The 10 Dumbest Places In Illinois For 2026

The unfortunate fact of the matter is that some places in the Prairie State have a larger percent of their population that never graduated from high school.

While the emphasis on going to college might be overblown, the fact is that not graduating from high school puts you at a significant disadvantage on average. Educational attainment might not be the best way to measure one person’s intelligence, but it does shine a light on the state.

We will use Saturday Night Science to determine what places in Illinois have the highest percentage of adults without a high school degree.

A recent study we published found that Illinois is the 31st smartest state in the United States, with an average IQ of 99.

But that doesn’t mean that a few cities in Illinois are a bit slower than others due to a lack of basic education.

Table Of Contents: Top Ten | Methodology | Summary | Table

Don’t freak out.

Some places are just smarter than others, but that says nothing about the character of the people living there. It’s another data point a real estate agent would never tell you.

For this ranking, we only looked at cities with populations greater than 5,000, leaving us 323 cities in Illinois to rank. You can take a look at the data below.

For more Illinois reading, check out:

• Best Places To Live In Illinois
• Safest Places To Live In Illinois

Methodology: How we determined the dumbest cities in the Prairie State

We realize that formal education is only part of it when it comes to being intelligent, but on the other hand, knowing the difference between they’re, their, and there is always going to make you look pretty stupid.

So, we used Saturday Night Science to narrow down our criteria to focus on a city’s educational opportunities and what percentage of the population takes advantage of those opportunities.

In short, we came up with these criteria to determine the dumbest cities in Illinois:

• % of the city’s population with less than a high school education (Age 25+)
• % of city’s population with a college degree (Age 25+)

We got the data from the U.S. Census 2020-2024 American Community Survey.

Then, our algorithm generates a rank for each place in these categories. After crunching all the numbers, a ranking of the cities in Illinois from dumbest to brightest.

For this ranking, we used every Illinois city with at least 5,000 residents. We updated this article for 2026, and it’s our eleventh time ranking the dumbest cities in Illinois.

There You Have It – Now That You’re Asleep

If you’re measuring the locations in Illinois where there are a high number of dropouts and adults who never received a formal education, this is an accurate ranking.

The dumbest cities in Illinois are Cicero, Chester, Pinckneyville, Harvey, Summit, Northlake, Posen, Round Lake Beach, Belvidere, and Burbank.

If you’re also curious enough, here are the smartest places in Illinois, according to science:

1. Western Springs
2. Glencoe
3. Winnetka

For more Illinois reading, check out:

• Best Places To Live In Illinois
• Cheapest Places To Live In Illinois
• Most Dangerous Cities In Illinois
• Richest Cities In Illinois
• Safest Places In Illinois
• Worst Places To Live In Illinois
• Most Expensive Places To Live In Illinois

Dumbest Cities In Illinois For 2026