Houston is a county seat located in the Texas region of the United States. During the most recent census, Houston had a population of 2,099,451. Houston is the most poplulated city in the Texas region, the 5th most populated city in the United States and the 128th most populated city in the world. Houston is in the America/Chicago timezone which is 5 hours behind UTC. Houston adjusts the hour with daylight savings time during the winter months.