2022 payable 2023 real estate installment dates have been set in Mercer County. The first payment is due June 23 with the second and final payment set for September 8. Payments can be mailed to Mercer County Collector’s Office, 100 SE 3rd Street, Aledo, IL 61231. There are also drop boxes at the Mercer County Courthouse. In addition, you can make payments at Mercer County area banks. You can also pay online at mercercountyil.org.