wholesale & retail | 2025 |
| Dealstore I.B. Ltd | Wholesale & retail | 2023 |
| Dean & Dyball (Plymouth) Limited | Administrative & support | 1982 |
| Dean Court RTM Company Ltd | Households | 2006 |
| Dean Jones Training and Investigations Limited | Education | 2008 |
| Dean Road Property Management Co Limited | Real estate | 2007 |
| Deanfields Court Management Limited | Households | 2003 |
| Deanleigh Holdings Ltd | Arts & recreation | 2022 |
| Deanstone Property Ltd | Real estate | 2020 |
| Deanstone Property Two Limited | Real estate | 2021 |
| Dearden Motorcycles Limited | Wholesale & retail | 2007 |
| Death by Pinstripe Ltd | Manufacturing | 2019 |
| Debbie Afro Foods Limited | Wholesale & retail | 2025 |
| Deborah Sykes Limited | Real estate | 2023 |
| Debsandy Foundation Ltd | Health & social care | 2017 |
| Debsandy Icare Ltd | Administrative & support | 2024 |
| Deccan Trader Ltd | Wholesale & retail | 2023 |
| Decentralised Architectures Limited | Information & communication | 2023 |
| Deceptive Limited | Information & communication | 2023 |
| Decibel Systems Ltd | Extraterritorial | 2006 |
| Decima Music Ltd | Information & communication | 2024 |
| Decipher Consulting Recruitment Limited | Administrative & support | 2023 |
| Declan Dawkins Media Ltd | Professional & scientific | 2024 |
| Deco Team Ltd | Construction | 2017 |
| Dectech Limited | Construction | 2006 |
| Dedek Trans Ltd | Transport & logistics | 2019 |
| Dedicated to Detail Ltd | Wholesale & retail | 2020 |
| DEE Builder Housing Solutions Ltd | Real estate | 2025 |
| DEE Builder Ltd | Construction | 2019 |
| DEE Lite Ltd | Professional & scientific | 2015 |
| Deed Recruitment and Care Limited | Public administration | 2022 |
| Deejays Locker Limited | Arts & recreation | 2016 |
| Deenethorpe LLP | | 2011 |
| Deep Blue Design Ltd | Professional & scientific | 2016 |
| Deep Culture Ltd | Wholesale & retail | 2022 |
| Deep Down 'N' Dirty Cleaning Services Limited | Administrative & support | 2011 |
| Deep Fabrication Ltd | Professional & scientific | 2025 |
| Deep Finance Group Ltd | Information & communication | 2025 |
| Deep Space Systems Ltd | Information & communication | 2025 |
| Deep Tech Research Ltd | Other services | 2013 |
| Deepdene (Southampton) Management Company Limited | Households | 1988 |
| Deeplearn AI Ltd | Information & communication | 2023 |
| Deepwood Residents Company Limited | Households | 1987 |
| Deerleap Electrical Services Ltd | Construction | 2019 |
| Deers Leap Limited | Hospitality | 2016 |
| Deesland Property Company Limited | Real estate | 1961 |
| Definitive Acoustic Consultants Ltd | Professional & scientific | 2025 |
| Deft Engineering Ltd | Manufacturing | 2010 |