| Indiefrog Limited | Information & communication | 2017 |
| Infinity Algorithms Ltd | Wholesale & retail | 2026 |
| Infinity Edge Services Limited | Administrative & support | 2024 |
| Infinity Gaming Services Limited | Information & communication | 2026 |
| Ingem Construct Ltd | Construction | 2024 |
| Inkacreations Ltd | Manufacturing | 2025 |
| Inkspired Studio Ltd | Professional & scientific | 2025 |
| Inkt Ltd | Professional & scientific | 2009 |
| Inline Security Ltd | Administrative & support | 2025 |
| Insane Gentlemen Ltd | Wholesale & retail | 2013 |
| Inspire Equip Change Ltd | Education | 2025 |
| Inspire Sports UK Ltd | Arts & recreation | 2025 |
| Inspiring Your Future Ltd | Professional & scientific | 2024 |
| Integral Security Protection Ltd | Administrative & support | 2023 |
| INTEGRAL2025 CIC | Professional & scientific | 2025 |
| Integrity - Bifold Door Repairs Limited | Construction | 2018 |
| Inten Brand Design Ltd | Professional & scientific | 2025 |
| International Blade Repair Ltd | Manufacturing | 2026 |
| Interview IQ Limited | Education | 2025 |
| Intra Home Care Agency Ltd | Health & social care | 2023 |
| Invest First Limited | Real estate | 2006 |
| Invisatex Ltd | Financial services | 2026 |
| Invision Capital Ltd | Wholesale & retail | 2020 |
| Ionut CZ Limited | Construction | 2020 |
| Ipecc Solutions Limited | Information & communication | 2014 |
| Iphy Healthcare Ltd | Health & social care | 2020 |
| IR Security Systems Limited | Information & communication | 2019 |
| ISHINE2005 Ltd | Administrative & support | 2023 |
| Islamabad Halal Butchers Ltd | Wholesale & retail | 2012 |
| Israrlatif Ltd | Wholesale & retail | 2024 |
| Istasha Ltd | Wholesale & retail | 2025 |
| IT Expert International Ltd | Information & communication | 2014 |
| Ithink Innovations Ltd | Professional & scientific | 2015 |
| Itile London Ltd | Construction | 2025 |
| Itruck Expedition Limited | Transport & logistics | 2023 |
| Ivascu Services Solutions Limited | Construction | 2024 |
| Iwon Ltd | Financial services | 2025 |
| J and S Playhouse Limited | Health & social care | 2018 |
| J Fresh Mart Ltd | Wholesale & retail | 2025 |
| J P Crowe Groundworks Limited | Construction | 2015 |
| J R Robinson Teaching Ltd | Administrative & support | 2016 |
| J. Marclan Ltd | Professional & scientific | 2020 |
| J. W. Stephen Ltd. | Professional & scientific | 2016 |
| Jack of ALL Solutions Ltd | Water & waste | 2026 |
| Jack VS. AI Ltd | Information & communication | 2025 |
| Jacob & Co Opticians Ltd | Wholesale & retail | 2025 |
| Jacobs Aleitr Ltd | Wholesale & retail | 2023 |
| Jadiah Int'L Grocery Store Ltd | Wholesale & retail | 2024 |
| Jagdish Chandra Ltd | Wholesale & retail | 2022 |
| Jahangir Tanoli Ltd | Wholesale & retail | 2025 |
| Jalals Butchers & Grocers Limited | Wholesale & retail | 2019 |
| Jaluice UK Limited | Wholesale & retail | 2025 |
| Jamal Furniture House Ltd | Wholesale & retail | 2014 |
| Jamil Traders Ltd | Wholesale & retail | 2014 |
| Jarral Chauffeur Services PVT Ltd | Wholesale & retail | 2026 |
| Jarvis Store Ltd | Wholesale & retail | 2025 |
| Jatt Transport Services Ltd | Transport & logistics | 2021 |
| Jatto Travel Ltd | Professional & scientific | 2023 |
| JAY Monique Limited | Other services | 2017 |
| Jayeeth Property Services Ltd | Real estate | 2025 |
| Jaymike GH Ltd | Construction | 2025 |
| Jaynivash Limited | Wholesale & retail | 2025 |
| Jaynvik Limited | Wholesale & retail | 2024 |
| Jayrob Services Ltd | Transport & logistics | 2019 |
| JB Prop Services Ltd | Real estate | 2024 |
| JBE Management Services Ltd | Real estate | 2014 |
| JBM FAN Ltd | Health & social care | 2021 |
| JBM Care Services Ltd | Health & social care | 2024 |
| JBM P Touch Ltd | Wholesale & retail | 2021 |
| JBS Star Limited | Administrative & support | 2016 |
| JCA Hair Ltd | Wholesale & retail | 2023 |
| JDA Construction Ltd | Construction | 2022 |
| Jeanette Young Limited | Manufacturing | 2013 |
| Jemi Builders Limited | Construction | 2025 |
| Jemtaliving Ltd | Health & social care | 2025 |
| Jenc Assets Ltd | Real estate | 2026 |
| Jenc Ltd | Health & social care | 2014 |
| Jennifer Paris Limited | Health & social care | 2024 |
| Jerk Chicken Cuisine Ltd | Hospitality | 2017 |
| Jerry's Sushi Ltd | Hospitality | 2024 |
| Jett Customs Limited | Wholesale & retail | 2021 |
| Jeya Enterprises Ltd | Wholesale & retail | 2015 |
| Jimenez Services Ltd | Wholesale & retail | 2025 |
| JJ Global Ventures Ltd | Wholesale & retail | 2025 |
| JJ Meat and Grocers Limited | Wholesale & retail | 2024 |
| JKC Carpentry Limited | Construction | 2020 |
| Jkevent Decoration Ltd | Hospitality | 2024 |
| JKG Property Investments Ltd | Real estate | 2018 |
| JL Heat & Plumbing Ltd | Construction | 2019 |
| Jlls Fast Food Ltd | Hospitality | 2023 |
| JM Fire Safety Services Ltd | Public administration | 2024 |
| JMG GAS Services Limited | Professional & scientific | 2018 |
| JN Global Supplies Ltd | Wholesale & retail | 2025 |
| Joachinmac Ltd | Construction | 2018 |
| Jomo Domestic Cleaning Ltd | Administrative & support | 2023 |
| Joopio Ltd | Professional & scientific | 2016 |
| Joseph & Co Heating Limited | Construction | 2017 |
| Jotunheim Group Ltd | Hospitality | 2023 |
| JPM MAX Limited | Construction | 2013 |
| JR & Partners Limited | Wholesale & retail | 2022 |