If you are an Illinois student trying to understand where your ACT score stands, here is the full picture: the average ACT score for Illinois high school juniors in 2025 was 18.8 on the composite. That is below the national average of 19.4 and significantly below what most four-year colleges in Illinois expect from applicants.

Understanding the difference between the state average and what competitive Illinois colleges actually require is the most important thing you can do before you start setting your score target.

Illinois ACT Score Overview at a Glance

Why Illinois State Average Scores Look Lower Than You Expect

Illinois requires all high school juniors to take the ACT as part of its state accountability mandate. That mandatory participation is the most important context for reading the 18.8 state average correctly.

When every student in the state takes the test, including students who have no plans to attend a four-year college, the average composite score drops. It does not reflect the scores of students who are actively preparing for college admission. It reflects the entire junior class across every school, every district, and every preparation level in Illinois.

Illinois switched from the ACT to the SAT in 2017 and used the SAT through 2024, when it returned to the ACT. The last time Illinois juniors were required to take the ACT in 2016, they posted average scores between 20 and 21.

The practical takeaway is this: if you are a college-bound Illinois student actively preparing for the ACT, the 18.8 state average is not your competition. The average ACT score at Illinois four-year colleges, which is 25, is a far more relevant benchmark for your preparation goals.

What Is a Good ACT Score for Illinois Students?

The answer depends entirely on which Illinois schools you are targeting. Here is how to read your score against what different tiers of Illinois colleges actually expect.

Score of 18 or below: You are at or below the state average. For most four-year Illinois colleges this score falls below the competitive range. Focused preparation before applying is strongly recommended.

Score of 19 to 21: You are near or at the college-ready benchmark set by the Illinois Report Card. This range is sufficient for community colleges and some four-year institutions with open or broad admissions policies.

Score of 22 to 26: You are competitive for a solid range of Illinois four-year colleges. The average ACT score across Illinois colleges is 25, which means this range puts you in a competitive position at most schools in the state.

Score of 27 to 30: You are above average for Illinois colleges and competitive for more selective in-state universities including University of Illinois Urbana-Champaign, where the average ACT score is around 32 and the 25th percentile is 29.

Score of 31 and above: You are in a strong position for the most selective Illinois colleges. The University of Chicago has an average ACT score of 35, making it among the most competitive schools in the country regardless of state.

ACT Score Requirements at Top Illinois Colleges

Here is how the ACT score landscape looks across a range of Illinois colleges:

The average ACT score across all Illinois four-year colleges is 25. If you are targeting schools in the middle of this list, a score between 24 and 27 puts you in a solid position. If you are targeting UIUC or more selective schools, a score of 29 or above is where you want to be.

Illinois ACT Scores Compared to the National Average

The average Illinois ACT score was 18.1 on English Language Arts and 18.8 on math in 2025, which according to an ACT conversion tool is about a 970 on the SAT. Nationally, the average ACT composite score was 19.4.

Illinois scores below the national average for one primary reason: mandatory participation. In a state where the ACT is mandated for all high school juniors, overall scores are lower since everyone takes the test. In states where students only take the ACT to use scores in college applications, averages are higher because those students are self-selected and actively preparing.

This distinction matters for how you interpret your own score. Scoring a 21 in Illinois puts you above the state average and at the college-ready benchmark. Scoring a 25 puts you above the average admitted student at most Illinois colleges. Neither of those is the same as being competitive at the most selective schools in the state.

What Illinois ACT Score Do You Actually Need?

The right target depends on your specific school list. Here is a practical framework:

Targeting community college or open admissions schools: A score of 18 to 20 meets most requirements. Preparation is still worthwhile for scholarship eligibility.

Targeting mid-range Illinois four-year colleges: Aim for 23 to 26. This puts you within or above the average for schools like DePaul, Loyola, and Illinois State.

Targeting University of Illinois Urbana-Champaign: Aim for 29 or above. The 25th percentile at UIUC is 29, meaning a score below that puts you in a difficult position for admission.

Targeting Northwestern or University of Chicago: Aim for 33 or above. Both schools are among the most selective in the country and expect ACT scores in the top 1% to 2% nationally.

How to Improve Your Illinois ACT Score

Whether your target is a 21 for college readiness or a 32 for UIUC, the path to improvement is the same: targeted preparation built around the specific sections and question types that are costing you the most points.

The students who improve their ACT scores consistently share the same approach:

• They started with a diagnostic baseline that showed them exactly which sections and question types were costing them points
• They focused preparation on their weakest areas rather than reviewing material they already knew
• They practiced with full timed tests to build the pacing habits that prevent avoidable errors under pressure
• They reviewed every mistake before moving on and used that analysis to drive the next session
• They tracked progress over time so improvement was measurable, not assumed

Illinois gives you an advantage that students in other states do not have: mandatory ACT testing in junior year creates a real baseline score and leaves time for preparation and retakes before college applications are due. Use that window.

How ScoreSmart Can Help Illinois Students Hit Their Target

If your ACT score is not where it needs to be for your target Illinois colleges, ScoreSmart’s ACT test prep is built around exactly the kind of preparation that moves scores across meaningful thresholds. Rather than giving you a generic curriculum, ScoreSmart shows you precisely which sections and question types are costing you points and builds your preparation around closing those specific gaps.

If you are also considering the SAT as an alternative or additional path, ScoreSmart’s SAT test prep applies the same performance analytics framework to the SAT, giving you a clear picture of where your score stands and what to fix.

Whether your goal is to improve your ACT score from 20 to 25 for a mid-range Illinois college or push to 29 or above for UIUC, or to improve your SAT score as part of a parallel strategy, ScoreSmart gives you the data to prepare smarter, not just harder.

Your Illinois college list is reachable. The question is whether your preparation is built to get you there.

The Bottom Line

Here is what every Illinois student needs to know about the average ACT score for Illinois:

• The Illinois state average ACT composite is 18.8 for the class of 2025, below the national average of 19.4
• The lower state average reflects mandatory participation across all juniors, not the scores of college-bound students specifically
• The college-ready ACT benchmark in Illinois is 21 or above
• The average ACT score across Illinois four-year colleges is 25
• UIUC has a 25th percentile of 29 and an average of 32, making it one of the most ACT-competitive public universities in the state
• University of Chicago and Northwestern require scores in the 33 to 35 range to be competitive
• Illinois students have a built-in advantage with mandatory junior-year testing that creates a baseline and time for targeted retakes before applications are due

Know your target school’s average. Build your preparation around the gap between your current score and that number. That is the formula that moves Illinois students from the state average to the college they are aiming for.