Monahans is a city in and the county seat of Ward County, Texas, United States. A very small portion of the city extends into Winkler County. T…Monahans is a city in and the county seat of Ward County, Texas, United States. A very small portion of the city extends into Winkler County. The population was 6,953 at the 2010 census. In 2018, the population was estimated at 7,669.