| Norpax Ltd | Transport & logistics | 2023 |
| North Bank Contracts Limited | Construction | 2007 |
| North Curve Ltd | Construction | 2018 |
| North of Scotland Bonding Company Ltd | Administrative & support | 2022 |
| North of Scotland Distilling Company Limited | Wholesale & retail | 1995 |
| North of Scotland Financial Services Ltd | Professional & scientific | 2020 |
| North Parts Ltd | Wholesale & retail | 2024 |
| North West Roof Services Limited | Construction | 2023 |
| Northern Commercials (Scotland) Ltd | Wholesale & retail | 2003 |
| Northwind (Scotland) Limited | Professional & scientific | 2011 |
| Nourish & Move Fitness & Nutrition Ltd | Manufacturing | 2025 |
| Nova TAN Ltd | Other services | 2025 |
| Nova-Castrum Property Management Ltd | Real estate | 2020 |
| Novizora Services Limited | Administrative & support | 2025 |
| NOW Slim Limited | Health & social care | 2004 |
| NR Fastfood Ltd | Hospitality | 2026 |
| Nrggrab Ltd | Information & communication | 2025 |
| NS Bookkeeping Services Ltd | Professional & scientific | 2020 |
| Numeric Lint Ltd | Information & communication | 2026 |
| Nxgen Global Limited | Administrative & support | 2020 |
| NY Homes & Properties Ltd | Real estate | 2024 |
| O'Hagan Builders & Joiners Limited | Construction | 2006 |
| O.C.O. Group Limited | Financial services | 2025 |
| O.C.O. West END Limited | Hospitality | 2001 |
| Oak Properties (Scot) Ltd | Real estate | 2022 |
| Oaklea Hospitality Ltd | Other services | 2023 |
| Oakshaw Apartments Limited | Real estate | 2024 |
| Oakshaw Contracting Limited | Financial services | 2015 |
| Oakshaw Residence Limited | Real estate | 2024 |
| Oakwood Projects Ltd | Construction | 2022 |
| Ocean Plastic Pots Ltd | Extraterritorial | 2022 |
| Oceania Rentals Limited | Real estate | 2001 |
| Ochilview Limited | Construction | 2018 |
| Ocolate Ltd | Information & communication | 2026 |
| OFF & on IT Ltd | Information & communication | 2021 |
| OFF the Chain Rigging Limited | Professional & scientific | 2024 |
| Offensive Media Ltd | Professional & scientific | 2011 |
| Office File Storage (Paisley) Ltd | Administrative & support | 2016 |
| Offshore Services Ltd | Mining & quarrying | 2020 |
| OGO Services Ltd | Real estate | 2026 |
| OH Flick Productions Ltd | Information & communication | 2021 |
| OH My Gelato Limited | Hospitality | 2021 |
| Ohkay Limited | Other services | 2026 |
| OHT Technical Management Ltd | Transport & logistics | 2020 |
| Olad Automobile Sales Limited | Wholesale & retail | 2022 |
| Olan Meows Ltd | Wholesale & retail | 2026 |
| Olden Goldies (Paisley) Ltd | Other services | 2022 |
| Olive and Thistle Productions Limited | Arts & recreation | 2017 |
| Oliver's Highland Pet Crematorium Ltd | Other services | 2025 |
| Olivia Interiors Ltd | Other services | 2017 |
| Omar Jammeh Limited | Health & social care | 2022 |
| Ombrex 360 Ltd | Wholesale & retail | 2026 |
| Omnius Group Holdings Limited | Administrative & support | 2008 |
| Omnius Propshafts Ltd | Manufacturing | 2012 |
| ON Site Training and Services Ltd | Administrative & support | 2022 |
| ON Target Fitness Ltd | Arts & recreation | 2019 |
| One Cove Road Ltd | Hospitality | 2016 |
| One Step Beyond Consultancy Ltd | Professional & scientific | 2024 |
| One Unit LLP | | 2007 |
| ONE44 Properties Limited | Real estate | 2020 |
| Oneandthree Design Limited | Professional & scientific | 2019 |
| Onelec Limited | Construction | 2007 |
| Onemat Limited | Wholesale & retail | 2025 |
| Onlybins Cleaning Service Ltd | Administrative & support | 2025 |
| Oomi’S Cards Ltd | Wholesale & retail | 2026 |
| Open Play Initiative CIC | Arts & recreation | 2026 |
| Open Road Motorhomes Limited | Hospitality | 2007 |
| Opporchancity Ltd | Administrative & support | 2009 |
| Opportunity Knocks Ltd | Real estate | 2022 |
| Optima Concepts Limited | Information & communication | 2013 |
| Optimal Construction Solutions Limited | Administrative & support | 2015 |
| Optimal Group Holdings Ltd | Administrative & support | 2015 |
| Optimus Coatings Ltd | Construction | 2015 |
| Optimus Decorating Services Ltd | Construction | 2023 |
| Optimus Flooring Services Ltd | Construction | 2023 |
| Optix Glazing Ltd | Construction | 2007 |
| Opus IQ Ltd | Information & communication | 2001 |
| Orbus Building Services Limited | Wholesale & retail | 2005 |
| Orbus Traffic Management Ltd | Construction | 2019 |
| ORC Geomatics Limited | Professional & scientific | 2019 |
| Orca & Sons Ltd | Real estate | 2021 |
| Orchard Clinic (Paisley) Ltd | Health & social care | 2019 |
| Orchard Grove Nurseries Limited | Administrative & support | 2004 |
| Orchard Street Tree Surgeons Ltd | Professional & scientific | 2011 |
| Orghack Ltd | Professional & scientific | 2023 |
| Origin Commercial Maintenance Ltd | Administrative & support | 2026 |
| Origin Construction Contracts Ltd | Construction | 2022 |
| OSA Pipefitters Limited | Manufacturing | 2019 |
| Osaka Trading Ltd | Wholesale & retail | 2019 |
| Osakiken Property Limited | Households | 2024 |
| Oscar Henderson Ltd. | Hospitality | 2012 |
| Ospirals Ltd | Information & communication | 2011 |
| Otasco Ltd | Transport & logistics | 2024 |
| Othen Properties Ltd | Real estate | 2025 |
| Ourobeads Ltd | Wholesale & retail | 2025 |
| OUT of Debt Ltd | Professional & scientific | 2025 |
| OUT of Hours (AM) Ltd | Administrative & support | 2009 |
| Outside & in Limited | Other services | 2024 |
| OVA Essentials Ltd | Wholesale & retail | 2019 |
| Own Energy (UK) Limited | Extraterritorial | 2018 |