| 00160692 Limited | | 1919 |
| 01 Digital Solutions Limited | Information & communication | 2002 |
| 4C Electronics Limited | Manufacturing | 1979 |
| A.Buckler Haulage Limited | Construction | 1960 |
| A1 Coaches Cleveland Limited | Information & communication | 2002 |
| A2I Technologies Limited | Information & communication | 2004 |
| Abbie Udall Associates Limited | Health & social care | 2018 |
| Acklam Car Centre Limited | Wholesale & retail | 2001 |
| AD77 Ltd | Financial services | 2021 |
| Adcas (1997) Limited | Manufacturing | 1997 |
| Agne Limited | Manufacturing | 2007 |
| Aldersyde Nursery Limited | Education | 2002 |
| Allomo Limited | Wholesale & retail | 2025 |
| Alta Vista Global Limited | Construction | 2006 |
| Amos Swift & Company,Limited | Manufacturing | 1926 |
| AP Welding and Fabrication Services Limited | Construction | 2017 |
| Apec Electrical Services Limited | Construction | 2006 |
| Aquarium Developments Ltd | Construction | 2007 |
| Art Therapy North East CIC | Health & social care | 2020 |
| Ashton Financial Services Limited | Financial services | 2003 |
| Astrohilt Limited | | 1982 |
| Astronaut Billingham Ltd | Hospitality | 2003 |
| Avant Garde Computers Limited | | 1993 |
| AWS Financial Solutions Limited | Financial services | 2007 |
| B Marshall Engineering Limited | Manufacturing | 2007 |
| Bespoke Will Writing Limited | Financial services | 2025 |
| Billcrest Limited | Mining & quarrying | 1993 |
| Billingham Masonic Hall and Club Limited | Other services | 1965 |
| BJP Corporation Ltd | Administrative & support | 2007 |
| Blema Limited | Wholesale & retail | 2026 |
| Blue Raven Limited | Professional & scientific | 2007 |
| Boathouse Machine Company Limited | Manufacturing | 2012 |
| Brooks Grocery & Offsales Ltd | Wholesale & retail | 1997 |
| BT Electrical Engineering Services Ltd. | Professional & scientific | 2007 |
| Bygones Bakery | | 1992 |
| C M Payrolls Limited | Information & communication | 1977 |
| Calmyes Ltd | Wholesale & retail | 2025 |
| Carlton Cinema (Guisborough) Limited | Construction | 1956 |
| Carlton-Sturman (Insurance Brokers) Limited | Financial services | 1975 |
| Charlie FOX Limited | Real estate | 1985 |
| Chipchase Manners Nominees Limited | Professional & scientific | 2001 |
| Chris Cook Ltd | Arts & recreation | 2010 |
| Christine O'Connor Cleaning Ltd | Administrative & support | 2005 |
| Chuhan & Singh Partnership Limited | Professional & scientific | 2007 |
| Clean & Shine (North East) Limited | Administrative & support | 2007 |
| Cleveland Auto Services & Hire Co. Ltd | Wholesale & retail | 2002 |
| Cleveland Cable Company Limited | Wholesale & retail | 2005 |
| Cleveland Pipework Services Limited | Wholesale & retail | 1979 |
| Cleveland Potash 1978 Pension Trustees Limited | Administrative & support | 2023 |
| Cleveland Technical Services (UK) Ltd | Professional & scientific | 1995 |
| Clevestone Plant Hire Ltd | Transport & logistics | 2020 |
| Clevestone Transport Ltd | Transport & logistics | 2020 |
| Clevestones Trans Limited | Transport & logistics | 1974 |
| Coinote International Limited | Wholesale & retail | 2006 |
| Complete Shielding Services Limited | Construction | 2003 |
| Coreq SHE Limited | Professional & scientific | 2007 |
| Cork Civil Engineering Limited | | 1975 |
| Cotec Technology Limited | Manufacturing | 2002 |
| Coultas & Shaw (1938) Limited | Construction | 1938 |
| Cowells - Arrow Bingo Company | | 1992 |
| Cowie Scientific Limited | Professional & scientific | 1994 |
| CPD Bodies Limited | Manufacturing | 2002 |
| Croft Fisheries Limited | Hospitality | 1999 |
| Crompton and Rouse Limited | Administrative & support | 2007 |
| D & H Sales | | 1990 |
| Dabro Limited | Professional & scientific | 2006 |
| Dale IAN Limited | Wholesale & retail | 2025 |
| David Kitchen Associates Limited | Professional & scientific | 1988 |
| DE Groot Engineering Limited | Professional & scientific | 1979 |
| DE Groot Installations (U.K.) Limited | Professional & scientific | 1980 |
| Deanswood Properties Limited | Real estate | 1989 |
| Deckair Limited | Manufacturing | 2003 |
| Develop Training Limited | Education | 2007 |
| Diocesan Property Management Limited | Construction | 1994 |
| DMP Solutions Limited | Information & communication | 2000 |
| Donald Hall Heating Limited | | 1969 |
| Drillsafe Limited | Wholesale & retail | 2018 |
| Driveshield Installations Limited | Administrative & support | 2006 |
| Dynospeed Agencies Ltd | Professional & scientific | 1998 |
| E & C Cook Limited | Wholesale & retail | 2015 |
| East Cleveland M.S. Home | Health & social care | 1987 |
| East Durham Funeral Service Ltd | Other services | 2007 |
| East Durham Manufacturing and Engineering Company Limited | Manufacturing | 1994 |
| Ecosurv Build Ltd | Wholesale & retail | 2004 |
| Edmond Smith Properties Ltd | Administrative & support | 1979 |
| Elring Klinger (Great Britain) Limited | Manufacturing | 1987 |
| Elysha Louise Limited | Wholesale & retail | 2025 |
| Empress Trading Limited | Wholesale & retail | 1998 |
| Enricos Hair Design Company Limited | Other services | 2011 |
| Erimus Securities Holdings Limited | Professional & scientific | 2007 |
| Executive Housing Developments Limited | Other services | 2006 |
| Ezcad Limited | Professional & scientific | 2007 |
| F Jones (Cleveland) Limited | Manufacturing | 1982 |
| F. Brunton & Sons Limited | Agriculture & fishing | 1955 |
| Fairs Travel Limited | Administrative & support | 1982 |
| Felixarc Marine Limited | Administrative & support | 2000 |
| Flaxton Street Wrought Iron Limited | Manufacturing | 2007 |
| Forman Metal Products Limited | Manufacturing | 1976 |
| Forrest Digital Limited | Professional & scientific | 2003 |
| Foxsands Investments Limited | Real estate | 1950 |