tarrant_county,_texas | countyseat | fort_worth,_texas <sep> tarrant county is located in the us state of texas as of 2020, it had a population of 2,110,640 it is texas' third-most populous county and the 15th-most populous in the united states its county seat is fort worth 
the county seat of tarrant county in texas is fort worth.tarrant county is texas' third-most populous county and the 15th-most populous in the united states