Bethlehem is a city in Northampton and Lehigh Counties in the Lehigh Valley region of eastern Pennsylvania, United States. As of the 2020 census, Bethlehem had a total population of 75,781, making it the second-largest city in the Lehigh Valley after Allentown and the seventh-largest city in the state. Among its total population as of 2020, 55,639 were in Northampton County and 19,343 were in Lehigh County.