| Gabriella Bridal Ltd | Wholesale & retail | 2016 |
| Gabs Heating and Plumbing Solutions Limited | Construction | 2018 |
| Gabted Limited | Other services | 2014 |
| Gaby & David Ltd | Transport & logistics | 2025 |
| Gaby Mika Ltd | Transport & logistics | 2018 |
| GAF Cleaning Services Ltd | Administrative & support | 2020 |
| GAF Logistics Limited | Transport & logistics | 2018 |
| Gaia Transport Limited | Transport & logistics | 2022 |
| Gains Procurement Services Limited | Real estate | 2024 |
| Gaio Transport Ltd | Transport & logistics | 2025 |
| GAJ Foods Ltd | Wholesale & retail | 2025 |
| Gajservices Ltd | Administrative & support | 2025 |
| Gala Freehouses Ltd | Wholesale & retail | 2014 |
| Galafall (NO 2) Limited | Households | 1993 |
| Galahad Design Limited | Information & communication | 2024 |
| Galaxy Online School Ltd | Education | 2020 |
| Galaxy Tiles and Bathrooms Limited | Wholesale & retail | 2021 |
| Galexy Corp Associates Ltd | Administrative & support | 2011 |
| Galigali Limited | Transport & logistics | 2024 |
| Galil Ltd | Wholesale & retail | 2022 |
| Galis Konga Ltd | Health & social care | 2023 |
| Galleries (Fashions) Limited | Wholesale & retail | 1973 |
| Galloway GB Holding Ltd | Financial services | 2025 |
| Galtyview Properties Limited | Real estate | 2019 |
| Galvin Management Limited | Information & communication | 2005 |
| Gamble Drone Services Limited | Professional & scientific | 2026 |
| Gamc Management Limited | Households | 1988 |
| Game on Limited | Financial services | 2008 |
| Gamer Clothing Ltd. | Wholesale & retail | 2019 |
| Games From Afar Limited | Manufacturing | 2012 |
| Games Land Limited | Information & communication | 2024 |
| Gammer Worldwide Limited | Arts & recreation | 2023 |
| Gangar Express Limited | Transport & logistics | 2021 |
| Ganymede Consulting Ltd | Professional & scientific | 2024 |
| Ganzi Nannying Agency Ltd | Health & social care | 2023 |
| GAP Guitars Ltd | Wholesale & retail | 2011 |
| Gapardo Ltd | Arts & recreation | 2026 |
| Gapinsure Limited | Financial services | 2021 |
| Gapp Capital Limited | Administrative & support | 2022 |
| Gapp-Partners Ltd | Administrative & support | 2021 |
| Gaptooth Konsult IT Ltd | Wholesale & retail | 2020 |
| Garagista Ltd | Transport & logistics | 2023 |
| Garbuz Construction Ltd | Construction | 2019 |
| Garden Machines (Northampton) Ltd. | Administrative & support | 1967 |
| Gardener Northampton Ltd | Wholesale & retail | 2021 |
| Gardenforce Driveways Limited | Construction | 2020 |
| Gardenforce Landscapes Limited | Administrative & support | 2016 |
| Gardening for YEW Ltd | Administrative & support | 2023 |
| Gardenkind Ltd | Administrative & support | 2025 |
| Gardi Industrial Services Ltd. | Professional & scientific | 2001 |
| Gardner Fencing & Firewood Limited | Construction | 2018 |
| Gardners Bakery Limited | Wholesale & retail | 2003 |
| Gareth Bath Ltd | Professional & scientific | 2026 |
| Garnim Nexus Ltd | Other services | 2025 |
| Garrod and Company (Developments) Limited | Real estate | 1985 |
| Garshana Limited | Wholesale & retail | 2014 |
| Garuda Investments Limited | Real estate | 2024 |
| Garway-Heath Ltd | Health & social care | 2010 |
| Gary Boyd Ltd | Professional & scientific | 2016 |
| Gary Food Limited | Wholesale & retail | 2023 |
| Gary Stevens Groundworks Limited | Construction | 2003 |
| GAS and Water Pipelines Limited | Wholesale & retail | 2012 |
| Gascheck Northampton Ltd | Other services | 2017 |
| Gasflow Limited | Energy | 1997 |
| Gasmet Technologies (UK) Limited | Professional & scientific | 1988 |
| Gasp Creative Limited | Information & communication | 2010 |
| Gasworks (Northampton) Limited | Professional & scientific | 2005 |
| GAT Developments (Midlands) Limited | Construction | 2005 |
| Gate House Real Estate Limited | Construction | 2018 |
| Gates Cleaning Services Ltd | Administrative & support | 2024 |
| Gates SET Co Ltd | Information & communication | 2021 |
| Gateway Education UK Limited | Education | 2004 |
| Gateway Holdco Limited | Other services | 2017 |
| Gateway Independent Living Limited | Administrative & support | 2013 |
| Gator Fixings Limited | Wholesale & retail | 2018 |
| Gats Management Limited | Professional & scientific | 2011 |
| Gatti Services Ltd | Information & communication | 2023 |
| Gauges Support Services Ltd | Health & social care | 2021 |
| Gaughan Holdings Limited | Construction | 2022 |
| Gauld Enterprises Ltd | Wholesale & retail | 2018 |
| Gauld Estate Agents Ltd | Real estate | 2024 |
| Gaurdian Health Care Ltd | Health & social care | 2013 |
| Gavel Trans Ltd | Administrative & support | 2016 |
| Gavhad Ltd | Manufacturing | 2023 |
| Gavin Jones Services Ltd | Construction | 2016 |
| Gavin Willis Creative Marketing Limited | Professional & scientific | 2007 |
| Gaywood Developments Limited | Wholesale & retail | 1997 |
| Gaywood Property Management Ltd | Construction | 2020 |
| Gazelle Informatics Limited | Information & communication | 1995 |
| GB Auto Parts Ltd | Wholesale & retail | 2022 |
| GB Builders Progress Ltd | Construction | 2025 |
| GB Contracting UK Limited | Administrative & support | 1998 |
| GB Cranes Limited | Manufacturing | 2024 |
| GB Digital Limited | Professional & scientific | 2022 |
| GB Enforcement Ltd | Administrative & support | 2017 |
| GB EYE Ltd | Wholesale & retail | 1992 |
| GB Hemp Ltd | Wholesale & retail | 2019 |
| GB Interiors Ltd | Construction | 2013 |
| GB Northampton Limited | Hospitality | 2024 |
| GB Reserve Limited | Professional & scientific | 2022 |