| Shoplicity Limited | Information & communication | 2013 |
| Singleton's Corner Limited | Professional & scientific | 1989 |
| Sjbuk Consulting Limited | Professional & scientific | 2016 |
| SLJ (Whitehaven) Limited | Hospitality | 2005 |
| SLS Projects Limited | Other services | 2008 |
| Solar Storage UK Ltd | Construction | 2022 |
| Soleambera Ltd | Professional & scientific | 2014 |
| Solway Firth Imports Ltd | Professional & scientific | 2023 |
| Solway Petroleum Ltd | Wholesale & retail | 2026 |
| Solway Plastering Ltd | Construction | 2021 |
| Somersville Limited | Professional & scientific | 2006 |
| Soundwave Cumbria | Arts & recreation | 2007 |
| Spires Projects Limited | Hospitality | 2022 |
| SR Technical Solutions Limited | Professional & scientific | 2018 |
| ST Nicholas Court Management (Cumbria) Limited | Households | 2018 |
| Stamperlloyd Ltd | Wholesale & retail | 2010 |
| Stanaway's Ltd | Manufacturing | 2022 |
| Star Hair Style Cumbria Ltd | Other services | 2024 |
| Stash Technical Services Limited | Professional & scientific | 2008 |
| Steve Elkin Engineering Ltd | Professional & scientific | 2011 |
| Storm of UK Limited | Wholesale & retail | 2017 |
| Stratum NOW Limited | Information & communication | 2022 |
| Studio Yard Cumbria Ltd | Wholesale & retail | 2025 |
| Sunnyhill (Whitehaven) Limited | Hospitality | 2009 |
| Swift Shift Motors Ltd | Wholesale & retail | 2026 |
| Swood Lifting Devices Limited | Manufacturing | 2002 |
| Swrchy Ltd | Wholesale & retail | 2025 |
| T W T PUB Co Limited | Hospitality | 2024 |
| T W West Farms Limited | Agriculture & fishing | 2018 |
| T W West Ltd | Agriculture & fishing | 2003 |
| T. Archampong Limited | Health & social care | 2023 |
| T. Riley Construction Ltd | Construction | 2025 |
| Tania Hollerin T/A Moffats Limited | Hospitality | 2018 |
| Tantopia Ltd | Wholesale & retail | 2025 |
| Tapout Knockout JU Jitsu Ltd | Arts & recreation | 2026 |
| Tastygo Limited | Hospitality | 2024 |
| Tavistock Ltd | Agriculture & fishing | 2025 |
| Taz's Transport & Recovery Services Ltd | Transport & logistics | 2022 |
| TCM Engineering (Cumbria) Ltd | Other services | 2023 |
| TEACH4US Education Ltd | Administrative & support | 2024 |
| TEC Cumbria Limited | Professional & scientific | 2020 |
| Technology Consortia Limited | Professional & scientific | 1996 |
| THE Admiral's Home Limited | Real estate | 2026 |
| THE Beauty Haus Ltd | Other services | 2023 |
| THE Crafty Tortoise Ltd | Wholesale & retail | 2023 |
| THE Entrepreneurs Group Limited | Professional & scientific | 2018 |
| THE House of Swain CIC | Education | 2024 |
| THE Mansion Guesthouse Ltd | Hospitality | 2022 |
| THE Old Bank Management (Cumbria) Ltd | Construction | 2025 |
| THE Pour House Group Ltd | Hospitality | 2023 |
| THE Racers Edge Ltd | Wholesale & retail | 2024 |
| THE Shetland Sheep Society Limited | Other services | 2022 |
| THE Skin Edit Clinic Limited | Other services | 2023 |
| THE Strand Cumbria Ltd | Hospitality | 2018 |
| THE Summer Camp Ltd | Arts & recreation | 2025 |
| THE VET Whitehaven Cumbria Limited | Professional & scientific | 2023 |
| THE VET Whitehaven LLP | | 2021 |
| THE Whitehaven Foyer | Health & social care | 2009 |
| Thomas Paton Limited | Administrative & support | 2022 |
| Thomson Electrical & Energy Solutions Ltd | Construction | 2013 |
| Thomson's Developments & Property Services Limited | Real estate | 2019 |
| Three Lions Security & Training Limited | Administrative & support | 2018 |
| Threetunsrock Ltd | Hospitality | 2025 |
| Time to Change (West Cumbria) Project CIC | Health & social care | 2013 |
| Time to Share Bereavement Services CIC | Health & social care | 2020 |
| TJS Consultancy Limited | Professional & scientific | 2020 |
| TME Solutions Ltd | Construction | 2026 |
| TN Body & Paint Limited | Wholesale & retail | 2018 |
| Together WE CAN Create Ltd | Arts & recreation | 2023 |
| Tomlinson Engineering Services Ltd | Professional & scientific | 2024 |
| Tony Hopper Limited | Construction | 2002 |
| Tony Marks 28 Limited | Other services | 2013 |
| Tony Marks Egremount Ltd | Other services | 2019 |
| Tony Marks Hair Stylist Limited | Other services | 2013 |
| Tony Marks Main Street Cockermouth Ltd | Other services | 2012 |
| Tony Marks With Anya Graham Ltd | Other services | 2025 |
| Tony Marks With Rebecca Jones Limited | Other services | 2013 |
| Tony Sanders (Blacksmiths) Ltd | Manufacturing | 2003 |
| Top CUT Barber Cumbria Ltd | Other services | 2025 |
| Torver Accounting Limited | Professional & scientific | 2003 |
| Total Electrical Cumbria Ltd | Construction | 2022 |
| Total Property Cumbria Ltd | Real estate | 2024 |
| Tradesfolk Ltd | Wholesale & retail | 2018 |
| Training POD Ltd | Arts & recreation | 2024 |
| TSE Cocktail Bars Limited | Hospitality | 2023 |
| TTB Couriers Ltd | Transport & logistics | 2025 |
| TTL Racing Limited | Arts & recreation | 2006 |
| Turner Inspections Ltd | Professional & scientific | 2023 |
| Tutis Foster Care Ltd | Health & social care | 2014 |
| Twinsport Limited | Wholesale & retail | 2019 |
| Type IT Write Limited | Professional & scientific | 2017 |
| UK Furniture Ltd | Extraterritorial | 1996 |
| Ullswater Avenue 1963 Limited | Extraterritorial | 2014 |
| Ulomzy Care Company Limited | Health & social care | 2023 |
| Universe Nails Ltd | Other services | 2021 |
| Ursula-Wrmc Limited | Wholesale & retail | 2026 |
| Utopia Boardings Ltd | Other services | 2021 |
| Utopia Daycare and Grooming Ltd | Agriculture & fishing | 2025 |
| Vapes Direct 2 YOU Ltd | Wholesale & retail | 2025 |
| Vbuk Ltd | Arts & recreation | 2022 |