Welcome to Mercer County

Mercer County is located along U.S. Highway 67 and State Highways 17 and 94 in the U.S. state of Illinois. The Mississippi River is located along the western border of Mercer County and is part of the Yellowbanks Territory, named by the Sauk and Fox Indians because of the yellow, sandy soil along the riverbank. Named after Revolutionary War hero General Hugh Mercer, Mercer County was chartered in 1835 as part of the old Northwest Territory and the Military Tract. As of 2010, the population was 16,434 a drop of 523 from 2000. The county seat is Aledo. Mercer County is one of the four counties that make up the Davenport-Moline-Rock Island Metropolitan Statistical Area.

View of the Mississippi River in New Boston, IL


Agendas and Minutes for Committee & Board Meetings, as well as public forms and documents are posted on the Documents page.

Law Enforcement Agendas can be found on the Mercer County Sheriff's Office website.


Public Act

Per Public Act 97-0609, an amendment to the Open Meetings Act 5ILCS 120/7.3, it is the duty of all Illinois Municipal Fund Employers to post information for each employee having a total compensation package that exceeds $75,000.00 per year. This package is to include salary, health insurance, vacation and sick days granted.

These include:

  • States Attorney Grace Simpson , $138,603.00
  • Public Defender Andrew Larson, $80,000.00






Public Transportation

Mercer County Public Transportation


April 2021 Consolidated Election

If you would like to vote by mail for the April 6, 2021 Consolidated Election, please fill out an application and return it to our office to receive a ballot packet.

Early, Absentee, and Grace Period Voting information.




The Probation Office has an opening for a Probation Officer.  See job description for details.



The Courthouse is open to the public.  Masks are required and social distancing guidelines are being followed.  County offices can be found by clicking COVID-19 information.  Thank you for your cooperation and understanding during this time.





Notice to taxpayers

2021 Homestead Exemption Renewal

Currently, for all 2021 homestead exemptions renewals, such as The Senior Homestead Freeze, Disabled Vet and Disabled Persons exemptions:

The Mercer County Assessment office will be mailing all renewal forms to the taxpayer after April 1st 2021.

Contact Mary McClellan at 309-582-4747 or Taylor at 582-4818 for all questions or concerns. All completed exemption  forms  may be mailed to The Mercer County Assessment Office by 12-31-2021. The Mercer County Assessment Office address is: 100 SE 3rd Street, Aledo IL 61231.



Mercer County Treasurer office: Bev Lower

Click the following link to be directed to the Treasurer's page: https://www.illinoistreasurers.org/treshome.php?idCounty=14066

Tax Records can be searched online at merceril.devnetwedge.com

ALL property tax information can be found on the website.  (To search) less is best just a last name or house # and town

For 2019 Payable 2020 Property Tax Sale information see the Treasurer page of the website.

If you need to come in, please call (309)582-2524 to make an appointment or email lower@mercercountyil.org OR kris@mercercountyil.org, a mask will be required if you come into the office.

Please feel free to contact my office with any questions, we will assist you in any way we can.  Use our website for any new information, you can also access your property taxes online from our website and print your bill.

Thank you!  Stay safe, keep your families safe, and continue social distancing as long as possible.

Mercer County Treasurer Bev Lower



Zoning Board of Appeals meetings are held in the Board Room at the Mercer County Courthouse, 100 SE 3rd Street, Aledo, IL  61231





Photo Gallery

Light Box Content


Dialog example

This is dummy copy. It is not meant to be read. It has been placed here solely to demonstrate the look and feel of finished, typeset text. Only for show. He who searches for meaning here will be sorely disappointed.



Visit Mercer County

Upcoming Events

No events found.