| Hamnavoe Technical Services Ltd | Other services | 2026 |
| Harbour FRY (Kirkwall) Ltd. | Wholesale & retail | 2003 |
| Harcus Law Ltd | Professional & scientific | 2018 |
| Hatston Ltd | Wholesale & retail | 2017 |
| Hatston Veterinary Centre Limited | Professional & scientific | 2008 |
| Heat Orkney Limited | Construction | 2024 |
| Heat Orkney Property Limited | Manufacturing | 2010 |
| Heddle Construction Limited | Construction | 2013 |
| Heddle Ltd | Administrative & support | 2023 |
| Hest Wind Power Limited | Energy | 2012 |
| Heward’S Register Limited | Agriculture & fishing | 2021 |
| Highlands & Islands Sustainable Aviation Limited | Transport & logistics | 2023 |
| Historic Orkney Ltd | Transport & logistics | 2025 |
| Holme Properties Orkney Limited | Hospitality | 2004 |
| I & a Hume Limited | Wholesale & retail | 2013 |
| I Repair Orkney Limited | Other services | 2021 |
| Iain Laird Events & Security Ltd | Administrative & support | 2021 |
| ICK (Orkney) Ltd | Wholesale & retail | 2023 |
| Igtl Technology Ltd | Professional & scientific | 2010 |
| Illustrious Fishing Ltd. | Agriculture & fishing | 2014 |
| Image Orkney Ltd | Other services | 2018 |
| Innovation Centre - Orkney Ltd | Real estate | 2021 |
| Irvine Properties Scotland LLP | | 2025 |
| Island Hygge Limited | Health & social care | 2020 |
| J & R Foubister Limited | Wholesale & retail | 2008 |
| J & W Tait Limited | Agriculture & fishing | 1954 |
| J Breck Engineering Ltd | Manufacturing | 2024 |
| J F MAC Services Ltd | Professional & scientific | 2012 |
| J Mcgregor Builder (Orkney) Limited | Construction | 2020 |
| J Ross Engineering Ltd | Wholesale & retail | 2025 |
| J S C Marine Ltd | Agriculture & fishing | 2026 |
| J Thomson Services Ltd | Professional & scientific | 2022 |
| James Flett & Sons (Orkney) Limited | Real estate | 1941 |
| JLB Hire Ltd | Construction | 2022 |
| John G Shearer & Sons | Wholesale & retail | 1991 |
| John G. Corse Funeral Directors Limited | Other services | 2005 |
| John Jolly (1978) Limited | Transport & logistics | 1978 |
| John Mcgregor Holiday Homes Limited | Construction | 2016 |
| John Scott & SON (Farmers) Limited | Agriculture & fishing | 2006 |
| Johnston Properties (Orkney) Limited | Real estate | 2019 |
| JT Motors Orkney Ltd | Wholesale & retail | 2022 |
| Judith Glue Limited | Wholesale & retail | 2015 |
| K Allan Properties Ltd | Real estate | 2021 |
| KDM Fluid Power Ltd | Administrative & support | 2015 |
| Kelvin Estates Limited | Real estate | 2015 |
| Kelvin Property Services Limited | Real estate | 2006 |
| Kenneth C Findlay & Sons Limited | Construction | 2015 |
| Kenny Foulis Gardening Services Ltd | Administrative & support | 2018 |
| Keyvision Security Ltd | Administrative & support | 2025 |
| Kirkjuvagr Limited | Real estate | 2004 |
| Kirkwall BID Limited | Other services | 2013 |
| Kirkwall Lets Ltd | Real estate | 2021 |
| Klostathr (Drumsheugh) Holdings Ltd | Real estate | 2025 |
| Kontinentz Media Ltd | Information & communication | 2025 |
| KT Sports (Orkney) Limited | Wholesale & retail | 2009 |
| KTM Orkney Developments Ltd | Real estate | 2026 |
| L Harray Limited | Hospitality | 2018 |
| Laird Creations Ltd | Information & communication | 2019 |
| Lastmile ID Ltd | Information & communication | 2026 |
| Latitude Wealth Management (Scotland) Ltd | Professional & scientific | 2019 |
| Latitudex Marine Limited | Transport & logistics | 2021 |
| Leask Diving Limited | Manufacturing | 2016 |
| Leask Marine Limited | Professional & scientific | 2005 |
| Licenced to Clean Limited | Administrative & support | 2002 |
| Life Church Orkney Limited | Other services | 2003 |
| Lin's Takeaway Limited | Hospitality | 2008 |
| Littlejohn Removals Limited | Transport & logistics | 2016 |
| Livingstone Environmental Limited | Administrative & support | 2009 |
| Lochland Developments Ltd | Construction | 2006 |
| Longship Crafts Ltd | Manufacturing | 2017 |
| Lows Orkney Limited | Real estate | 2010 |
| Lucy Crowe Limited | Professional & scientific | 2022 |
| Macfoys Ltd | Manufacturing | 2024 |
| Magallanes FOW 1 Limited | Professional & scientific | 2023 |
| Magallanes FOW 3 Limited | Professional & scientific | 2025 |
| Magallanes Tidal Energy Ltd | Professional & scientific | 2020 |
| Mainstay North Sea Limited | Mining & quarrying | 2002 |
| Major Comps Ltd | Arts & recreation | 2021 |
| Marine Deep Ltd | Information & communication | 2020 |
| Mcadie & Reeve Limited | Transport & logistics | 2007 |
| Mclennan Energy Limited | Energy | 2013 |
| MDC Electrical Ltd | Construction | 2022 |
| Michael Butler Ltd | Health & social care | 2022 |
| Mixxyl Limited | Information & communication | 2023 |
| Moonshine Candle Co. Ltd | Manufacturing | 2025 |
| Morcon Energy Services Limited | Other services | 2006 |
| Mounthoolie Holdings Limited | Financial services | 2023 |
| Movement Coffee Limited | Hospitality | 2026 |
| MRS Chips Ltd | Hospitality | 2021 |
| Ms&A Consulting Limited | Mining & quarrying | 2011 |
| Msdex Inspections Ltd | Manufacturing | 2019 |
| Munro's Garage (Orkney) Limited | Professional & scientific | 2017 |
| MW Electrical Orkney Ltd | Manufacturing | 2024 |
| Neom Consulting Ltd | Professional & scientific | 2020 |
| Nepenthean Solutions Ltd | Professional & scientific | 2025 |
| Newton Research Limited | Information & communication | 2022 |
| Nick Symonds Limited | Construction | 2005 |
| Niteo Development Ltd | Professional & scientific | 2019 |
| Nordhavn Properties Ltd | Real estate | 2026 |
| Norsepharm Limited | Wholesale & retail | 2009 |