What does a Data Scientist salary really buy you in Illinois?
Illinois is near the US average cost of livingData: BLS OEWS 2024 + BEA Regional Price Parities 2022 • Updated 2026-03-31
Illinois's Regional Price Parity (RPP) is 101.3, meaning prices are 1.3% higher the national average. A Data Scientist earning $113,490 in Illinois has the equivalent purchasing power of $112,033 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) | $65,420 | $64,580 | $-839 |
| 25th Percentile (P25) | $82,010 | $80,957 | $-1,052 |
| Median (P50) | $113,490 | $112,033 | $-1,456 |
| 75th Percentile (P75) | $147,130 | $145,241 | $-1,888 |
| 90th Percentile (P90) | $172,220 | $170,009 | $-2,210 |
Illinois's cost of living is close to the national average, so $113,490 keeps most of its value at $112,033 in real terms. Location choice here is more about career opportunities than cost arbitrage.
Where does Data Scientist salary stretch the furthest? Top 10 states ranked by COL-adjusted median salary.
Illinois ranks #18 out of 49 states for Data Scientist after cost-of-living adjustment.
Some links are affiliate links. See our disclosure.
A Data Scientist in Illinois earns a median salary of $113,490 per year. After adjusting for Illinois's cost of living (RPP=101.3), the real purchasing power is $112,033 — 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 Data Scientist in Illinois: $113,490 x (100 / 101.3) = $112,033. This represents what the salary would be worth in a state with average living costs.