| Innocryst Ltd | Professional & scientific | 2013 |
| Innolas (UK) Limited | Manufacturing | 1997 |
| Innomirai Technologies Ltd | Administrative & support | 2026 |
| Innoscope Limited | Professional & scientific | 2009 |
| Innospark Technologies Ltd | Information & communication | 2024 |
| Innosphere Technologies Limited | Wholesale & retail | 2025 |
| Innova Joinery & Construction Ltd | Manufacturing | 2025 |
| Innovacode Technologies Ltd | Information & communication | 2025 |
| Innovai Consulting Ltd | Professional & scientific | 2025 |
| Innovatable Ltd | Administrative & support | 2023 |
| Innovate Aluminium Systems Limited | Manufacturing | 2021 |
| Innovate OPS Consultancy Ltd | Professional & scientific | 2024 |
| Innovate to Create Limited | Health & social care | 2016 |
| Innovation & Intelligence Ltd | Information & communication | 2017 |
| Innovation Aluminium Limited | Manufacturing | 2022 |
| Innovation in Point of Sale Ltd | Manufacturing | 2017 |
| Innovations NS Limited | Information & communication | 2022 |
| Innovative Clothing Limited | Manufacturing | 2000 |
| Innovative Educational Partnerships Limited | Education | 2023 |
| Innovative Food Brands Ltd | Hospitality | 2020 |
| Innovative Gates and Fencing Ltd | Manufacturing | 2024 |
| Innovative Holdings Limited | Financial services | 2018 |
| Innovative Investments Ltd | Administrative & support | 2004 |
| Innovative Leisure (Operations) Ltd | Arts & recreation | 2003 |
| Innovative Leisure Limited | Arts & recreation | 2000 |
| Innovative Rentals Ltd | Real estate | 2025 |
| Innovest Consulting Ltd | Real estate | 2025 |
| Innovologies Ltd | Professional & scientific | 2023 |
| Innowise Solutions Limited | Information & communication | 2012 |
| Inovantage Ltd | Other services | 2022 |
| Inovatech Global Limited | Wholesale & retail | 2017 |
| Inox Research Ltd | Other services | 2012 |
| Inpro Export Services Limited | Professional & scientific | 2006 |
| Inproduction Ltd | Information & communication | 2005 |
| Input Consulting Limited | Professional & scientific | 2022 |
| INR Media House Limited | Real estate | 2025 |
| Insa Investments Limited | Real estate | 2025 |
| Insecta Collective CIC | Arts & recreation | 2023 |
| Inside Edge Limited | Arts & recreation | 1996 |
| Inside OUT Domestics Limited | Administrative & support | 2002 |
| Insideoutbeautyuk Ltd | Wholesale & retail | 2024 |
| Insight App Limited | Information & communication | 2021 |
| Insight Displays UK Ltd | Manufacturing | 2026 |
| Insight Financial Analytics Ltd | Professional & scientific | 2025 |
| Insight Property Management Limited | Real estate | 2018 |
| Insighted Strategies Ltd | Information & communication | 2024 |
| Insightprime Consulting Limited | Information & communication | 2025 |
| Insist Construction Ltd | Construction | 2018 |
| Insita Limited | Professional & scientific | 2023 |
| Insitu Display Limited | Transport & logistics | 2002 |
| Insmart Limited | Professional & scientific | 2004 |
| Insollz Ltd | Manufacturing | 2021 |
| Insono AV Ltd | Construction | 2026 |
| Insouciance Ltd | Wholesale & retail | 2021 |
| Inspect Property Ltd | Professional & scientific | 2008 |
| Inspection View Ltd | Information & communication | 2022 |
| Inspectivo Ltd | Information & communication | 2025 |
| Inspirate | Arts & recreation | 2012 |
| Inspirational Arts Performance CIC | Arts & recreation | 2026 |
| Inspirational Labels Ltd | Manufacturing | 2023 |
| Inspirational Wellbeing Ltd | Wholesale & retail | 2024 |
| Inspirations Flex Ltd | Real estate | 2025 |
| Inspirations Hair and Beauty Fleckney Limited | Other services | 2012 |
| Inspirations Holdings Ltd | Real estate | 2021 |
| Inspirations Housing Ltd | Real estate | 2024 |
| Inspirations Leicestershire Limited | Health & social care | 2011 |
| Inspirations Property Ltd | Real estate | 2026 |
| Inspire Care Homes Ltd | Health & social care | 2026 |
| Inspire Crafts Online Ltd | Wholesale & retail | 2023 |
| Inspire Facilities Management Limited | Professional & scientific | 2022 |
| Inspire Learning Services Ltd | Education | 2024 |
| Inspire Leicester Limited | Education | 2021 |
| Inspire Lives Care Services Ltd | Hospitality | 2022 |
| Inspire Security Solutions Ltd | Construction | 2022 |
| Inspire Sports Academy Limited | Arts & recreation | 2018 |
| Inspire Together Leicester CIC | Education | 2023 |
| Inspirecraft Global Ltd | Professional & scientific | 2025 |
| Inspired Bespoke Interiors Limited | Manufacturing | 2013 |
| Inspired Care 4ALL Ltd | Health & social care | 2022 |
| Inspired Living Limited | Health & social care | 2023 |
| Inspired POS Limited | Wholesale & retail | 2022 |
| Inspired Print Solutions Limited | Manufacturing | 2020 |
| Inspiregen CIC | Education | 2025 |
| Inspiring Happiness CIC | Administrative & support | 2024 |
| Inspiring YOU C.I.C. | Education | 2016 |
| Install U.K. Midland Ltd | Construction | 2018 |
| Installation Services (Leicester) Limited | Construction | 2003 |
| Instalyf Holdings Ltd | Financial services | 2026 |
| Instalyf Investments Ltd | Financial services | 2026 |
| Instalyf Ventures Ltd | Financial services | 2026 |
| Instant Cleaners Ltd | Administrative & support | 2025 |
| Instant Cleaning Services UK Ltd | Administrative & support | 2021 |
| Instant Inventory Limited | Professional & scientific | 2025 |
| Instant Pack Limited | Administrative & support | 2022 |
| Instant Tech Limited | Information & communication | 2025 |
| Instant Tyre Fit Ltd | Manufacturing | 2025 |
| Instigate Productions Ltd | Information & communication | 2024 |
| Instinct Design UK Ltd | Manufacturing | 2014 |
| Instore Limited | Professional & scientific | 1938 |
| Instructa App Limited | Information & communication | 2025 |