West Chicago is one of Chicago’s 8 assessment townships to be reassessed this year. It has 25 residential assessment neighborhoods containing approximately 39,400 Class 2 multi-family properties.

This report contains detailed reporting about the West Chicago real estate market and a self-study of assessments produced at the modeling stage of assessments.


Assessor’s Summary

Chicago’s real estate market is robust.

Property values throughout the City have generally remained steady, or increased, since Chicago’s last reassessment in 2018. The median sale price of a multi-family property in West Chicago was about $210,000 in 2018 and $300,000 in 2020. This is a change of $90,000, or 43%. Note that each individual home’s 2021 assessment may go up or down by varying percentages, because every home is different.

In 2021, our job is to produce estimated values of all homes. At the initial stage of this job, our median estimated value of West Chicago multi-family properties was $270,000.

West Chicago 2021: Multi-Family Sale Prices & Estimated Values

2020 sale prices (homes that sold) Assessor’s Office’s 2021 estimated values (all homes)
Median $300,000 $270,000
Bottom and Top Third (33rd and 66th percentiles) $210,000 - $390,000 $210,000 - $500,000

Our model met 2 of 3 standards for high-quality assessment.

We tested our model’s estimated prices against actual sale prices using standards like those used by the International Association of Assessing Officers and Illinois Department of Revenue. In the 2021 reassessment of West Chicago the CCAO met 2 of 3 standards for high-quality assessment.

Increases in property values don’t necessarily cause the same increases in tax bills.

The Assessor does not set property tax levies, rates, or bills. But your property’s share of the total assessed value of all Chicago properties affects its share of Chicago’s property taxes. Your property’s share will depend on 2021 reassessments throughout Chicago, from homes in Chatham and Jefferson Park to commercial properties in Little Village and the Loop.

This means your home’s value can increase, while its share of property taxes could increase, decrease, or stay the same due to Chicago’s reassessment. If other properties’ assessments increase more than yours, this can shrink your home’s share of property taxes.

The 2021 reassessment will affect the property tax bill issued in the summer of 2022. Your property tax bills also list the taxing districts funded by your property taxes.


Market Report

The Assessor’s Office used 7 years of sales throughout Chicago, from 2013 through the end of 2020, to estimate home values in 2021. Below, we show data about these real estate market changes in West Chicago.

Median Sale Prices

Below we show year-over-year sale prices of homes in West Chicago. The median sale price is shown in dark green, with the light green band showing the bottom and top thirds of the market.

In 2020 – the most recent full year of data we can access – the median sale price of a West Chicago multi-family property was about $300,000, with the lower third of sale prices around $210,000 and the top third around $390,000.

Sale volume

In 2020, there were 1,122 sales of multi-family homes in West Chicago.

2020 Sale Prices

Here’s how sale prices in 2020 varied throughout West Chicago.

You can read more about sales in West Chicago, find neighborhood-level information, and read more about how COVID-19 affected the real estate market in the Appendix at the end of this report.

Note that these are average sales trends in West Chicago. To calculate assessments, we use price and characteristics data for 7 years of sales throughout Chicago. More details about this are in the next section.

Fun facts

  • The top sale price for a multi-family property in West Chicago in 2020 was $3,109,000.

  • Of all the single-family homes that sold in West Chicago in 2020, the average property was 1,682 square feet, 74 years old, and had 3 bedrooms and 2 bathrooms.

  • Of all the Class 2 multi-family homes that sold in West Chicago in 2020, the average property was 2,810 square feet, 111 years old, and had 5 bedrooms and 2.5 bathrooms.


Model & Results

How does the model know what my home is worth?

“The model” is a computerized statistical model that uses real estate market data to estimate the value of homes that haven’t sold. These models are often called Automated Valuation Models, and are the standard for conducting computer-assisted mass appraisal.

The goal of the model is to answer this question: “What would the sale price of every home be if it had sold recently in an arms-length transaction?”

To answer this question, we use a two-step process:

  1. Modeling. First, we use computer code to analyze data about home sales. Any two homes may have different characteristics (location, number of bedrooms, etc.) and sale prices. But there are consistent patterns in how characteristics affect sale prices on average. It’s important to detect these patterns accurately. To do that, we use computer code to train a predictive machine learning model, which learns to recognize complex patterns much faster than a human could. The output of this step is a model which can be used to predict any home’s sale price based on its characteristics and these learned patterns.

  2. Valuation. We then use the model created in Step 1 to predict values for all residential properties. These predicted values are the scope of this report, but these values are subject to change. Estimated values produced by the model are reviewed by software and by our expert analysts, who review assessed value changes by neighborhood and property class and make adjustments as necessary.

  3. Mailing. Finally, we mail Reassessment Notices to homeowners with their property’s estimated market value, its characteristics, and its assessed value.

For the 2021 reassessment of the City of Chicago, we used around 504,000 sales from the last 7 years to train the model. We leveraged over two dozen characteristics for each home so that our model could detect all related patterns between characteristics and sale price, and so that our estimated home values were as accurate as possible. We used a variety of location characteristics (like school district, whether a property is close to a road, and assessor neighborhood code) and others (like flood risk and median income of the surrounding area).

You can learn more about our modeling process here:

  • Read: How the model works to produce the most accurate, uniform, non-regressive assessments we can with our current data
  • Watch: Our presentation at Chi Hack night on an earlier version of the model
  • FAQs: about the model

Model Performance: Estimated Market Values

The job of the Assessor’s Office is to estimate market values of all homes, such that estimates are an accurate and unbiased reflection of the market.

The map below shows averages of our model’s estimated 2021 values of all homes throughout West Chicago Township:

Fun facts: all homes

  • Of all the 25,886 single-family homes in West Chicago, the average property was 1,514 square feet, 89 years old, and had 3 bedrooms and 1.5 bathrooms.

  • Of all the 39,491 Class 2 multi-family homes in West Chicago, the average property was 2,900 square feet, 114 years old, and had 5 bedrooms and 2.5 bathrooms.


Average increases in estimated values

The map below shows how values for multi-family properties have changed, on average, from last year’s final values to this year’s 2021 model values.

Note that:

  • Every individual property might have experienced a different increase or decrease in estimated value.

  • Individual values are subject to change after modeling before they are mailed to taxpayers, during analyst review.

  • Increases in assessments don’t necessarily cause increases in tax bills (see the next section).