Cook County · South & West suburbs

Lemont Township Property Tax Appeal — 2026 Deadlines & Filing Windows

Everything a Lemont homeowner needs to appeal an over-assessment this year: the current filing window, where you sit in the reassessment cycle, how over-assessed Lemont homes are, and a plain walkthrough to file your own appeal — free, keeping every dollar you save.

Lemont Township’s 2026 Assessor appeal window opens later this year, and because 2026 is Lemont’s triennial reassessment year, it is the most important year in three to check. By ChonkHub’s read of the public roll, about 10.6% of Lemont’s 6,796 assessable homes and condos are assessed above comparable local properties, a median of $2,019 a year in likely over-assessment. Historically, 17.3% of Lemont residential appeals to the Assessor have won a reduction, and the Board of Review is a free second chance after that.

When is the property tax appeal deadline in Lemont Township?

Lemont Township’s 2026 appeal window with the Cook County Assessor has not been published yet. Cook opens each township on a rolling schedule through the year; the exact deadline appears on your Reassessment Notice and on the Assessor’s calendar. Check back or confirm directly with the Assessor.

Source: Cook County Assessor Assessment & Appeal Calendar, as of 25 June 2026. Confirm on cookcountyassessoril.gov →

Is Lemont Township being reassessed in 2026?

Lemont Township is in the Assessor’s South & West suburbs reassessment group, which Cook County reassesses once every three years. 2026 is its reassessment year — the year your assessed value is most likely to change, and the most important year to check, because a new over-assessment can lock in for three years.

What towns are in Lemont Township?

Lemont Township covers Lemont in Cook County — Lemont is the largest share, about 99% of its homes. Your township is determined by where the property sits, not your mailing address, and it sets your filing deadline: homeowners across these towns file on the same 2026 Lemont schedule.

How over-assessed are homes in Lemont Township?

By ChonkHub’s read of the public roll, about 10.6% of 6,796 assessable dwellings in Lemont Township are assessed materially higher than comparable local properties, a median of $2,019 a year in likely over-assessment. It is a population estimate — whether your specific home is over-assessed is a per-parcel question the address check answers directly.

Across Cook County, roughly 124,411 dwellings are strongly over-assessed. See the full over-assessment report and method →

What are the odds of a successful Lemont Township appeal?

In Lemont Township, about 17.3% of residential appeals to the Assessor have historically won a reduction — and the Board of Review, a separate second stage, reduces assessments again for many who get little from the Assessor.

Lemont Township — appeal outcomes at the Assessor

Countywide, the Assessor reduces about 25.0% of appeals and the Board of Review about 31.9%. Full outcome data by year →

How do I appeal my property taxes in Lemont Township?

You appeal in up to two free stages — first the Cook County Assessor, then, if needed, the Board of Review — filing as the property owner with comparable properties as your evidence. In Lemont Township, start before your window opens: confirm you are over-assessed, gather comparables, and file on the county’s free portal.

Read the full step-by-step guide → · Common questions →