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What does a Biological Science Teachers, Postsecondary salary really buy you in Illinois?
Illinois is near the US average cost of livingData: BLS OEWS 2025 + BEA Regional Price Parities 2022 • Updated 2026-05-19
Illinois's Regional Price Parity (RPP) is 101.3, meaning prices are 1.3% higher the national average. A Biological Science Teachers, Postsecondary earning $99,060 in Illinois has the equivalent purchasing power of $97,788 in an average-cost US state.
Every dollar goes further in low-cost states. Here is how each salary percentile compares after adjusting for Illinois's cost of living.
| Percentile | Nominal Salary | COL-Adjusted | Difference |
|---|---|---|---|
| 10th Percentile (P10) | $47,340 | $46,732 | $-607 |
| 25th Percentile (P25) | $62,740 | $61,934 | $-805 |
| Median (P50) | $99,060 | $97,788 | $-1,271 |
| 75th Percentile (P75) | $132,780 | $131,076 | $-1,703 |
| 90th Percentile (P90) | $207,930 | $205,261 | $-2,668 |
Illinois's cost of living is close to the national average, so $99,060 keeps most of its value at $97,788 in real terms. Location choice here is more about career opportunities than cost arbitrage.
With an RPP of 101.3, Illinois is within a few percent of the national cost-of-living baseline. Salary adjustment for Biological Science Teachers, Postsecondary is therefore minor — what you earn is close to what you'd keep in real purchasing power.
After adjusting for Illinois's cost of living, $99,060 nominal nets out to $97,789 in real purchasing power — a small 1.3% loss. The state's cost profile is close enough to average that COL alone shouldn't drive location decisions for this Biological Science Teachers, Postsecondary.
Ranked on COL-adjusted median pay for Biological Science Teachers, Postsecondary, Illinois places #8 of 49 states — top quartile. Either nominal wages run high, cost of living runs low, or both.
Where does Biological Science Teachers, Postsecondary salary stretch the furthest? Top 10 states ranked by COL-adjusted median salary.
Illinois ranks #8 out of 49 states for Biological Science Teachers, Postsecondary after cost-of-living adjustment.
How much do you actually take home? See Biological Science Teachers, Postsecondary take-home pay in Illinois after taxes →
A Biological Science Teachers, Postsecondary in Illinois earns a median salary of $99,060 per year. After adjusting for Illinois's cost of living (RPP=101.3), the real purchasing power is $97,788 — a -1.3% difference.
Illinois's cost of living is 1.3% higher than the national average according to the BEA Regional Price Parities (2022). The RPP index for Illinois is 101.3 (US average = 100).
Regional Price Parities (RPPs) are price indexes published by the U.S. Bureau of Economic Analysis (BEA) that measure differences in price levels across states. They are expressed as a percentage of the national average (US = 100). Higher RPP means higher cost of living.
The adjusted salary is calculated as: Nominal Salary x (100 / RPP). For a Biological Science Teachers, Postsecondary in Illinois: $99,060 x (100 / 101.3) = $97,788. This represents what the salary would be worth in a state with average living costs.
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