Medical Mutual of Ohio (MMOH) is an insurance company based in Cleveland, Ohio. Established in 1934, the company provides property, casualty, health, and life insurance services to individuals, families, and groups in the United States. It also offers individual and family health plans, Medicare supplement insurance plans, third-party administrative services to self-insured group customers, and a range of employer-provided group health insurance plans for employers and employees. The assets of the company are managed by the board of directors.