| Icon (Environmental) Consulting Ltd | Professional & scientific | 2007 |
| Igloo Furniture Limited | Manufacturing | 2009 |
| Ignite Chiropractic Limited | Health & social care | 2019 |
| Images of Wild Nature Ltd | Administrative & support | 2009 |
| Imaginative Projects Limited | Construction | 2018 |
| Imaginative Trading Limited | Wholesale & retail | 2018 |
| Impeccable Edge Sharpening Ltd | Manufacturing | 2025 |
| Imperus Services Limited | Real estate | 2020 |
| IN Demand Items Ltd | Wholesale & retail | 2022 |
| Independant Catering Limited | Hospitality | 2019 |
| Independent Company Ventures Limited | Financial services | 2024 |
| Independent Expert Engineer Ltd | Professional & scientific | 2024 |
| Independent Renewables Company Limited | Construction | 2025 |
| Independent Testing Company Limited | Construction | 2012 |
| Independent Testing Property Holdings Limited | Real estate | 2022 |
| Industrial Water Equipment Limited | Water & waste | 2007 |
| Infography Ltd. | Information & communication | 2010 |
| Infrawave Limited | Construction | 2025 |
| Ingenius Buildings Limited | Professional & scientific | 2007 |
| Inner Golf Limited | Financial services | 2021 |
| Inner Wellbeing Ltd | Education | 2021 |
| Inside the Box Board Games LLP | | 2015 |
| Inside the Box Game Studio Ltd | Manufacturing | 2020 |
| Inspector Play Ltd | Education | 2022 |
| Inspired Hire Limited | Administrative & support | 2022 |
| Institute of Quarrying(The) | Other services | 1958 |
| Instrumentation (UK) Ltd | Professional & scientific | 2010 |
| Intacare Limited | Health & social care | 1990 |
| Intacare Residential Ltd | Health & social care | 2026 |
| Integrated Contamination Management UK Ltd | Professional & scientific | 1994 |
| Intelligence Bureau Limited | Other services | 2019 |
| Interchange People Development Ltd | Education | 2013 |
| Interstellar Audio Ltd | Information & communication | 2022 |
| Into the Great Wide Open Limited | Agriculture & fishing | 2022 |
| IOW Holdings Limited | Real estate | 2020 |
| Irony Fireside Limited | Administrative & support | 2015 |
| Itcouldbecheaper Ltd | Administrative & support | 2013 |
| J & E Uphill Commercial Properties Limited | Real estate | 2024 |
| J & E Uphill Holdings Limited | Financial services | 2024 |
| J & E Uphill Investments Limited | Real estate | 2026 |
| J a Barker Limited | Transport & logistics | 2001 |
| J and N Properties(Matlock) Limited | Households | 2021 |
| J Ashby Tree Services Ltd | Agriculture & fishing | 2018 |
| J B Property Derbyshire Ltd | Real estate | 2024 |
| J Barlow & Family Funeral Services Limited | Other services | 2026 |
| J Coles Plumbing & Heating Limited | Construction | 2011 |
| J E Furness Limited | Financial services | 2017 |
| J G Cattle Services Limited | Agriculture & fishing | 2015 |
| J J G Training Limited | Professional & scientific | 2006 |
| J Kiely Ltd | Hospitality | 2019 |
| J. C. Else Limited | Agriculture & fishing | 2015 |
| J.B.L.H Building Ltd | Construction | 2024 |
| J.J.Furness Limited | Agriculture & fishing | 1949 |
| J.W. and J. Mettam (1981) Limited | Other services | 1982 |
| Jackson Homes Ltd | Real estate | 2026 |
| Jackson Property Solutions Ltd | Real estate | 2015 |
| Jaleve Limited | Hospitality | 2018 |
| Jama Plastering Ltd | Construction | 2012 |
| James Boon Architects Ltd | Professional & scientific | 2018 |
| Jameson Healthcare & Mobility Limited | Wholesale & retail | 2001 |
| JBA Photography & Training Limited | Information & communication | 2003 |
| JCG Matlock Limited | Real estate | 2025 |
| JD Networking Limited | Administrative & support | 2018 |
| Jeffery Martin Holdings Ltd | Financial services | 2019 |
| Jeffery Martin Properties Ltd | Real estate | 2017 |
| Jemcolin Consulting Limited | Water & waste | 2006 |
| Jepson Funerals Limited | Other services | 1960 |
| Jeremy J. Fearn Motor Engineers Limited | Manufacturing | 2002 |
| JH Fencing and Environmental Limited | Administrative & support | 2019 |
| JHF Transport Services Limited | Professional & scientific | 2014 |
| JJG Consultants Limited | Professional & scientific | 2011 |
| JJM Network Consultancy Ltd | Construction | 2004 |
| JK Recycling Services Limited | Water & waste | 2017 |
| JL & M Limited | Professional & scientific | 2006 |
| Jlb-It Services Limited | Information & communication | 2001 |
| JMH Haulage Limited | Transport & logistics | 2024 |
| JMI Holdings Ltd | Real estate | 2017 |
| JMI Parris Properties Ltd | Real estate | 2017 |
| JMS Haulage Limited | Water & waste | 2015 |
| JMS Heating Ltd | Construction | 2019 |
| John Palin Fresh Produce Ltd | Manufacturing | 2003 |
| John Smedley Archive Charitable Trust | Arts & recreation | 2016 |
| John Smedley Limited | Manufacturing | 1893 |
| John Watkinson & Associates Limited | Administrative & support | 2018 |
| Jonas and Jonas Ltd | Health & social care | 2026 |
| Jones & Bone Limited | Administrative & support | 2015 |
| Josef Dylan Imports Ltd | Wholesale & retail | 2016 |
| Joseph Clayton & Sons Ltd | Construction | 2023 |
| JR Craft Fairs Ltd | Administrative & support | 2021 |
| JTW Estates Ltd | Households | 2020 |
| Jukes Productions Limited | Arts & recreation | 1980 |
| Julie Anne Hart.Com Ltd | Other services | 2016 |
| Julius Catering Ltd | Hospitality | 2019 |
| Jumero Software Services Ltd | Extraterritorial | 2021 |
| Just 3 Architectural Aluminium Ltd | Construction | 2019 |
| Just Identification Systems Ltd | Administrative & support | 2015 |
| Justagin Limited | Hospitality | 2014 |
| JW Development Ltd | Information & communication | 2009 |
| JW Home Surveys Ltd | Other services | 2024 |
| JWT Plumbing and Heating Limited | Construction | 2016 |