Overall
- Chicago-Naperville-Elgin
- 103.6
- St. Louis
- 95.1
Diff -8.5 RPP
Chicago-Naperville-Elgin vs St. Louis
Cost of living comparison based on BEA Regional Price Parities. St. Louis is 8.2% less expensive than Chicago-Naperville-Elgin.
8.2% less expensive
St. Louis, MO-IL is 8.2% less expensive than Chicago-Naperville-Elgin, IL-IN on BEA Regional Price Parities (overall RPP 95.1 vs 103.6). A $100,000 salary in Chicago-Naperville-Elgin buys about the same as $91,788 in St. Louis; the largest component gap is rents.
- Overall RPP 103.6 (Chicago-Naperville-Elgin) vs 95.1 (St. Louis)
- $100k in Chicago-Naperville-Elgin ≈ $91,788 purchasing power in St. Louis
- Rents drives the gap (-33.0 RPP points)
RPP parity plate
Pair IL:MO 103.6→95.1
TIER-GAP · CROSS-STATE · RENT-LED · BENCH-CROSS · PP-SHIFT
- TIER-GAP Clear tier gap
- CROSS-STATE IL × MO
- RENT-LED Rent-led gap
- BENCH-CROSS Benchmark cross
- PP-SHIFT PP shift
Instrument codes from this pair's BEA Regional Price Parities (overall · goods · services · rents · national benchmark 100 · purchasing-power conversion), not a ranking or recommendation.
Salary Equivalents
What a salary in Chicago-Naperville-Elgin would need to be in St. Louis for the same purchasing power:
| In Chicago-Naperville-Elgin | In St. Louis | Difference |
|---|---|---|
| $50,000 | $45,894 | $-4,106 |
| $75,000 | $68,841 | $-6,159 |
| $100,000 | $91,788 | $-8,212 |
| $150,000 | $137,682 | $-12,318 |
$ in Chicago-Naperville-Elgin = in St. Louis
Same BEA Regional Price Parity ratio as the table above (103.6 → 95.1), computed live from your number, nothing is sent anywhere.
What This Comparison Actually Tells You
Chicago-Naperville-Elgin, IL-IN and St. Louis, MO-IL sit in clearly different price tiers, separated by 8.5 RPP points. At this distance, treating the same nominal salary as equivalent would materially change purchasing power.
This route crosses the national benchmark: Chicago-Naperville-Elgin is above 100 while St. Louis is below it. That makes the move a change of price regime, not merely a rank swap.
Rents leads the difference, with St. Louis 33.0 points lower than Chicago-Naperville-Elgin. Goods, services, and rents all point in the same broad direction, making the headline comparison more transferable across household types.
Comparable population context is incomplete for this pair, so no market-scale explanation is inferred from the price indexes.
For a housing-sensitive move, validate the rent gap first: HUD Fair Market Rent and the actual unit size can overturn what the blended index implies. On the BEA ratio alone, $100,000 in Chicago-Naperville-Elgin corresponds to $91,788 in St. Louis.
Category Breakdown
Goods
- Chicago-Naperville-Elgin
- 107.3
- St. Louis
- 100.0
Diff -7.3 RPP
Services
- St. Louis
- 69.9
Diff -13.7 RPP
Rents
- Chicago-Naperville-Elgin
- 112.0
- St. Louis
- 79.0
Diff -33.0 RPP
| Category | Chicago-Naperville-Elgin | St. Louis | Difference |
|---|---|---|---|
| Overall | 103.6 | 95.1 | -8.5 |
| Goods | 107.3 | 100.0 | -7.3 |
| Services | 83.6 | 69.9 | -13.7 |
| Rents | 112.0 | 79.0 | -33.0 |
Visual Comparison
Overall
Chicago-Naperville-Elgin 103.6
St. Louis 95.1
Goods
Chicago-Naperville-Elgin 107.3
St. Louis 100.0
Services
Chicago-Naperville-Elgin 83.6
St. Louis 69.9
Rents
Chicago-Naperville-Elgin 112.0
St. Louis 79.0
Vertical line = national average (100)
Chicago-Naperville-Elgin
103.6
Cost Index
St. Louis
95.1
Cost Index
How the Price Gap Changed
Chicago-Naperville-Elgin and St. Louis share 17 published annual releases from 2008 through 2024. Their overall gap narrowed, moving from 14.4 to 8.5 RPP points. Chicago-Naperville-Elgin remained the higher-index metro in the latest release.
Goods changed the most within this pair: its gap moved 8.4 points between the first and latest shared releases (15.7 to 7.3 points). This describes a relative price-index history, not a forecast or a household budget.
| Release Year | Chicago-Naperville-Elgin RPP | St. Louis RPP | Relative Gap |
|---|---|---|---|
| 2008 | 105.4 | 91.0 | 14.4 points Chicago-Naperville-Elgin higher |
| 2012 | 105.1 | 94.5 | 10.6 points Chicago-Naperville-Elgin higher |
| 2016 | 103.8 | 94.5 | 9.3 points Chicago-Naperville-Elgin higher |
| 2020 | 104.5 | 95.2 | 9.3 points Chicago-Naperville-Elgin higher |
| 2024 | 103.6 | 95.1 | 8.5 points Chicago-Naperville-Elgin higher |
Annual BEA Regional Price Parity releases; a higher index means a higher price level relative to the national average of 100. Selected years shown from the full shared series.
Frequently Asked Questions
Is St. Louis more expensive than Chicago-Naperville-Elgin?
St. Louis is 8.2% less expensive than Chicago-Naperville-Elgin. The overall cost index is 95.1 vs 103.6 (national average = 100).
What salary in St. Louis equals $100K in Chicago-Naperville-Elgin?
A $100,000 salary in Chicago-Naperville-Elgin has the same purchasing power as $91,788 in St. Louis. This is based on the BEA Regional Price Parity indexes.
How do rents compare between Chicago-Naperville-Elgin and St. Louis?
Rents in Chicago-Naperville-Elgin are indexed at 112.0 while St. Louis is at 79.0 (national average = 100). Chicago-Naperville-Elgin has higher rents.
Data sources
- BEA Regional Price Parities (RPP), the cost-of-living indices shown on this page
- U.S. Census Bureau, American Community Survey (ACS), gross-rent observations behind the rents component
- BLS Consumer Price Index (CPI), goods and services price relatives
- BLS Occupational Employment and Wage Statistics (OEWS), labor-driven services component
- HUD Fair Market Rents (FMR), 40th-percentile rent cross-reference
Every figure on PlainCost is rendered directly from BEA Regional Price Parity source data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, our changelog, or report a data error. Data current as of 2026-08-11. Rankings measure the published cost-of-living index only; we don't recommend where to live or rate any metro's quality of life.