What the county's own roll says, and how many parcels sit above their neighbours.
186,478parcels on record
2,440with a published assessment
$88,083median assessed value
366above their neighbourhood median
Among those, the typical excess is $5,238 of
assessed value above the median for like-classified land in the same town — $1,917,036
in total across Kane County.
A median has half of everything above it by definition, boards do not grant every
uniformity claim, and being above a median is a ground to argue rather than proof of error. These
are assessed values, not tax bills.
Your deadline in Kane County
30 days from the publication of your township's assessment roll in the local newspaper. The window is short and it is not the same date across the county.
Statutory basis: 35 ILCS 200/16-55.
A late filing cannot be cured, so confirm the date on your own notice — it is not the same across the county.
How the assessment was calculated
Illinois assesses at 33.33% of market value.
The assessor estimates market value by mass appraisal — a model over recent sales, adjusted by the
characteristics they hold on file for your property. If those characteristics are wrong, the number
is wrong. The full anatomy is here.
The argument most people miss
Beyond “my house is worth less than they say”, the Illinois Constitution requires uniform
taxation. If comparable property near you is assessed at a lower rate per square foot, that is a
ground for relief in its own right — no appraisal needed, and built from figures the assessor
published themselves.