| CIM Consultancy Ltd | Professional & scientific | 2009 |
| Cinagro Enterprise Ltd | Real estate | 2023 |
| Cindercone Solutions Limited | Information & communication | 2002 |
| Cinderella EYT Cleaning Services Limited | Administrative & support | 2025 |
| Cinderhouse Creative Ltd | Information & communication | 2021 |
| Cinnammmm Ltd | Wholesale & retail | 2024 |
| Cinnamon Banqueting Limited | Hospitality | 2023 |
| Cinnamon Core Solutions Ltd | Information & communication | 2025 |
| Cinnamon Express (Horbury) Limited | Hospitality | 2023 |
| Cinnamon Recruitment Limited | Administrative & support | 2006 |
| Cinnamon Systems Limited | Information & communication | 1997 |
| Cinnamon Yeadon Limited | Hospitality | 2018 |
| Cinzia Procter Counselling and Psychotherapy Ltd | Health & social care | 2026 |
| Ciocinta Couriers Ltd | Transport & logistics | 2026 |
| CIP Healthcare Services Limited | Health & social care | 2019 |
| Cipher Intelligence Group Ltd | Wholesale & retail | 2023 |
| Cipher Property Investments Limited | Real estate | 2019 |
| Ciphyr Ltd | Professional & scientific | 2025 |
| Cippyhq UK Ltd | Administrative & support | 2025 |
| Ciprian Gangal Limited | Transport & logistics | 2025 |
| Ciprianz Ltd | Transport & logistics | 2019 |
| Circle 365 Recruitment Limited | Administrative & support | 2015 |
| Circle 8 Massage Ltd | Health & social care | 2015 |
| Circle Homes ( U.K ) Limited | Real estate | 2023 |
| Circle John Ltd | Wholesale & retail | 2024 |
| Circle Studio Ltd | Construction | 2020 |
| Circle Techno Ltd | Wholesale & retail | 2023 |
| Circle Training Ltd | Information & communication | 2020 |
| Circles of Life Voice of Women CIC | Administrative & support | 2024 |
| Circles Training & Consultancy Limited | Health & social care | 2006 |
| Circular Fashion Incubator CIC | Administrative & support | 2024 |
| Circular North Advisory Ltd | Professional & scientific | 2025 |
| Circularity Furniture Ltd | Manufacturing | 2024 |
| Circulate Roastery Limited | Other services | 2021 |
| Circus Developments (Bradford) Ltd | Real estate | 2019 |
| Circus Developments (Hull) Ltd | Construction | 2024 |
| Circus Investments Ltd | Real estate | 2022 |
| Circus Leeds | Arts & recreation | 1994 |
| Circus PPC Agency Ltd | Professional & scientific | 2012 |
| Circus Regen Limited | Construction | 2021 |
| Cire 10 Limited | Hospitality | 2022 |
| Cirell Consulting Ltd | Professional & scientific | 2010 |
| Cirp Enterprises Limited | Real estate | 2021 |
| Cirraum Limited | Real estate | 2015 |
| Cirrus Charlie Delta Limited | Arts & recreation | 2017 |
| Cirrus UK Group Limited | Professional & scientific | 2023 |
| Cirrusdock Ltd | Information & communication | 2024 |
| Cistermiser Limited | Manufacturing | 1979 |
| Citadel EDU Group UK Ltd | Professional & scientific | 2026 |
| Citeco Group Ltd | Financial services | 2026 |
| Citeco Ltd | Construction | 2026 |
| Citi Plus Logistics and Transport Limited | Transport & logistics | 2026 |
| Citicharge Limited | Construction | 2021 |
| Citiflex PLC | Financial services | 1997 |
| Citigarden Living Limited | Hospitality | 2018 |
| Citipadel Limited | Real estate | 1995 |
| Citipads Limited | Real estate | 2016 |
| Citipark Management Limited | Financial services | 2014 |
| Citipark PLC | Financial services | 2014 |
| Citiplay Limited | Other services | 2003 |
| Citispace Convenience Ltd | Wholesale & retail | 2023 |
| Citispace Group Limited | Real estate | 2004 |
| Citispace Lettings + Management Limited | Real estate | 2026 |
| Citispace Services Limited | Real estate | 2004 |
| Citizen Science CIC | Education | 2023 |
| Citizens of Light Church Ltd | Other services | 2024 |
| Citrefine International Limited | Wholesale & retail | 1994 |
| Citrian Holdings Limited | Professional & scientific | 2014 |
| Citrus Connect Ltd | Administrative & support | 2009 |
| Citu (District Lofts) Ltd | Real estate | 2024 |
| Citu (Kelham Island) LLP | | 2012 |
| Citu (LOW Fold) LLP | | 2013 |
| Citu Developments LLP | | 2012 |
| Citu Group Developments Ltd | Professional & scientific | 2013 |
| Citu Group Ltd | Professional & scientific | 2016 |
| Citu LOW Fold Leeds Ltd | Professional & scientific | 2014 |
| City & Capital Headhunters Limited | Professional & scientific | 2016 |
| City & Capital Property Limited | Real estate | 2019 |
| City & General Direct (U.K.) Limited | Administrative & support | 1998 |
| City ADS (Leeds) Limited | Professional & scientific | 2009 |
| City and Guilds Kineo Limited | Information & communication | 2010 |
| City Beauty Limited | Other services | 2023 |
| City Cabs Leeds Ltd | Transport & logistics | 2020 |
| City Central (Leeds) RTM Company Limited | Households | 2007 |
| City Central Leeds Freehold Limited | Real estate | 2020 |
| City Chippy Limited | Hospitality | 2004 |
| City Cleaning Ltd | Administrative & support | 2009 |
| City Climbing Company Ltd | Arts & recreation | 2008 |
| City Coast Country Property Trading (Cccpt) Ltd | Real estate | 2025 |
| City Elite Cars Ltd | Transport & logistics | 2022 |
| City Estate Group Limited | Real estate | 2018 |
| City Estate Holding Limited | Real estate | 2019 |
| City Estate Rocker Ltd | Real estate | 2020 |
| City Estate Sunderland Limited | Real estate | 2018 |
| City Evangelical Church, Leeds | Other services | 2011 |
| City Express International Limited | Professional & scientific | 2024 |
| City Express Logistics Ltd | Transport & logistics | 2008 |
| City Fashion Week Limited | Extraterritorial | 2013 |
| City Force Healthcare Ltd | Other services | 2016 |
| City Fusion Limited | Real estate | 1978 |