Calvo’s Insurance was founded by the late Edwardo T. Calvo as a sideline business in 1938. Mr. Calvo was the Assistant Manager of the old Bank of Guam when he started the small insurance operation in his name. He signed an insurance agency agreement with the late Jack Smith, one of the original partners of Cornelius V. Starr, founder of the American International Group (AIG), a company which now operates in over 150 countries and territories around the world and has become the largest commercial insurer in the United States.

Mr. Calvo’s insurance operation was interrupted for three years by World War II. Following the liberation of Guam in 1944, E. T. Calvo resigned his position with the Bank of Guam, which was then taken over by the Bank of America, and reestablished his insurance agency. His small agency grew progressively over the years. Today, Calvo’s Insurance is the island's oldest and largest insurance company with two separate divisions handling both the Property & Casualty and Life & Health operations of the insurance arena. In addition, Calvo’s Insurance maintains offices in Dededo, Saipan, Palau and the Philippines.