| DB FAB Services Limited | Manufacturing | 2017 |
| Digital Peanut Limited | Information & communication | 2017 |
| DJM Farming Ltd | Agriculture & fishing | 2014 |
| DMG Engineering Limited | Manufacturing | 2001 |
| Doolallys Entertainment Ltd | Information & communication | 2005 |
| Drew Murray Limited | Transport & logistics | 2017 |
| Durrand Property Ltd | Real estate | 2022 |
| DWS Services Ltd | Mining & quarrying | 2025 |
| DX Detect Ltd | Information & communication | 2026 |
| Ebenezer Leisure Limited | Wholesale & retail | 2004 |
| Elinayd Limited | Hospitality | 2025 |
| Elzytech Design Ltd | Manufacturing | 2013 |
| Emca Accountants Ltd | Professional & scientific | 2024 |
| Erridge Company Limited | Other services | 2021 |
| Essential Interiors Limited | Extraterritorial | 1995 |
| Excalibur Investments Ltd | Financial services | 2015 |
| Fableman's Highland Honey Ltd | Agriculture & fishing | 2024 |
| Fine Dine SCT Ltd | Hospitality | 2025 |
| Finished With Company - Project 24 Completed Ltd | Hospitality | 2017 |
| Finnscot Ltd | Hospitality | 2014 |
| Flavours (John O'Groats) Limited | Hospitality | 2012 |
| Forss Day Hire Ltd | Real estate | 2025 |
| Freswick Castle Ltd | Extraterritorial | 2007 |
| G Sinclair Painting & Decorating Ltd | Construction | 2017 |
| G.M.R. Plant Ltd. | Construction | 2003 |
| German Trade Kitchens Ltd | Manufacturing | 2023 |
| Gills Bay Small Plant & Tool Hire Ltd | Administrative & support | 2024 |
| GM Access and Rigging Ltd | Construction | 2017 |
| GMR Henderson Builders Ltd | Construction | 2008 |
| GOW Fishing Company Ltd | Agriculture & fishing | 2018 |
| Graham Begg Limited | Wholesale & retail | 1975 |
| Green & Cameron Limited | Construction | 1980 |
| Greentoft Farms Limited | Agriculture & fishing | 1975 |
| Grudgehouse Farming | | 1994 |
| Gunn C & I Systems Ltd | Professional & scientific | 2024 |
| Gunn Technical Services Limited | Mining & quarrying | 2014 |
| H&F Durrand Ltd | Professional & scientific | 2026 |
| Harrison Ecological Surveys Limited | Professional & scientific | 2021 |
| Hayfield Solution Ltd | Extraterritorial | 2013 |
| Headlines (Wick) Ltd | Other services | 2011 |
| Hearing and Sight Care | Health & social care | 2001 |
| Heat Centre (Wick) Limited | Energy | 2009 |
| Heggie Holdings Limited | Financial services | 2020 |
| Hemmings & Marshalsea Holdings Limited | Administrative & support | 2015 |
| Henderson Construction Limited | Construction | 2024 |
| Henderson Universal Services Ltd | Transport & logistics | 2006 |
| Hhcs (Wick) Limited | Hospitality | 2022 |
| High Street Chippy Ltd | Hospitality | 2022 |
| Highland Curry House Ltd | Hospitality | 2026 |
| Highland Hotels Limited | Hospitality | 2026 |
| Highland Insulation Services Ltd | Professional & scientific | 2012 |
| Highland NDT & Inspection Services Ltd | Professional & scientific | 2018 |
| Highland PAT & Power Ltd | Professional & scientific | 2025 |
| Highland Roofing & Gutter Services Ltd | Construction | 2025 |
| Hilltop Horses Ltd | Wholesale & retail | 2010 |
| Home Store Wick Ltd | Wholesale & retail | 2026 |
| Home-Start Caithness | Health & social care | 2005 |
| Horne Coaching Ltd | Other services | 2024 |
| Hudson House Lets Ltd | Hospitality | 2018 |
| Hugh Simpson (Contractors) Limited | Construction | 1979 |
| I Macphee Project Services Ltd | Construction | 2026 |
| I Saint Limited | Construction | 2020 |
| Iaccheri & Cabrelli Limited | Professional & scientific | 2016 |
| Inneswick Limited | Administrative & support | 1992 |
| J Ross Solutions Ltd | Construction | 2026 |
| J. Forestry Ltd | Construction | 2025 |
| J. Mccaughey Properties Ltd | Hospitality | 1979 |
| Jaar Property Ltd | Real estate | 2024 |
| Jackson Instrument Services Ltd | Administrative & support | 2007 |
| JAE Holdings Limited | Real estate | 2018 |
| JAM Systems Ltd | Manufacturing | 2013 |
| JB Tiles & Bathroom Solutions Limited | Construction | 2015 |
| Jenkins Plant & Tool Hire Limited | Construction | 2014 |
| JGB Property Lets Ltd | Hospitality | 2019 |
| Jimmy's Taxis Limited | Transport & logistics | 2025 |
| JLS Formwork Ltd | Construction | 2017 |
| John O'Groats Caravan & Camping Site Ltd | Hospitality | 2022 |
| John O'Groats Crafts Limited | Wholesale & retail | 1972 |
| John O'Groats Ferries Transport Ltd | Transport & logistics | 2019 |
| Johnston Electrical Services Ltd | Construction | 2026 |
| Joy Recruitment Services Limited | Administrative & support | 2022 |
| Karbon Lite Ltd | Agriculture & fishing | 2026 |
| Kayaking Adventures Limited | Arts & recreation | 2023 |
| Keiss Amenities Association | Other services | 2006 |
| Kelpie Environmental Consulting Limited | Professional & scientific | 2017 |
| Keystore Express (Wick) Limited | Wholesale & retail | 2014 |
| Keystore Hillhead Ltd | Wholesale & retail | 2019 |
| Killimster Farms | | 1991 |
| Kinetic Trade Services Ltd | Administrative & support | 2007 |
| Kman Groundworks Limited | Construction | 2016 |
| KP Technology (Holdings) Limited | Financial services | 2019 |
| KP Technology Ltd. | Manufacturing | 2000 |
| KR Highlandproperties Ltd | Real estate | 2025 |
| KSC Engineering Services Ltd | Extraterritorial | 2015 |
| KW1CK Deliveries Limited | Administrative & support | 2017 |
| KW1CK Getaways Ltd | Hospitality | 2026 |
| L D Crown Ltd | Hospitality | 2016 |
| L&S Highland Property Ltd | Real estate | 2020 |
| Laird & Clark Offshore Limited | Other services | 2012 |
| Langley Serviced Apartments Ltd | Real estate | 2024 |