| Dcmom Holdings Ltd | Hospitality | 2022 |
| Decoflora Limited | Wholesale & retail | 2009 |
| Decus Ltd | Information & communication | 2025 |
| Delicious (Workington) Limited | Hospitality | 2019 |
| Delicious Grill Workington Ltd | Hospitality | 2025 |
| Delta Electrical Cumbria Ltd | Construction | 2021 |
| Demco Consulting Limited | Professional & scientific | 2025 |
| Denala Holdings Ltd | Real estate | 2023 |
| DEO Construction Ltd | Construction | 2020 |
| DEO Properties Ltd | Real estate | 2016 |
| Derwent Court (Cockermouth) Limited | Households | 1997 |
| Derwent Croft Properties Ltd | Real estate | 2024 |
| Derwent Electronics Ltd | Manufacturing | 2023 |
| Derwent GAS Ltd | Construction | 2016 |
| Derwent Management Services (Cumbria) Ltd | Professional & scientific | 2002 |
| Derwent Prints Ltd | Wholesale & retail | 2026 |
| Derwent Property Group Ltd | Construction | 2026 |
| District Scaffolding Solutions Cumbria Ltd | Construction | 2026 |
| DJG Food Inspection Services Limited | Hospitality | 2013 |
| DKS Caravan Centre Limited | Manufacturing | 2019 |
| DMB Property Improvements Ltd | Real estate | 2025 |
| DMP Vehicle Repairs Ltd | Wholesale & retail | 2026 |
| Dobies Cumbria Finance Limited | Financial services | 2013 |
| Dobies Cumbria Motors Limited | Wholesale & retail | 2004 |
| Dobies Cumbria Properties Limited | Real estate | 2011 |
| Dobies Cumbria Washington Central Hotel Limited | Hospitality | 2004 |
| Dobies Cumbria Workington Limited | Wholesale & retail | 2004 |
| Dobinson Holdings Ltd | Financial services | 2023 |
| Dobinson Properties Ltd | Real estate | 2023 |
| Dog House Catering Limited | Hospitality | 2026 |
| Dolly Monroes Limited | Real estate | 2022 |
| Dominic Hughes Delivery Logistics Ltd | Transport & logistics | 2026 |
| Double Happiness Takeaway Limited | Hospitality | 2019 |
| Doubletree Financial Services Limited | Administrative & support | 2009 |
| Dowson Blades Limited | Manufacturing | 1986 |
| DPF Cleaning Services (Cumbria) Limited | Wholesale & retail | 2025 |
| Drainline Cumbria Ltd | Administrative & support | 2025 |
| DRB Lifting Ltd | Construction | 2024 |
| Dream Clean Cumbria Ltd | Administrative & support | 2026 |
| Dreamtime (Cumbria) Ltd | Other services | 2019 |
| Dreamwood Lodge Limited | Hospitality | 2025 |
| Drmc Welding and Pipe Fitting Service Ltd | Manufacturing | 2026 |
| DTL Developments Limited | Real estate | 2020 |
| Dustin Front Limited | Arts & recreation | 2021 |
| DUZ Trading Limited | Wholesale & retail | 2019 |
| DWD Consulting Limited | Professional & scientific | 2019 |
| E B Lamb Limited | Wholesale & retail | 2002 |
| E Mcdougall T/A Breakthrough Hypnotherapy Limited | Health & social care | 2026 |
| Ealing Partners Ltd | Professional & scientific | 2020 |
| East END Competitions Ltd | Arts & recreation | 2024 |
| Eastern Spices Workington Ltd | Hospitality | 2024 |
| EAT Train Live Ltd | Arts & recreation | 2017 |
| ECM Cumbria Holdings Ltd | Financial services | 2023 |
| ED Roberts Limited | Construction | 1997 |
| Eden (Workington) Limited | Hospitality | 2019 |
| Edinburgh Wood Fuel Limited | Wholesale & retail | 2014 |
| Edmond O'Fee Ltd | Transport & logistics | 2017 |
| Edward J Grice Wealth Management Ltd | Financial services | 2014 |
| EFT Agricultural Services Ltd | Agriculture & fishing | 2025 |
| Egremont Pizza Ltd | Hospitality | 2025 |
| Eilbeck Developments Limited | Construction | 2006 |
| EJ Distribution Ltd | Wholesale & retail | 2016 |
| EJJ Properties Limited | Real estate | 2012 |
| EK Consultancy Cumbria Ltd | Professional & scientific | 2025 |
| Electric Beach (UK) Limited | Other services | 2012 |
| Electric Soup Nightclub Ltd | Administrative & support | 2019 |
| Elephant Feathers Ltd | Professional & scientific | 2003 |
| Eleria Media Ltd | Manufacturing | 2023 |
| Elite Parking (Whitehaven) Limited | Transport & logistics | 2019 |
| Elliott Linford Civil Engineering Ltd | Construction | 2024 |
| Elsaf Cumbria Ltd | Wholesale & retail | 2022 |
| Ember AI Ltd | Education | 2026 |
| Emma Bakes Limited | Hospitality | 2020 |
| Emmas Food HUT Ltd | Hospitality | 2024 |
| Empire Gym Supplements Limited | Wholesale & retail | 2024 |
| Empire Sports Performance Limited | Education | 2018 |
| Emrys Hair Studio Limited | Other services | 2024 |
| EN Property Holdings Ltd | Real estate | 2026 |
| Energy Coast Laundry Ltd | Other services | 2018 |
| Energy Coast UTC | Education | 2012 |
| Energy Efficient Window Systems Limited | Construction | 2021 |
| Energywise Plumbing & Heating Limited | Construction | 2013 |
| Engineering Commercial Consultants Limited | Professional & scientific | 2007 |
| Engineering Paddler Designs Limited | Professional & scientific | 2004 |
| EOS Extensions Ltd | Other services | 2024 |
| EOS Property Developments Ltd | Real estate | 2026 |
| EPC LEE Limited | Administrative & support | 2025 |
| ETR Properties Ltd | Real estate | 2020 |
| Everlong QA Limited | Professional & scientific | 2019 |
| Everything E-Shop Ltd | Wholesale & retail | 2023 |
| Evolved Trading Ltd | Wholesale & retail | 2023 |
| Ewan Vickers Ltd | Construction | 2013 |
| F G Estates Limited | Construction | 2015 |
| F. Younghusband & Sons Limited | Construction | 2008 |
| Fave Kravez Ltd | Wholesale & retail | 2023 |
| Fedwen Properties Limited | Real estate | 2024 |
| Fellside Homes & Renovations Ltd | Construction | 2023 |
| Fellside Properties (Southport) Limited | Real estate | 2026 |
| Fencing, Decking and Garden Services (Cumbria) Limited | Administrative & support | 2019 |
| Fieldco Ltd | Hospitality | 2019 |