Safeco was founded in 1923 by Hawthorne Kingsbury Dent (1880-1958) as the General Insurance Company of America, a property and casualty insuring company, with a headquarters in Downtown Seattle at the corner of University Street and Fourth Avenue.

In 1953, it formed a subsidiary, the "Selective Auto and Fire Insurance Company of America," or SAFECO.

In 1968, it changed its name from the General Insurance Company of America to Safeco Corporation.

[10] In August 2004, the company sold its life insurance and investments business to a group of private investors led by Safeco board members, Warren Buffett's Berkshire Hathaway, and White Mountains Insurance Group, incorporating as Symetra.

[12] Mellon Financial acquired Safeco Trust Company, its private bank.

[24] Safeco held the naming rights to the Seattle Mariners' baseball stadium from its opening in July 1999 through the 2018 season.

[25] The company also sponsored the Safeco Classic, a women's professional golf tournament on the LPGA Tour from 1982 through 1999; it was held in September at the Meridian Valley Country Club in Kent.