| Imperial Distillers Co. Limited | Wholesale & retail | 1987 |
| IN 2 Technology Limited | Information & communication | 2003 |
| International Sport Horses Limited | Agriculture & fishing | 2018 |
| International Turf Ltd | Administrative & support | 2022 |
| Invergeldie Limited | Hospitality | 2007 |
| Ionic Energy Limited | Wholesale & retail | 2011 |
| Isabella M. Deas Limited | Construction | 1969 |
| IVY James Ltd | Hospitality | 2024 |
| J W Thomson Ltd | Manufacturing | 2012 |
| J&M Vista Co Ltd. | Hospitality | 2020 |
| J.B.W. Smith (Agricultural Division) Limited | Wholesale & retail | 1969 |
| JA Golf Travel Ltd | Administrative & support | 2026 |
| Jack O Bryans Limited | Hospitality | 2018 |
| Jackson Knight Ltd | Construction | 2026 |
| Jagger Properties Limited | Hospitality | 2025 |
| Jaklog Ltd | Professional & scientific | 2015 |
| Jannettas Gelateria Ltd | Wholesale & retail | 2014 |
| Jasmine Thai Retreat Ltd | Health & social care | 2024 |
| JBD Fife Ltd | Wholesale & retail | 2023 |
| Jenteq Technologies Ltd | Professional & scientific | 2025 |
| JET Taxi ST Andrews Ltd | Transport & logistics | 2026 |
| JGN Transport Company Ltd | Transport & logistics | 2025 |
| JM Electrical Green Energy Limited | Construction | 2023 |
| JMJ Joiners & Developers Ltd | Construction | 2018 |
| JNJ Bathrooms Limited | Wholesale & retail | 2003 |
| John Beattie Accountancy & Audit Services Limited | Professional & scientific | 2008 |
| John Birrell & Son(St.Andrews)Limited | Wholesale & retail | 1976 |
| Joinery & Construction Supplies Ltd | Wholesale & retail | 2009 |
| JP Statements Limited | Professional & scientific | 2022 |
| Jurassic Bark Dog Grooming Ltd | Other services | 2022 |
| K.H.K Group (MCR) Limited | Administrative & support | 2023 |
| Kartel Watches Limited | Wholesale & retail | 2016 |
| KB Store (ST Andrews) Ltd | Wholesale & retail | 2010 |
| KH Trading of Balmullo Ltd | Hospitality | 2015 |
| Kilduncan (Holdings) Ltd | Administrative & support | 2008 |
| Kinburn Landscaping Limited | Administrative & support | 2002 |
| Kinfern Holdings Limited | Financial services | 2025 |
| Kingdom Cardiology Ltd | Real estate | 2023 |
| Kingsbarns Community Development Trust | Professional & scientific | 2012 |
| Kinkell Byre Limited | Real estate | 2019 |
| Kinness Consult Ltd | Professional & scientific | 2025 |
| Kinnessburn Ltd | Information & communication | 2023 |
| KM ST. Andrews Ltd | Hospitality | 2021 |
| Kthai ST. Andrews Ltd | Hospitality | 2016 |
| Kwad Leisure Limited | Real estate | 2000 |
| KY16 Spirits Limited | Manufacturing | 2020 |
| L&C Lettings Ltd | Real estate | 2025 |
| Ladarena Logistics LP | | 2015 |
| Langate Management LP | | 2015 |
| LATITUDE74 Offshore Survey Ltd | Professional & scientific | 2025 |
| Lawson & Thompson Ltd | Households | 2013 |
| Lawson & Thompson Property Services Ltd | Real estate | 2017 |
| Lawson Hospitality Group Limited | Real estate | 2025 |
| Lawson Property Group Limited | Real estate | 2018 |
| Lclg Properties Ltd | Real estate | 2024 |
| Learning Time Ltd | Professional & scientific | 2013 |
| Leima Corporation LP | | 2015 |
| Leuchars Glazing Limited | Construction | 2004 |
| Level 3 Rope Access Limited | Professional & scientific | 2018 |
| Leven Taxis Ltd | Transport & logistics | 2024 |
| Library Homes Ltd | Real estate | 2024 |
| Lighthouse 783 Ltd | Mining & quarrying | 2023 |
| Links Golf ST. Andrews Holdings Limited | Financial services | 2023 |
| Links International Golf Academy Ltd | Administrative & support | 2024 |
| Links Luxe Travel Ltd | Administrative & support | 2026 |
| Links Transfer and Tour Limited | Transport & logistics | 2025 |
| Linksman Scotland Ltd | Wholesale & retail | 2019 |
| Little Golden PIG Limited | Real estate | 2019 |
| Lochaber Funeral Plans Ltd | Financial services | 2014 |
| Logan Trading Company Limited | Agriculture & fishing | 1994 |
| Longin Corp. LP | | 2015 |
| Longstaffe International Limited | Professional & scientific | 2022 |
| Love 4 ALL Property Ltd | Real estate | 2026 |
| Love Travel Adventures Ltd | Administrative & support | 2021 |
| Luceo Training Ltd | Professional & scientific | 2017 |
| M & a Nethergate Ltd | Hospitality | 2025 |
| M&E Marine Consultants Limited | Administrative & support | 2014 |
| M. Dinsley Tech Services Limited | Manufacturing | 2017 |
| M.N.S. (Brackmont) Quarry Limited | Professional & scientific | 1993 |
| Macleod Plumbing & Heating Limited | Construction | 2007 |
| Mafel Limited | Real estate | 2022 |
| Marbelle Properties Ltd | Real estate | 2026 |
| Marcscott Consulting Ltd. | Professional & scientific | 2010 |
| Mardal Limited | Hospitality | 2011 |
| Marine Services Group Management Company LP | | 2015 |
| Marivate Limited | Agriculture & fishing | 2022 |
| Mason Property Consultants (ST Andrews) Ltd | Real estate | 2021 |
| Maxin Fife Limited | Hospitality | 2021 |
| Mayra Corp. LP | | 2015 |
| MC Link Ltd. | Professional & scientific | 2002 |
| MC Safety Services Ltd | Professional & scientific | 2021 |
| Mclaren Products W/A Ltd | Wholesale & retail | 2023 |
| Medgrowth Partners Ltd | Professional & scientific | 2026 |
| Media Pass LP | | 2015 |
| Melwill LP | | 2015 |
| Mena Development Valley Limited | Professional & scientific | 2024 |
| MGD Estates Limited | Real estate | 2017 |
| Milk Tray MAN Ltd | Administrative & support | 2021 |
| Millers Tale Ltd | Administrative & support | 2017 |
| Milton of Leuchars Limited | Agriculture & fishing | 2014 |