Markham is located in Illinois. Markham, Illinois has a population of 12,649. Markham is less family-centric than the surrounding county with 16.97% of the households containing married families with children. The county average for households married with children is 30.49%.
The median household income in Markham, Illinois is $35,200. The median household income for the surrounding county is $59,426 compared to the national median of $57,652. The median age of people living in Markham is 37.4 years.
The average high temperature in July is 83.9 degrees, with an average low temperature in January of 15.6 degrees. The average rainfall is approximately 39.3 inches per year, with 27.8 inches of snow per year.