As of the 2020 Census, the population of Illinois was approximately 12,812,508. Illinois is allocated 18 seats in the U.S. House of Representatives. Therefore, the population per house seat in Illinois is approximately 712,917 people per seat.
According to the US Census, there are 902,195 residents for each Montana house seat.
According to the US Census, there are 639,088 residents for each California house seat.
According to the US Census, there are 651,619 residents for each Texas house seat.
According to the US Census, there are 639,295 residents for each Florida house seat.
According to the US Census, there are 630,730 residents for each Ohio house seat.
According to the US Census, there are 629,727 residents for each Georgia house seat.
According to the US Census, there are 662,563 residents for each Michigan house seat.
According to the US Census, there are 643,501 residents for each Virginia house seat.
According to the US Census, there are 654,902 residents for each Washington house seat.
According to the US Census, there are 634,910 residents for each Massachusetts house seat.
According to the US Census, there are 641,329 residents for each Arizona house seat.