| I D Property Limited | Hamilton | 2011 |
| I DID a Thing Limited | Southend On Sea | 2024 |
| I DO & I DID Ltd | Rochester | 2024 |
| I DO I DO I DO Ltd | Manchester | 2023 |
| I DO Marketing Ltd | Faversham | 2024 |
| I Effendi Limited | Cleckheaton | 2025 |
| I Fell OFF Limited | Hamilton | 2018 |
| I FIX Norway Limited | London | 2021 |
| I Four Branding Ltd | Tugby | 2020 |
| I G I Developments Limited | Eastleigh | 2006 |
| I Go Entertainment Ltd | London | 2013 |
| I H T Planning Limited | Swansea | 2008 |
| I Holland Holdings Limited | Nottingham | 2015 |
| I Link Couriers Ltd | Bristol | 2014 |
| I Love Artisan Markets Ltd | Worcester | 2003 |
| I Love Fancy Dress Limited | Canvey Island | 2018 |
| I Love Harris Tweed Ltd | Falkirk | 2010 |
| I Love LDN Limited | London | 2020 |
| I Love Markets Ltd | Worcester | 2005 |
| I Love Tax, SO YOU Don'T Have to Limited | Wells | 2022 |
| I Love to Learn Professional Tuition (Fareham) Ltd | Portsmouth | 2023 |
| I Love Wallpaper Ltd | Hartlepool | 2021 |
| I Ltd | Newmarket | 2021 |
| I M & T Associates Limited | Bromsgrove | 1994 |
| I Move IT on Limited | Redditch | 2015 |
| I Musicanti Limited | Tring | 2012 |
| I P Results Limited | Mansfield | 2010 |
| I Q Solutions (South West) Limited | Bleadon | 2012 |
| I R Patel Housing Limited | London | 2025 |
| I R S Superstaff Ltd. | London | 1996 |
| I S L Shield Ltd | Pride Park | 1996 |
| I S Media Limited | City Of Bristol | 2015 |
| I Scream and Shake Limited | Harlow | 2015 |
| I T R M Ltd | London | 1999 |
| I T Supplies (NE) Limited | Gateshead | 2020 |
| I W T Ltd. | Manchester | 1997 |
| I Wall Installations Limited | Cirencester | 2003 |
| I Want My Mummy Ltd | Coventry | 2015 |
| I Want to Buy a Car Limited | Wickford | 2011 |
| I Wish I HAD Limited | Tunbridge Wells | 2000 |
| I Work in Europe Limited | Hove | 2014 |
| I&F Securities Limited | London | 2013 |
| I&G Surfacing Ltd | London | 2018 |
| I&S Contracting Ltd | Wrexham | 2022 |
| I'M After Ltd | Petersfield | 2017 |
| I'M Back Limited | Romford | 2020 |
| I'M NO Expert Limited | Hook | 2025 |
| I-Accountancy Limited | Bromsgrove | 2016 |
| I-Financial Services Limited | Harpenden | 2000 |
| I-Fit Golf Limited | Bedford | 2023 |
| I-Growhydro Ltd | Orpington | 2017 |
| I-Kandy Ltd | London | 2025 |
| I-Kraft Joiners Limited | Dewsbury | 2023 |
| I-Legal Services Limited | Harpenden | 2001 |
| I-Net Networks Limited | London | 2009 |
| I-Payout London Limited | London | 2022 |
| I-Payroll Services Limited | Harpenden | 2000 |
| I-Peaks Ltd | Coventry | 2024 |
| I-Slide Limited | Warrington | 2013 |
| I-Smart Developments China Limited | Leamington Spa | 2022 |
| I-Taxation Services Limited | Harpenden | 2000 |
| I-Tech Electronics Ltd. | London | 2018 |
| I-Uplift Limited | Tranent | 2017 |
| I-V-K Image Co Limited | Stafford | 2013 |
| I-West-Car Limited | London | 2025 |
| I. G. Employee Share Trustee Limited | Newport Pagnell | 1998 |
| I. Wilkes Electrical Services Limited | Cramlington | 2016 |
| I.B. Atlas Limited | London | 2013 |
| I.B.C. Transport Containers Limited | Norwich | 1966 |
| I.C.E.L. Power Systems Limited | Newcastle Upon Tyne | 2000 |
| I.D. & S. Dunbar Limited | Nottingham | 2002 |
| I.D.S. U.K. Limited | Sudbury | 2008 |
| I.G.O. Limited | London | 1990 |
| I.G.P.I. Services Ltd | Birmingham | 2020 |
| I.I.R.C. Limited | Saltburn By The Sea | 1999 |
| I.J. Parkash (U.K.) Limited | Cheadle | 1985 |
| I.M. NO. 10 Limited. | Leeds | 1899 |
| I.M. Properties Finance Limited | Solihull | 1992 |
| I.M.E.R. - Reman Limited | Coventry | 1995 |
| I.S. 16 Harper Road Limited | London | 2025 |
| I.S. Group (Europe) Limited | London | 1998 |
| I.S. Harper Road Limited | London | 2025 |
| I.S. Highgate Investment Limited | London | 2025 |
| I.S. Highgate Limited | London | 2023 |
| I.S. Southwark Investments Limited | London | 2025 |
| I.S.D. Cold Stores Limited | Gloucester | 1952 |
| I.T. Campaign | London | 2011 |
| I.T. Consortium Limited | Reading | 1999 |
| I.T. Investments Ltd | Nantwich | 2007 |
| I2 Managed Print Solutions Ltd | London | 2024 |
| I3S Limited | Derbyshire | 2003 |
| I3VISION Limited | Bromsgrove | 2014 |
| I43 Ltd | Ilford | 2024 |
| I4W Promotions Ltd | Coleraine | 2014 |
| I6 Clouds Limited | Farnborough | 2015 |
| I6 Limited | Farnborough | 2021 |
| I6 Marine Limited | Farnborough | 2015 |
| I6 Military Limited | Farnborough | 2015 |
| I6 Optimise Limited | Farnborough | 2015 |
| I6 Refuel Limited | Farnborough | 2015 |