| Industria Solar Fallaws Limited | Energy | 2021 |
| Industria Solar Financials Limited | Energy | 2021 |
| Industria Solar Forfar Limited | Energy | 2021 |
| Industria Solar Limited | Energy | 2021 |
| Industria Solar Vigo Limited | Energy | 2021 |
| Infinity 8 Logistics Ltd | Wholesale & retail | 2018 |
| Infinity Practice Limited | Extraterritorial | 2015 |
| Inflection Consulting Ltd | Professional & scientific | 2025 |
| Ingeneious Threads Ltd | Manufacturing | 2025 |
| Inkay P Ltd | Real estate | 2025 |
| Inmo Solutions Ltd | Information & communication | 2023 |
| Innovation Catalyst Ltd | Professional & scientific | 2024 |
| Insider Travel Group Ltd | Administrative & support | 2023 |
| Instaclean Solutions Limited | Administrative & support | 2024 |
| Instaseal Limited | Construction | 2016 |
| Instaseal Sub-Structure Protection Ltd | Construction | 2022 |
| Institute for Business Development in Euro Asia Limited | Education | 1993 |
| Instyle Beds Limited | Wholesale & retail | 2008 |
| Integrated Fire Systems Ltd | Manufacturing | 2013 |
| Integrated Roofing Systems (NE) Limited | Construction | 2019 |
| International Planning Services Limited | Construction | 2025 |
| International Porters Limited | Transport & logistics | 2026 |
| Inwebro Services Limited | Information & communication | 2025 |
| IPM Productions Limited | Information & communication | 2023 |
| IQ Legal Training Ltd | Other services | 2019 |
| Istanbul Haircut Ltd | Other services | 2022 |
| Istanbul Meats Limited | Manufacturing | 2001 |
| ITM Electrical Services Ltd | Other services | 2018 |
| Itps (Holdings) Limited | Professional & scientific | 2006 |
| Itps Bidco Limited | Information & communication | 2020 |
| Itps Colocation Limited | Information & communication | 2022 |
| Itps Midco Limited | Extraterritorial | 2020 |
| Itps Topco Limited | Professional & scientific | 2020 |
| Iyabo Ltd | Financial services | 2025 |
| J and J Construction Group Ltd | Construction | 2025 |
| J D European Horses Limited | Agriculture & fishing | 2008 |
| J G Turnbull Limited | Manufacturing | 1989 |
| J Maddison Rental Ltd | Real estate | 2024 |
| J&K Utilities Limited | Construction | 2024 |
| J&L Real Estate Ltd | Extraterritorial | 2013 |
| J. Dinning (Investments) Limited | Professional & scientific | 2012 |
| J.E.M Road Construction Ltd | Transport & logistics | 2005 |
| J.S.H. Collectables Limited | Wholesale & retail | 2026 |
| J.W.T Construction & Maintenance N/E Ltd | Construction | 2023 |
| J04 Traders Ltd | Real estate | 2022 |
| Jackson Accountancy Services Limited | Professional & scientific | 2018 |
| JAG Hook Limited | Administrative & support | 2015 |
| Jajp Ltd | Hospitality | 2025 |
| JAK HQ Limited | Professional & scientific | 2016 |
| Jalew Enterprises Limited | Wholesale & retail | 2019 |
| JAM Yule Contracts Ltd | Construction | 2014 |
| James the Green MAN Limited | Other services | 2010 |
| Jane Rose Holdings Limited | Financial services | 2021 |
| Janney's Holdings Ltd | Real estate | 2025 |
| Jarola Group Limited | Real estate | 2024 |
| Jasmine Patisserie Ltd | Manufacturing | 2023 |
| JAY Carter Aesthetics Limited | Other services | 2022 |
| JAZ Training Limited | Other services | 2012 |
| JB Property Portfolio Ltd | Real estate | 2025 |
| JCC Welding Ltd | Manufacturing | 2018 |
| JD Fish@ Grill Ltd | Hospitality | 2025 |
| JD Holdings Limited | Construction | 2025 |
| JE Hughes Limited | Real estate | 2026 |
| Jeff Johnston Limited | Information & communication | 2023 |
| Jenny Wren Paintings Limited | Arts & recreation | 2021 |
| Jensrewear Ltd | Wholesale & retail | 2026 |
| Jesalant Limited | Professional & scientific | 2016 |
| Jewel Line Ltd | Hospitality | 2024 |
| JFS HR Limited | Real estate | 2011 |
| JH Partners - MEP Design & Digital Engineering Limited | Administrative & support | 2024 |
| JH Rope Access Ltd | Construction | 2025 |
| JHB CAD Technician Limited | Manufacturing | 2023 |
| Jinco Limited | Hospitality | 2014 |
| Jinit M Patel Ltd | Hospitality | 2025 |
| Jit-Gurus Ltd | Wholesale & retail | 2026 |
| JK Properties (North East) Ltd | Real estate | 2017 |
| JKF Contractors (North East) Limited | Construction | 2012 |
| JLI Consultancy Ltd | Health & social care | 2025 |
| JMB Music Group Ltd | Professional & scientific | 2021 |
| JMC Plumbing & Heating Ltd | Administrative & support | 2015 |
| JN GAS Utilities Limited | Construction | 2025 |
| Job.Zip Ltd | Information & communication | 2023 |
| Jock Fraser (Scotland) Limited | Professional & scientific | 1982 |
| Joelco Limited | Information & communication | 2014 |
| John Hamilton Diagnostics Ltd | Wholesale & retail | 2026 |
| John Jackson 4 Compliance Ltd | Professional & scientific | 2022 |
| John Maclaren & Sons (Scotland) Limited | Wholesale & retail | 1982 |
| Johnnys Fish Bar Ltd | Hospitality | 2026 |
| Johnson Property Letting Limited | Real estate | 2021 |
| Jolly Giant Toy Superstore Limited | Wholesale & retail | 2025 |
| Jolly Giant Toystores Limited | Wholesale & retail | 2025 |
| Jonny Turnbull Limited | Information & communication | 2014 |
| Jordan UK Investments Limited | Financial services | 2022 |
| Jordon Fitness Ltd. | Other services | 2017 |
| Jp&T Adventures Ltd | Hospitality | 2026 |
| JPC Ecology Ltd | Professional & scientific | 2012 |
| JPH Legal Services Ltd | Professional & scientific | 2017 |
| JPJ Positive Change CIC | Other services | 2004 |
| JPS Build Centre Ltd | Wholesale & retail | 2020 |
| Jr@Jj Joinery Limited | Construction | 2024 |