| Cambridge Maintenance Ltd | Construction | 2023 |
| Cambridge Make and Grow Ltd | Wholesale & retail | 2015 |
| Cambridge Management and Leadership School Ltd | Education | 2017 |
| Cambridge Management and Research Ltd | Extraterritorial | 2003 |
| Cambridge Management Consultants Limited | Professional & scientific | 1985 |
| Cambridge Management Consulting (Finance) Limited | Administrative & support | 2020 |
| Cambridge Management Consulting Limited | Professional & scientific | 2015 |
| Cambridge Management Consulting Partners LLP | | 2019 |
| Cambridge Manufacturing Solutions Limited | Professional & scientific | 2010 |
| Cambridge Marketing College Limited | Education | 1991 |
| Cambridge Marketing Consultancy Ltd | Professional & scientific | 2015 |
| Cambridge Marketing Strategy Limited | Administrative & support | 2008 |
| Cambridge Masonic Hall Limited | Real estate | 1959 |
| Cambridge Matrix Ltd | Professional & scientific | 2021 |
| Cambridge MC Limited | Professional & scientific | 2020 |
| Cambridge Mechatronics Limited | Professional & scientific | 1995 |
| Cambridge Media Group Limited | Information & communication | 1999 |
| Cambridge Medical Academy Ltd | Health & social care | 2014 |
| Cambridge Medical AI Solutions Ltd | Information & communication | 2025 |
| Cambridge Medical Care Limited | Health & social care | 2022 |
| Cambridge Medical Consulting Ltd | Health & social care | 2026 |
| Cambridge Medical Education Limited | Construction | 2013 |
| Cambridge Medical Genomics Ltd | Professional & scientific | 2013 |
| Cambridge Medical Robotics Limited | Extraterritorial | 2018 |
| Cambridge Medical Sensor Limited | Professional & scientific | 2023 |
| Cambridge Medical Systems Limited | Extraterritorial | 2002 |
| Cambridge Medical Training Limited | Education | 2010 |
| Cambridge Medtech Ltd. | Manufacturing | 2013 |
| Cambridge Memory Trading Limited | Wholesale & retail | 2010 |
| Cambridge Mercury Properties Ltd | Real estate | 2024 |
| Cambridge Metalweld Limited | Manufacturing | 2010 |
| Cambridge Metrics Solutions Ltd | Information & communication | 2014 |
| Cambridge Microelectronics Ltd | Professional & scientific | 2012 |
| Cambridge Microfab Limited | Manufacturing | 1991 |
| Cambridge MID Century Limited | Wholesale & retail | 2018 |
| Cambridge Middle East Ltd | Hospitality | 2021 |
| Cambridge Midsummer Apartments Limited | Hospitality | 2012 |
| Cambridge Mini Market Ltd | Wholesale & retail | 2025 |
| Cambridge MK Limited | Real estate | 2017 |
| Cambridge MMA Ltd | Arts & recreation | 2022 |
| Cambridge Mobilytics Limited | Information & communication | 2025 |
| Cambridge Model 2021 Limited | Financial services | 2023 |
| Cambridge Molecular Computers Ltd | Professional & scientific | 2025 |
| Cambridge Molecular Diagnostics Ltd | Professional & scientific | 2015 |
| Cambridge Molecular Ltd | Information & communication | 2019 |
| Cambridge Money Coaching Ltd | Other services | 2018 |
| Cambridge Montessori Ltd | Education | 2016 |
| Cambridge Montessori Preschool and Daycare Ltd | Education | 2017 |
| Cambridge Motorcycles Limited | Wholesale & retail | 2006 |
| Cambridge Motoring School Ltd | Education | 2025 |
| Cambridge Music & Tech Ltd | Professional & scientific | 2011 |
| Cambridge Music Festival Ltd | Arts & recreation | 1993 |
| Cambridge Music Ltd. | Extraterritorial | 2011 |
| Cambridge Music Therapy Ltd | Real estate | 2023 |
| Cambridge Muslim Academy Ltd | Education | 2021 |
| Cambridge Muslim College Limited | Education | 2009 |
| Cambridge Muslim College Press Ltd | Information & communication | 2024 |
| Cambridge Muslim Secondary School | Education | 2025 |
| Cambridge Nano Ltd | Professional & scientific | 2011 |
| Cambridge Nanomaterials Technology Ltd | Professional & scientific | 2009 |
| Cambridge Natural Supplements Limited | Wholesale & retail | 2020 |
| Cambridge Network Limited | Other services | 1997 |
| Cambridge Neuro Rehab Ltd | Health & social care | 2022 |
| Cambridge Neuro Science Ltd. | Professional & scientific | 2025 |
| Cambridge Neuro-Physiotherapy Ltd | Other services | 2012 |
| Cambridge Neuropsychology Ltd | Professional & scientific | 2025 |
| Cambridge Neurotech Ltd | Professional & scientific | 2013 |
| Cambridge New Media Limited | Information & communication | 2003 |
| Cambridge Novolab Limited | Health & social care | 2021 |
| Cambridge NPD Ltd | Extraterritorial | 2018 |
| Cambridge Nucleomics Ltd | Professional & scientific | 2021 |
| Cambridge Nutraceuticals Limited | Health & social care | 2010 |
| Cambridge Nutranostics Limited | Professional & scientific | 2014 |
| Cambridge Nutrition and Lifestyle Medicine Ltd | Health & social care | 2023 |
| Cambridge OCR | Education | 1997 |
| Cambridge Oncology Ltd | Professional & scientific | 2018 |
| Cambridge Oncology Partners LLP | | 2014 |
| Cambridge Online | Education | 1998 |
| Cambridge Online Flooring Ltd | Wholesale & retail | 2025 |
| Cambridge Online Learning Limited | Education | 2021 |
| Cambridge Online Trading Limited | Education | 2011 |
| Cambridge Online Tuition Limited | Education | 2023 |
| Cambridge Open Studios | Arts & recreation | 1997 |
| Cambridge Opera Limited | Arts & recreation | 2026 |
| Cambridge Optical Services Limited | Health & social care | 2018 |
| Cambridge Oriental Trusts | Arts & recreation | 2003 |
| Cambridge Orthopaedic Services Limited | Health & social care | 2011 |
| Cambridge Osteopathy Limited | Health & social care | 2022 |
| Cambridge Otology-Neurotology Limited | Health & social care | 2017 |
| Cambridge Overseas Ltd | Hospitality | 2010 |
| Cambridge Padel Ltd | Arts & recreation | 2025 |
| Cambridge Padel Tennis Club Ltd | Arts & recreation | 2025 |
| Cambridge Paediatric Medicolegal Associates Ltd | Professional & scientific | 2020 |
| Cambridge Paint Masters Ltd | Construction | 2026 |
| Cambridge Painting & Decorating Ltd | Construction | 2026 |
| Cambridge Papers Limited | Information & communication | 1995 |
| Cambridge Park & Leisure Homes Limited | Hospitality | 2018 |
| Cambridge Partners Ltd | Professional & scientific | 2020 |
| Cambridge Past, Present & Future | Arts & recreation | 1929 |
| Cambridge Pelvic Clinic Limited | Health & social care | 2026 |