The median sales price for homes in Thornton IL for Sep 13 to Dec 13 was $103,750. This represents an increase of 44.1%, or $31,750, compared to the prior quarter and an increase of 71.5% compared to the prior year. Sales prices have depreciated 21.7% over the last 5 years in Thornton. The average listing price for Thornton homes for sale on Trulia was $67,564 for the week ending Dec 04, which represents a decline of 15.3%, or $12,206, compared to the prior week and a decline of 6.9%, or $5,010, compared to the week ending Nov 13. Average price per square foot for Thornton IL was $62, an increase of 37.8% compared to the same period last year.