Thomas was named for William Thomas, who owned a general store and served as postmaster, when the first post office was established at the store on February 12, 1894, while this area was part of Oklahoma Territory.

The Oklahoma Railway Townsite platted Morris' land in 1902, the same year that the Blackwell, Enid and Southwestern Railroad (later the St. Louis and San Francisco Railway) constructed a line through Thomas.

Most of the early settlers were members of the Amish, the Dunkards, and the Church of the United Brethren in Christ religious groups.

[4] According to the United States Census Bureau, the city has a total area of 1.2 square miles (3.1 km2), all land.

According to the Encyclopedia of Oklahoma History and Culture, Over 91 percent of the employed residents commute to work in other communities.

Formerly known as the Barrett Refinery and opened in 1982,[6] this facility has a rated capacity of 14,000 barrels per day.

After the Barrett Company declared bankruptcy, the refinery was scheduled to close permanently on December 22, 2005.

Revival of the refinery was expected to open up about 30 to 50 new local jobs, excluding personnel needed to drive about 30 trucks handling product deliveries per day.