Overall
- Chicago-Naperville-Elgin
- 103.6
- Idaho Falls
- 94.4
Diff -9.2 RPP
Cost of living comparison based on BEA Regional Price Parities. Idaho Falls is 8.9% less expensive than Chicago-Naperville-Elgin.
Idaho Falls, ID is 8.9% less expensive than Chicago-Naperville-Elgin, IL-IN on BEA Regional Price Parities (overall RPP 94.4 vs 103.6). A $100,000 salary in Chicago-Naperville-Elgin buys about the same as $91,136 in Idaho Falls; the largest component gap is rents.
RPP parity plate
Pair IL:ID 103.6→94.4
TIER-GAP · CROSS-STATE · RENT-LED · BENCH-CROSS · 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.
What a salary in Chicago-Naperville-Elgin would need to be in Idaho Falls for the same purchasing power:
| In Chicago-Naperville-Elgin | In Idaho Falls | Difference |
|---|---|---|
| $50,000 | $45,568 | $-4,432 |
| $75,000 | $68,352 | $-6,648 |
| $100,000 | $91,136 | $-8,864 |
| $150,000 | $136,704 | $-13,296 |
Same BEA Regional Price Parity ratio as the table above (103.6 → 94.4), computed live from your number, nothing is sent anywhere.
Chicago-Naperville-Elgin, IL-IN and Idaho Falls, ID sit in clearly different price tiers, separated by 9.2 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 Idaho Falls is below it. That makes the move a change of price regime, not merely a rank swap.
Rents leads the difference, with Idaho Falls 28.0 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 $91,136 in Idaho Falls.
Diff -9.2 RPP
Diff -11.1 RPP
Diff -13.9 RPP
Diff -28.0 RPP
| Category | Chicago-Naperville-Elgin | Idaho Falls | Difference |
|---|---|---|---|
| Overall | 103.6 | 94.4 | -9.2 |
| Goods | 107.3 | 96.2 | -11.1 |
| Services | 83.6 | 69.7 | -13.9 |
| Rents | 112.0 | 84.0 | -28.0 |
Vertical line = national average (100)
Chicago-Naperville-Elgin and Idaho Falls share 17 published annual releases from 2008 through 2024. Their overall gap narrowed, moving from 10.2 to 9.2 RPP points. Chicago-Naperville-Elgin remained the higher-index metro in the latest release.
Rents changed the most within this pair: its gap moved 20.7 points between the first and latest shared releases (48.7 to 28.0 points). This describes a relative price-index history, not a forecast or a household budget.
| Release Year | Chicago-Naperville-Elgin RPP | Idaho Falls RPP | Relative Gap |
|---|---|---|---|
| 2008 | 105.4 | 95.2 | 10.2 points Chicago-Naperville-Elgin higher |
| 2012 | 105.1 | 93.2 | 11.9 points Chicago-Naperville-Elgin higher |
| 2016 | 103.8 | 95.4 | 8.4 points Chicago-Naperville-Elgin higher |
| 2020 | 104.5 | 90.9 | 13.5 points Chicago-Naperville-Elgin higher |
| 2024 | 103.6 | 94.4 | 9.2 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.
Idaho Falls is 8.9% less expensive than Chicago-Naperville-Elgin. The overall cost index is 94.4 vs 103.6 (national average = 100).
A $100,000 salary in Chicago-Naperville-Elgin has the same purchasing power as $91,136 in Idaho Falls. This is based on the BEA Regional Price Parity indexes.
Rents in Chicago-Naperville-Elgin are indexed at 112.0 while Idaho Falls is at 84.0 (national average = 100). Chicago-Naperville-Elgin has higher rents.
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.