Grinnell Mutual is a property-casualty mutual insurance company and reinsurer based in Grinnell, Iowa, United States.
In 1909, the company was formed in Greenfield, Iowa as "Iowa Farmers Mutual Reinsurance Association" by John Evans to provide reinsurance for county mutuals in Iowa. In 1933, the company moved to Grinnell, Iowa, and changed its name to "Farmers Mutual Reinsurance Association". The name changed again in 1948 to "Farmers Mutual Reinsurance Company". The current legal name, "Grinnell Mutual Reinsurance Company," was adopted in 1963. The company adopted the “Grinnell Mutual” and “Grinnell Re" brands in 2017.
In 2014, Grinnell Mutual was one of first six companies investing in the Global Insurance Accelerator, the first startup accelerator for insurtech.
In response to the COVID-19 pandemic, Grinnell Mutual announced the Trust in Tomorrow Premium Payback. This was one of a series of actions in March–May 2020 to assist policyholders affected by the pandemic, including moratoriums on policy cancellations and other actions to help both auto and commercial policyholders through this unsettled time.