John Thomas Averill (March 1, 1825 – October 3, 1889) was a United States Army officer in the American Civil War who later became a U.S. congressional representative from Minnesota.

In 1852 he moved to northern Pennsylvania and again engaged in lumbering until 1857, when he settled in Lake City, Minnesota.

He was promoted to colonel on November 22, 1864, and was assigned as Provost Marshal General for the District of Minnesota.

He was honorably mustered out on September 28, 1865; and was made a brevet brigadier general on October 18, 1865.

[1] Averill resumed his business activities in St. Paul, Minnesota, where he died on October 3, 1889; interred at the Oakland Cemetery.