| IN Essence XN Ltd | Wholesale & retail | 2025 |
| IN Motion London Ltd | Wholesale & retail | 2026 |
| Inakhi Limited | Wholesale & retail | 2021 |
| Inclusive Immersion Limited | Information & communication | 2022 |
| Increase IT Ltd | Construction | 2019 |
| IND Ocean Limited | Administrative & support | 2021 |
| Indbar Ltd | Hospitality | 2025 |
| Independence Fulfillment Services Ltd | Wholesale & retail | 2022 |
| Indes Bar Limited | Hospitality | 2014 |
| Indian Fusion Catering Ltd | Hospitality | 2025 |
| Indian Ocean Flavours Limited | Hospitality | 2016 |
| Indigo Food Service Ltd | Hospitality | 2018 |
| Indore Sizzlers UK Limited | Hospitality | 2026 |
| Indus International Limited | Wholesale & retail | 2015 |
| Induspot Ltd | Wholesale & retail | 2023 |
| Industrial Hygiene (UK) Ltd | Wholesale & retail | 2011 |
| Industrial Pipework (London) Limited | | 1965 |
| Inee Limited | Information & communication | 2013 |
| Infa.Avail Ltd | Wholesale & retail | 2021 |
| Inferno LUX Ltd | Professional & scientific | 2025 |
| INFIN8 Brands UK EU Ltd | Wholesale & retail | 2020 |
| Infinitai Tech Ltd | Information & communication | 2025 |
| Infinite Concept Limited | Professional & scientific | 2008 |
| Infinite Consulting Ltd | Professional & scientific | 2022 |
| Infinite Finance London Limited | Financial services | 2023 |
| Infinite Solutions Consultancy Limited | Professional & scientific | 2023 |
| Infinity Electric Bike Ltd | Wholesale & retail | 2023 |
| Infinity Energy Organisation Limited | Administrative & support | 2012 |
| Infinity Finance UK Services Ltd | Administrative & support | 2024 |
| Infinity Luxury Homes Limited | Construction | 2025 |
| Infinity Manpower Group Ltd | Administrative & support | 2022 |
| Infinity Medics Ltd. | Health & social care | 2022 |
| Infinity Portable Power Stations Ltd | Wholesale & retail | 2023 |
| Infinity Property Management Limited | Construction | 2010 |
| Infinity Solar UK Limited | Energy | 2015 |
| Infinity Strategic Solutions Limited | Wholesale & retail | 2020 |
| Infinity UK Cars Ltd | Wholesale & retail | 2018 |
| Infinivit Ltd | Wholesale & retail | 2022 |
| Influenced Marketing Ltd | Professional & scientific | 2023 |
| Info Cube Consultants (Europe) Limited | Information & communication | 2007 |
| Infoba Ltd | Information & communication | 2019 |
| Infogrid Solutions Limited | Wholesale & retail | 2013 |
| Inforian Electronics Ltd | Wholesale & retail | 2025 |
| Infosecmsp Ltd | Information & communication | 2024 |
| Infotech Software Limited Limited | Information & communication | 2025 |
| Infradecision Ltd | Wholesale & retail | 2014 |
| Infrastru Consulting Ltd | Construction | 2021 |
| Infrastru Limited | Professional & scientific | 2016 |
| Infycup Limited | Manufacturing | 2025 |
| Inga Homes Limited | Extraterritorial | 2018 |
| Ingeniouscrew Ltd | Hospitality | 2024 |
| Inhand Solutions Limited | Professional & scientific | 2022 |
| Initial Development Services Limited | Administrative & support | 2018 |
| INK and Cauldron Limited | Information & communication | 2016 |
| INK Arabic Ltd | Wholesale & retail | 2025 |
| Inked Revolution Media Ltd | Information & communication | 2023 |
| Inklite Ltd | Wholesale & retail | 2024 |
| Inkspread Limited | Wholesale & retail | 2025 |
| Inner Instincts Ltd | Professional & scientific | 2021 |
| Inner Strength Project CIC | Education | 2026 |
| Inner ZEN Candles Ltd | Arts & recreation | 2024 |
| Innernote AI Co. Ltd | Health & social care | 2020 |
| Innoquest UK Ltd | Wholesale & retail | 2025 |
| Innor Travel Ltd | Administrative & support | 2026 |
| Innora Consulting Limited | Other services | 2025 |
| Innova Solutions Group Ltd | Construction | 2023 |
| Innovate ESG Ltd | Information & communication | 2006 |
| Innovate Software Consulting Inc Ltd. | Information & communication | 2013 |
| Innovation Builders Ltd | Construction | 2017 |
| Innovation Hub International Ltd | Real estate | 2020 |
| Innovative Capital Partners Limited | Professional & scientific | 2010 |
| Innovator Publishing & Editorial Services Ltd | Administrative & support | 2018 |
| Inoxe Ltd | Wholesale & retail | 2022 |
| INP Health Services Ltd | Health & social care | 2026 |
| Inproject Construction Ltd | Construction | 2023 |
| Inseal Ltd | Other services | 2015 |
| Insein | Education | 2011 |
| Inshallah Halal Meat Limited | Wholesale & retail | 2017 |
| Inside Edit Ltd | Hospitality | 2025 |
| Inside Maintenance Limited | Construction | 2023 |
| Inside OUT Aesthetics and Wellness Ltd | Other services | 2021 |
| Insightedge Behavioural Consultancy Ltd | Professional & scientific | 2026 |
| Inspire 360 Property Solutions Ltd | Other services | 2019 |
| Inspire and Create Limited | Public administration | 2021 |
| Inspire College of Technologies UK Ltd | Education | 2022 |
| Inspired Indian Limited | Hospitality | 2016 |
| Inspired Pharmacare Ltd | Health & social care | 2024 |
| Insta RO Limited | Construction | 2018 |
| Installation Mechanical Services Ltd | Construction | 2026 |
| Instant Video (UK) Limited | Other services | 1992 |
| Institute of Islamic Banking and Insurance | Other services | 1994 |
| Instyle Traders Limited | Wholesale & retail | 2020 |
| Insulaadd Ltd | Construction | 2022 |
| Intandem Solutions Limited | Information & communication | 2003 |
| Inteducation Ltd | Education | 2016 |
| Integra Investment Ltd | Other services | 2017 |
| Integra Security Group Ltd | Administrative & support | 2018 |
| Integral Medical Centre Limited | Health & social care | 2008 |
| Intelekt Europe Limited | Professional & scientific | 2001 |
| Intelipath Ltd | Information & communication | 2011 |