Thomas was born in Columbus, Ohio, and moved to South Charleston as a child. He was a star football player at South Charleston High School and Virginia Tech.

In 1942, Thomas enlisted in the Marine Corps Reserve. He served with the 3rd Marine Division in the South Pacific and earned the Medal of Honor for his bravery during the Bougainville campaign. On November 7, 1943, he sacrificed his life by jumping on a grenade to save his squad after it bounced back towards them.

Thomas was awarded the Medal of Honor posthumously in 1944. The USS Herbert J. Thomas and a hospital in South Charleston were named in his honor. He is buried in South Charleston.