| Garden View RTM Company Limited | Hospitality | 2012 |
| Gardiner Graphics Group Limited | Manufacturing | 1995 |
| Garity Brickwork Ltd | Construction | 2014 |
| Garl Winchester Limited | Wholesale & retail | 2021 |
| Garnead Limited | Construction | 1992 |
| Garnead Plant Limited | Construction | 2026 |
| Garner Wood Limited | Real estate | 1995 |
| Gary Lovejoy GAS & Heating Services Ltd | Construction | 2023 |
| GAS & Electrical Training Ltd | Education | 2015 |
| GAS Distribution Services Ltd | Administrative & support | 2010 |
| Gas-Flow Solutions Ltd | Construction | 2024 |
| Gascore Ltd | Construction | 2023 |
| Gastech Heating South Ltd | Construction | 2026 |
| Gastrovision Limited | Health & social care | 2019 |
| Gatcombe Industrial Limited | Construction | 2021 |
| Gates Brothers Damp Proofing Ltd | Other services | 2019 |
| Gatford Plumbing Ltd | Energy | 2018 |
| Gavin Bleach Brickwork Limited | Construction | 2019 |
| Gavin Driver Plumbing & Heating Ltd | Construction | 2015 |
| GB Assets Ltd | Real estate | 2015 |
| GB Film & TV Catering Ltd | Hospitality | 2024 |
| GB Mobility Consultants Ltd | Professional & scientific | 2018 |
| GB ROW Challenge Ltd | Arts & recreation | 2012 |
| GB. Gourmet Foods Limited | Hospitality | 2007 |
| Gbnf T/A AO Trading Ltd | Information & communication | 2025 |
| GBP Safety Training & Consultancy Ltd | Public administration | 2014 |
| GC Bike Repairs Ltd | Manufacturing | 2022 |
| GC Southern Limited | Construction | 2022 |
| Gcsk Limited | Construction | 2012 |
| GDG Consultants Ltd | Professional & scientific | 2013 |
| GDH Solutions UK Limited | Information & communication | 2010 |
| GDO Building Services Ltd | Professional & scientific | 2026 |
| Gdpr-Info Limited | Information & communication | 2016 |
| GDR Recycling Limited | Administrative & support | 2019 |
| GDT Wealth Management Limited | Financial services | 2014 |
| Gebr. Noort Limited | Wholesale & retail | 2020 |
| Gelateria Danieli Limited | Manufacturing | 2004 |
| Gelderson Consultants Limited | Information & communication | 2013 |
| GEM Air Conditioning Limited | Energy | 2019 |
| Gemini Home & Ground Care Services Ltd | Construction | 2024 |
| GEN Z Autos Ltd | Wholesale & retail | 2025 |
| Gen-Rg UK Limited | Wholesale & retail | 2022 |
| Genecheck Ltd | Professional & scientific | 2022 |
| General Store Winchester Limited | Wholesale & retail | 2020 |
| Generation Building Projects Ltd | Construction | 2023 |
| Genius Capital Limited | Information & communication | 2019 |
| Genius Construction Solutions Ltd | Extraterritorial | 2002 |
| Genius Contracts Limited | Construction | 2017 |
| Genius Money Limited | Professional & scientific | 2017 |
| Genius Payroll Limited | Construction | 2010 |
| Genius Work Force Solutions Ltd | Extraterritorial | 2000 |
| Genoa Residential Limited | Real estate | 2015 |
| Gentec Services Ltd | Manufacturing | 2007 |
| GEO M&E Ltd | Construction | 2020 |
| Geo,A.Dick Limited | Construction | 1961 |
| GEO. a Smith Building Services Ltd | Construction | 2025 |
| Geoff Banks Limited | Information & communication | 2006 |
| Geopolitical Solutions Ltd | Other services | 2001 |
| George Developments Limited | Construction | 2023 |
| Georgina Court Southsea Freehold Limited | Households | 2018 |
| Geqs Limited | Professional & scientific | 2020 |
| Gerald Reyes Works Limited | Health & social care | 2025 |
| Gerard's Quality Solutions Ltd | Professional & scientific | 2020 |
| Gerrell & Hard Limited | Administrative & support | 2011 |
| GET Busi Ltd | Administrative & support | 2025 |
| GET GAS Safe Ltd | Education | 2023 |
| GET UP & Grow Limited | Administrative & support | 2017 |
| Geteck Group Limited | Professional & scientific | 2015 |
| Gethin Jones Unlocking Potential Limited | Professional & scientific | 2018 |
| GG Solar Ltd | Construction | 2025 |
| GG-393-515 Limited | Real estate | 2022 |
| Ghosh Spice Limited | Hospitality | 2024 |
| Ghost Dog Pets Ltd | Manufacturing | 2024 |
| GHS 13 Ltd | Transport & logistics | 2019 |
| GHT Couriers Ltd | Transport & logistics | 2023 |
| GI Asset Management Limited | Real estate | 2003 |
| Giaccs Limited | Financial services | 2018 |
| Gibo Demo Limited | Construction | 2020 |
| Gileco Design Ltd | Professional & scientific | 2025 |
| Giles Eccleston Ltd | Construction | 2012 |
| Giles GAS & Plumbing Ltd | Construction | 2023 |
| Gilesnet Ltd | Households | 2016 |
| Ginger Labs Limited | Information & communication | 2010 |
| Ginkgo Southsea LLP | | 2019 |
| Giorgio's Restaurants Limited | Hospitality | 2016 |
| Giraffe Marketing Group Limited | Professional & scientific | 2012 |
| Giraffe Social Media Limited | Professional & scientific | 2012 |
| Girlz Beautique Ltd | Other services | 2022 |
| Given Developments Limited | Construction | 2024 |
| Gixer Electrical Limited | Construction | 2016 |
| GK Scott Holdings Limited | Financial services | 2019 |
| GKM Accountants Limited | Professional & scientific | 2013 |
| GL Capital Partners Ltd | Real estate | 2017 |
| GL Plastering and Refurbishment Limited | Construction | 2017 |
| Gladysmaint Ltd | Real estate | 2025 |
| Glam Afrique Limited | Wholesale & retail | 2025 |
| Glamour Getaways Ltd | Real estate | 2026 |
| Glass Properties (Southern) Limited | Construction | 2022 |
| Glaze-Tec (UK) Limited | Construction | 2003 |
| GLD Couriers Ltd | Transport & logistics | 2025 |