| Integrated Paramount Services Limited | Other services | 2012 |
| Integrated Properties Limited | Real estate | 2019 |
| Integrated Property Group Ltd | Real estate | 2026 |
| Integrated Solution Services Ltd | Information & communication | 2023 |
| Integrated Supply Chain Solutions Limited | Transport & logistics | 2024 |
| Integrating Parts Therapy Ltd | Health & social care | 2023 |
| Integritas Labels Limited | Manufacturing | 2024 |
| Integritax Accountants Ltd | Professional & scientific | 2016 |
| Integrity Accountancy Holdings Limited | Real estate | 2017 |
| Integrity Accountancy Limited | Real estate | 2023 |
| Integrity Accountancy Services Limited | Professional & scientific | 2010 |
| Integrity Awards Ltd | Administrative & support | 2023 |
| Integrity Clinical Services Ltd | Professional & scientific | 2007 |
| Integrity Facilities Management Limited | Administrative & support | 2011 |
| Integrity Installations Ltd | Construction | 2019 |
| Integrity Software Systems Limited | Information & communication | 1997 |
| Integrity Trans Link Ltd | Transport & logistics | 2010 |
| Integrity Tuition Limited | Education | 2013 |
| Integro Mortgage Services Limited | Professional & scientific | 2005 |
| Intek Electronics Limited | Information & communication | 1990 |
| Intel Stream Ltd | Information & communication | 2025 |
| Intelexplorations Ltd | Professional & scientific | 2023 |
| Intelisen Limited | Manufacturing | 2019 |
| Inteliwell Limited | Mining & quarrying | 2023 |
| Intellawtual Ltd | Information & communication | 2025 |
| Intellident Ltd | Health & social care | 2025 |
| Intelliga Housing Ltd | Real estate | 2021 |
| Intelligent Accountants Ltd | Professional & scientific | 2024 |
| Intelligent Car Spares Limited | Wholesale & retail | 2011 |
| Intelligent Dental Design Limited | Health & social care | 2011 |
| Intelligent Finance Planning Limited | Financial services | 2001 |
| Intelligent Housing Ltd | Real estate | 2025 |
| Intelligent Risks Limited | Professional & scientific | 2009 |
| Intelligent Services Limited | Manufacturing | 2002 |
| Intelligent Storage Coventry Holdings Limited | Financial services | 2016 |
| Intelligent Storage Coventry Limited | Transport & logistics | 2016 |
| Intelligent Storage Tysley Holdings Limited | Financial services | 2016 |
| Intelligent Storage Tysley Limited | Transport & logistics | 2016 |
| Intelligent Water Services Limited | Professional & scientific | 2011 |
| Intelligentum Limited | Information & communication | 2023 |
| Intelliscale Limited | Information & communication | 2025 |
| Intellismart Limited | Information & communication | 2024 |
| Intellitection Limited | Professional & scientific | 2016 |
| Intellitest Limited | Administrative & support | 2023 |
| Intellitrans Limited | Information & communication | 1996 |
| Intelok Holdings Limited | Administrative & support | 2015 |
| Intelpath UK Limited | Administrative & support | 2024 |
| Intense Green Ltd | Construction | 2017 |
| Intense Ltd | Information & communication | 2023 |
| Intensity Group Services Ltd | Hospitality | 2022 |
| Intensive Works Limited | Information & communication | 2013 |
| Intent Trading Ltd | Professional & scientific | 2022 |
| Intentional Creatives Ltd | Professional & scientific | 2024 |
| Intentional Financial Planning Ltd | Financial services | 2025 |
| Intentional Tenacity Ltd | Professional & scientific | 2024 |
| Intentionsislamicwear Ltd | Wholesale & retail | 2024 |
| Intepro Solutions Limited | Administrative & support | 2010 |
| Inter Bright Futures Ltd. | Hospitality | 2016 |
| Inter City Watch Company Limited | Wholesale & retail | 1993 |
| Inter Petrol LP | | 2011 |
| Inter TEX Link Ltd | Administrative & support | 2011 |
| Inter Trend Ltd | Manufacturing | 2020 |
| Inter-Gems Limited | Extraterritorial | 1977 |
| Interactive Accountants UK Ltd | Professional & scientific | 2017 |
| Interactive Invitations Ltd | Information & communication | 2015 |
| Interactive Projects Limited | Extraterritorial | 2001 |
| Interactive Tutoring Limited | Education | 2025 |
| Interberg Batteries Ltd | Manufacturing | 2025 |
| Interbuy UK Ltd | Wholesale & retail | 2001 |
| Intercar Cleaning (UK) Limited | Wholesale & retail | 2013 |
| Intercar Cleaning Sutton Coldfield Limited | Other services | 2022 |
| Intercept Security Corporation Ltd | Administrative & support | 2010 |
| Interchem (Chemist Wholesale) Limited | Wholesale & retail | 1983 |
| Intercity Ceiling and Partitions Limited | Construction | 2004 |
| Intercity Holdings Overseas Limited | Professional & scientific | 1994 |
| Intercity Managed Services Limited | Information & communication | 2004 |
| Intercity Midlands Limited | Construction | 2011 |
| Intercity Mobile Communications Limited | Professional & scientific | 1989 |
| Intercity Technology Group Holdings Limited | Financial services | 2021 |
| Intercity Technology Group Limited | Administrative & support | 2011 |
| Intercity Technology Holdings Limited | Information & communication | 2015 |
| Intercity Technology Nominee Limited | Financial services | 2017 |
| Intercity Telecom Limited | Professional & scientific | 1989 |
| Intercity Telecommunications Limited | Information & communication | 1997 |
| Interface Administration Services Limited | Professional & scientific | 2010 |
| Interface Estate Planning Ltd | Professional & scientific | 2024 |
| Interface Europe Ltd. | Manufacturing | 1936 |
| Interface Financial Planning Limited | Financial services | 1991 |
| Interface UK Manufacturing Limited | Manufacturing | 2010 |
| Interfruit Catering Limited | Manufacturing | 1995 |
| Interhygiene Ltd | Professional & scientific | 2021 |
| Interia Group Limited | Professional & scientific | 2017 |
| Interim Operations Support Limited | Professional & scientific | 2024 |
| Interior Artists Limited | Professional & scientific | 1999 |
| Interior Ceilings and Partitions Ltd | Construction | 2016 |
| Interiors by Sutton Ltd | Wholesale & retail | 2022 |
| Interiors by T'Mara Ltd | Professional & scientific | 2025 |
| Interliked Ltd | Professional & scientific | 2022 |
| Interlink Exhibitions Limited | Extraterritorial | 2003 |
| Interlink Graphics Limited | Extraterritorial | 1994 |