Mercer County Property Records Lookup
Mercer County property records are managed by the Supervisor of Assessments in Aledo, the county seat. The office tracks assessed values, ownership details, and exemption filings for every parcel in the county. Township assessors handle the field work of inspecting properties and setting values, while the county office reviews those numbers for consistency. Mercer County is in western Illinois along the Mississippi River, and property here includes productive farmland, river bluff parcels, and small town lots. You can search records online through the DevNet Wedge portal, call the office, or stop by at 100 SE 3rd Street in Aledo to look up what you need in person.
Mercer County Property Records Quick Facts
Mercer County Assessment Office
Mary McClellan serves as the Supervisor of Assessments for Mercer County. Her office is at 100 SE 3rd Street in Aledo. This is the central office for property records in the county. Staff here maintain assessed values for all parcels, process exemption forms, and guide the township assessors who set values on the ground. Under 35 ILCS 200/, the Supervisor of Assessments must review township values and make sure they are uniform. If one area looks off compared to the rest, the office can step in and adjust so Mercer County property records stay fair for every owner.
Township assessors in Mercer County handle the hands-on work. They check new builds, review permits, and inspect properties to set values. The assessment date is January 1 each year. All real property in Mercer County gets assessed at 33 1/3 percent of fair market value, the same standard across most of Illinois. After township assessors finish their work, Mary McClellan's office reviews the results to make sure everything lines up. The Board of Review then hears complaints from owners who believe their assessed value is wrong or that a mistake was made. Farm property makes up a large share of Mercer County and gets assessed under a separate farmland formula tied to soil productivity rather than market sales.
The Mercer County Assessments page on the county website has contact details and general information about how the process works.
This is the starting point for anyone working with Mercer County property records or trying to reach the assessment office in Aledo.
| Office | Mercer County Supervisor of Assessments |
|---|---|
| Officer | Mary McClellan |
| Address | 100 SE 3rd Street, Aledo, IL 61231 |
| Phone | (309) 582-7814 (Option 7) |
| Fax | (309) 582-2541 |
| Website | mercercountyil.org |
Search Mercer County Property Records Online
Mercer County has an online property search through the DevNet Wedge platform at merceril.devnetwedge.com. You can look up parcels by address, owner name, or Property Index Number. The PIN is a code tied to the land itself, so it stays the same no matter who buys or sells the property. Most people start with an address search since that is what they know. Results show the assessed value, fair market value, lot size, and property class for each parcel in Mercer County. No login is needed and the tool is open to anyone.
The Mercer County property search portal at DevNet Wedge handles most online lookups for parcels in the county.
Type in an address, name, or PIN and the system shows full parcel data for any property in Mercer County.
Under 35 ILCS 200/, all property in Mercer County must be assessed at 33 1/3 percent of fair market value. The online search reflects that figure along with any exemptions applied to the parcel. You can also see which township the property sits in and the class code that tells you if it is farm, residential, or commercial. This is the fastest way to pull up Mercer County property records without a trip to Aledo. The search runs around the clock, so you can check records whenever it is convenient.
The statewide Illinois Property Tax Portal is another way to reach Mercer County records. Pick the county from the list and it links to the local tax inquiry system. Between these two tools, most searches for Mercer County property records can be done from home without a drive to the courthouse.
Mercer County Property Tax Records
Property taxes in Mercer County are paid in arrears. The bill you pay this year covers the prior year's assessment. Under 35 ILCS 200/, the lien date is January 1. That date sets who owns the parcel and what it is worth for tax purposes. Tax bills split the total owed among each taxing district that covers the parcel. Schools, the county, road districts, and local municipalities in Mercer County all get a share of the bill. The rate depends on where the parcel sits within the county.
A parcel in Aledo may carry a different total tax rate than farmland out in a rural township. That gap comes from the mix of taxing bodies that overlap each area. Knowing how those rates work helps when reading your Mercer County property records. The assessor sets the value. The County Treasurer collects the tax. If you have questions about how much you owe or when a payment is due, the Treasurer handles that side. For questions about the assessed value, Mary McClellan's office at 100 SE 3rd Street in Aledo is the right place to go.
Mercer County tax bills typically go out in the spring with two installment due dates later in the year. Missing a due date can lead to penalties and interest charges, so keep track of those dates.
Mercer County Property Exemptions
Property owners in Mercer County can apply for exemptions that reduce their tax bill. All forms go through the assessment office at 100 SE 3rd Street in Aledo. The General Homestead Exemption cuts $6,000 from your assessed value if you own and live in your home. No age limit applies. This is the most common exemption you will find in Mercer County property records.
Homeowners age 65 and up can also get the Senior Citizens Homestead Exemption for an extra $5,000 off. The Senior Citizens Assessment Freeze locks your assessed value so it does not climb each year, but income limits apply. A Disabled Persons Homestead Exemption gives a $2,000 cut under 35 ILCS 200/. Veterans with a service-connected disability may qualify for the Disabled Veterans Homestead Exemption, where the dollar amount depends on the VA rating. The Home Improvement Exemption defers increases from upgrades for up to four years. Once approved, an exemption shows up in your Mercer County property records and stays on file unless something changes.
- General Homestead Exemption: $6,000 reduction
- Senior Citizens Homestead Exemption: $5,000 (age 65+)
- Senior Citizens Assessment Freeze: locks value in place
- Disabled Persons Homestead Exemption: $2,000 reduction
- Disabled Veterans Homestead Exemption: varies by rating
- Home Improvement Exemption: defers increases up to 4 years
State Resources for Mercer County
The Illinois Department of Revenue property tax page provides guidance that applies to every county in the state, including Mercer. The department does not manage property tax directly. It sets rules and provides oversight while local offices handle the real work. You can find info about exemptions, assessment standards, and how to reach local offices on that page. Mercer County residents who need general help with how property tax works in Illinois can start there.
The County PIN Information page at the Department of Revenue helps you find your Property Index Number if you do not have it. Your PIN shows up on tax bills and assessment notices. It is the most reliable key for searching Mercer County property records. For state-level help, call 1-800-732-8866 or email REV.LOCALTAX@ILLINOIS.GOV.
Get Mercer County Records in Person
Walk into the assessment office at 100 SE 3rd Street in Aledo during regular hours. Bring the address or PIN of the property you want to check. Staff can look up the full record, print what you need, and answer questions about your assessment. No appointment is needed. Mercer County property records are public. Anyone can ask to see them.
Phone help works too. Call (309) 582-7814 and choose Option 7 for the assessment office. Staff can pull up basic data for you over the line. You can also fax requests to (309) 582-2541. For quick lookups, the online search at merceril.devnetwedge.com is faster than a trip to the courthouse. But if you need to file an exemption form, ask about an appeal, or deal with something that needs a signature, going in person to Aledo is the best choice. The Illinois Department of Revenue contact page can also point you in the right direction for Mercer County property records questions.
Nearby Counties
These counties border Mercer County. Property records belong to the county where the parcel is located. If a property sits near a county line, double check the address before you search the wrong system.