| Caledonia Investments PLC | London | 1928 |
| Caledonia Leasing Ltd | Turriff | 2023 |
| Caledonia Limited | | 2003 |
| Caledonia Mortgages Limited | Glasgow | 2015 |
| Caledonia Offshore Wind Farm Holding Limited | London | 2022 |
| Caledonia Property Holdings Ltd | Glasgow | 2026 |
| Caledonia Red Holdings Limited | Grangemouth | 2024 |
| Caledonia US Investments Limited | London | 2020 |
| Caledonian Consumer Finance Ltd | Carlisle | 2010 |
| Caledonian Dragon Limited | Whiteley | 2021 |
| Caledonian Financial Management Limited | Glasgow | 2005 |
| Caledonian Global Group UK Ltd | Inverurie | 2024 |
| Caledonian Global Investments Ltd | Inverurie | 2024 |
| Caledonian Group (Scotland) Ltd | Falkirk | 2022 |
| Caledonian Lifts Holdings Limited | Glasgow | 2018 |
| Caledonian Loans Limited | Carlisle | 2015 |
| Caledonian Packaging (Holdings) Limited | Midlothian | 2005 |
| Caledonian Rail Leasing Limited | London | 2014 |
| Caledonian Road VOV Holdings Ltd | London | 2023 |
| Caledonian Sleepers Rail Leasing Limited | London | 1985 |
| Caledonian Wind Limited | Newport | 2010 |
| Calem Consultants Ltd | London | 2008 |
| Calendar Holdings Ltd | London | 2023 |
| Calendula Ventures Limited | London | 2022 |
| Calenergy GAS (Holdings) Limited | Newcastle Upon Tyne | 1992 |
| Calenergy Resources (Operator) Limited | Newcastle Upon Tyne | 2024 |
| Calentra Holdings Limited | Kilmarnock | 2026 |
| Caleo Holdings Limited | Harbour Walk | 2025 |
| Calereux Properties Limited | Spalding | 2026 |
| Calesa Developments Holdings Ltd | Derby | 2025 |
| Caleus London I Holding Limited | Brighton | 2021 |
| Caleus London I Property Limited | Brighton | 2021 |
| Calex Electronics EOT Limited | Leighton Buzzard | 2025 |
| Caley Cold Store (Holdings) Limited | Peterhead | 2021 |
| Caley Water Holdings Ltd | Edinburgh | 2024 |
| Calf HEY Holdings Limited | Huddersfield | 1996 |
| Calf HEY Labels Limited | Huddersfield | 2021 |
| Calfin Limited | London | 2011 |
| Calgarth Holdings Ltd | Manchester | 2025 |
| Calgi Partners Ltd | London | 2017 |
| Caliber Consultancy Limited | Birmingham | 2023 |
| Caliber Financial Associates Limited | Ampthill | 2001 |
| Caliber Financial Planning Limited | Chinnor | 2009 |
| Caliber Holdings Ltd | London | 2025 |
| Caliber Media Holdings Limited | London | 2022 |
| Caliber Ophthalmics (UK) Limited | Cheltenham | 2019 |
| Caliber Wealth Management Limited | Milton Keynes | 2006 |
| Calibra Services Limited | Preston | 2023 |
| Calibrate Management Limited | London | 2015 |
| Calibre Capital Mortgage Finance Limited | London | 2013 |
| Calibre Conservation Ltd | Lincoln | 2017 |
| Calibre Financial Solutions Limited | Bradford | 2020 |
| Calibre Group Holdings Limited | Kings Langley | 2024 |
| Calibre Professional Services Limited | London | 2014 |
| Calibre Redhill Limited | Epsom | 2013 |
| Calibro Holdings Limited | Bristol | 2020 |
| Calibso Holdings Limited | Windsor | 2021 |
| Calico Capital Limited | London | 2015 |
| Calico Wealth Management Limited | Buxton | 2014 |
| Calidad Holdings Limited | Barnsley | 2015 |
| Califino Limited | Gloucester | 2017 |
| California Bidco Limited | Hemel Hempstead | 2018 |
| California Holding II Limited | London | 2022 |
| California Holding IV Limited | London | 2023 |
| California Holding Limited | London | 2022 |
| California Holding V Limited | London | 2023 |
| California Manco Limited | London | 2024 |
| California Midco Limited | Hemel Hempstead | 2018 |
| California Sacramento Limited | Sandy | 2016 |
| California Topco Limited | Hemel Hempstead | 2018 |
| Californialilac Ltd | Newcastle | 2025 |
| Caligari-X Ltd | London | 2025 |
| Caligo Group Ltd | Brentford | 2024 |
| Caligran Holdings Limited | Mansfield | 2021 |
| Caligroup Limited | Bath | 2025 |
| Calil Ltd | London | 2019 |
| Calima Capital Limited | London | 2023 |
| Calimantana Limited | Erith | 2024 |
| Calinette Limited | Bath | 2020 |
| Calis Holding Ltd | Sheffield | 2024 |
| Calisbon Holdings Limited | Weybridge | 2026 |
| Calisen Group (Holdings) Limited | Manchester | 2020 |
| Calisen Holdco 2 Limited | Manchester | 2016 |
| Calisen Holdco 3 Limited | Manchester | 2016 |
| Calisen International Holdings Limited | Manchester | 2017 |
| Calisen Limited | Manchester | 2020 |
| Calisen Meter Serve Holdco Limited | Manchester | 2007 |
| Caliskan Holdings Ltd | London | 2025 |
| Calissia Management Ltd | London | 2020 |
| Calista Group Ltd | Cardiff | 2021 |
| Calitii Holdings Ltd | London | 2025 |
| Calix Investment (UK) Limited | London | 2020 |
| Call 2 Connect Ltd | London | 2006 |
| Call 4 Credit Limited | Stockton On Tees | 2006 |
| Call Assist Holdings Limited | Colchester | 2006 |
| Call Assist Limited | Colchester | 1998 |
| Call in SAY HI Ltd | Warrington | 2025 |
| Call Miss Jones Limited | Wrexham | 2018 |
| Call Protect Ltd | Oldham | 2023 |
| Callabas Financial Services Ltd | Burford | 2023 |