| Glasport BIO Limited | Professional & scientific | 2021 |
| Glass & Metal Construction 2021 Ltd | Construction | 2021 |
| Glass & Metal Construction Limited | Construction | 2012 |
| Glass Advisory Services Limited | Other services | 2011 |
| Glass Island View Management Company Limited | Households | 2022 |
| Glass Opticians Glengormley Limited | Wholesale & retail | 2025 |
| Glastonbury Investments Limited | Real estate | 2016 |
| Glastry Court Management Company Ltd | Extraterritorial | 2005 |
| Glasvey Group Limited | Administrative & support | 2025 |
| Glaze Digital Ltd | Information & communication | 2015 |
| Glazeclad UK Ltd | Construction | 2022 |
| GLD Design Ltd | Construction | 2021 |
| GLD Investments Ltd | Financial services | 2025 |
| GLD Ltd | Health & social care | 2012 |
| Gleam Auto Centre Ltd | Wholesale & retail | 2018 |
| Gleam Housekeeping NI Ltd | Administrative & support | 2025 |
| Gleam Property Services Ltd | Administrative & support | 2010 |
| Gleann NA Habhann Ltd | Hospitality | 2024 |
| Glebe Farm Balteagh Limited | Agriculture & fishing | 2025 |
| Glebe House Development Management Company Limited | Households | 2007 |
| Glebe House Holdings | Financial services | 2024 |
| Glem Ltd | Other services | 2002 |
| Glem Properties Ltd | Real estate | 2019 |
| Glen Arthur Lodge Limited | Real estate | 1985 |
| Glen Catering Ltd | Hospitality | 2023 |
| Glen Construction and Building Limited | Construction | 1993 |
| Glen Devon Property Limited | Real estate | 2016 |
| Glen Manor (Hightown Road) Management Company Limited | Households | 2021 |
| Glen Mini-Bus Services Ltd | Transport & logistics | 2010 |
| Glen Park Belfast Ltd | Hospitality | 2023 |
| Glen Road Retail Holdings Limited | Wholesale & retail | 2023 |
| Glenafton Care Home Limited | Health & social care | 2005 |
| Glenalpin Street Limited | Hospitality | 2010 |
| Glenandco Ltd | Real estate | 2024 |
| Glenard Estates Limited | | 1935 |
| Glenard Plant (NI) Limited | Administrative & support | 2019 |
| Glenarden Holdings Limited | Financial services | 1962 |
| Glenarn Holdings Limited | Agriculture & fishing | 2015 |
| Glenavna Management Company Limited | Households | 2009 |
| Glenavy Engineering Limited | Manufacturing | 2022 |
| Glenavy Group Ltd | Health & social care | 2017 |
| Glenbank Apartments Limited | Households | 1981 |
| Glenbank Estates Limited | Professional & scientific | 1983 |
| Glenbank Holdings Limited | Real estate | 1989 |
| Glenbeigh Estates Ltd | Real estate | 2016 |
| Glenbrae Developments Limited | Real estate | 2007 |
| Glenbrae Enterprises Limited | Real estate | 2014 |
| Glenburn Court (Larne) Management Limited | Households | 2020 |
| Glenburn Court Limited | Extraterritorial | 1985 |
| Glenburn Ford Limited | Households | 1996 |
| Glenburn Manor Limited | Households | 2006 |
| Glenburn Veterinary Centre Limited | Extraterritorial | 2007 |
| Glencairn Apartments Management Limited | Extraterritorial | 2008 |
| Glencairn Community Project | Arts & recreation | 2017 |
| Glencollyer Street Management Ltd | Households | 2023 |
| Glencorr Homes Limited | Real estate | 2012 |
| Glendale 3 Ltd | Real estate | 2025 |
| Glendale Court Apartments Limited | Households | 2006 |
| Glendale Property Investments Limited | Real estate | 2023 |
| Glendale Quays Limited | Wholesale & retail | 2018 |
| Glendale Retail Holdco Limited | Financial services | 2023 |
| Glendale Retail Ltd | Wholesale & retail | 1999 |
| Glendale Stores Limited | Wholesale & retail | 2004 |
| Glendinning Mcleish & Co Limited | Real estate | 1898 |
| Glendoan Properties Ltd | Real estate | 2017 |
| Glendor Holdings Ltd | Financial services | 2022 |
| Glendromside Investment Unlimited | Financial services | 2021 |
| Glendun Sales Ltd | Wholesale & retail | 2025 |
| Glendunne Limited | Households | 2004 |
| Glenford Grove Ltd | Households | 2016 |
| Glengall Management Company Ltd | Households | 2004 |
| Glengoland Avenue Limited | Extraterritorial | 2015 |
| Glenhill Merchants Limited | Wholesale & retail | 2002 |
| Glenhill Park Management Company Limited | Households | 2004 |
| Glenkeen Limited | Real estate | 2017 |
| Glenlyon Gate Developments Limited | Construction | 2025 |
| Glenmac Contracts Ltd | Construction | 2020 |
| Glenmachan Park Management Company Limited | Households | 2020 |
| Glenmachan Tower Limited | Health & social care | 2025 |
| Glenmayne Group Limited | Financial services | 2018 |
| Glenmayne Limited | Administrative & support | 2013 |
| Glenmillan Press Ltd | Information & communication | 2025 |
| Glenmore Generation Limited | Energy | 2015 |
| Glenmore House Management Company Limited | Households | 1998 |
| Glenmorne Consultants Limited | Professional & scientific | 2002 |
| Glenmount Village Management Company Ltd | Extraterritorial | 2003 |
| Glenmurray Court Management Company Limited | Households | 2006 |
| Glenn Dair Interiors Limited | Construction | 2025 |
| Glenn Irwin Ltd | Arts & recreation | 2018 |
| Glenoak Grange Meadows Management Co Ltd | Households | 2017 |
| Glenovation Limited | Information & communication | 2006 |
| Glenpatrick Limited | Agriculture & fishing | 2011 |
| Glenpatrick Sport Horses Ltd | Agriculture & fishing | 2014 |
| Glens of Antrim Crisps Ltd | Manufacturing | 2025 |
| Glens of Antrim Group Limited | Financial services | 2025 |
| Glens of Antrim Investments Limited | Financial services | 2025 |
| Glens of Antrim Potatoes Limited | Wholesale & retail | 1996 |
| Glenside Restoration Company Limited | Water & waste | 2015 |
| Glenstal Foods UK Limited | Professional & scientific | 2025 |
| Glenthorn Joinery Limited | Construction | 2016 |