Overall
- Billings
- 93.5
- Chicago-Naperville-Elgin
- 103.6
Diff +10.1 RPP
Billings vs Chicago-Naperville-Elgin
Cost of living comparison based on BEA Regional Price Parities. Chicago-Naperville-Elgin is 10.8% more expensive than Billings.
10.8% more expensive
Chicago-Naperville-Elgin, IL-IN is 10.8% more expensive than Billings, MT on BEA Regional Price Parities (overall RPP 103.6 vs 93.5). A $100,000 salary in Billings buys about the same as $110,766 in Chicago-Naperville-Elgin; the largest component gap is rents.
- Overall RPP 93.5 (Billings) vs 103.6 (Chicago-Naperville-Elgin)
- $100k in Billings ≈ $110,766 purchasing power in Chicago-Naperville-Elgin
- Rents drives the gap (+34.6 RPP points)
RPP parity plate
Pair MT:IL 93.5→103.6
TIER-GAP · CROSS-STATE · RENT-LED · BENCH-CROSS · PP-SHIFT
- TIER-GAP Clear tier gap
- CROSS-STATE MT × IL
- 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 Billings would need to be in Chicago-Naperville-Elgin for the same purchasing power:
| In Billings | In Chicago-Naperville-Elgin | Difference |
|---|---|---|
| $50,000 | $55,383 | +$5,383 |
| $75,000 | $83,074 | +$8,074 |
| $100,000 | $110,766 | +$10,766 |
| $150,000 | $166,149 | +$16,149 |
$ in Billings = in Chicago-Naperville-Elgin
Same BEA Regional Price Parity ratio as the table above (93.5 → 103.6), computed live from your number, nothing is sent anywhere.
What This Comparison Actually Tells You
Billings, MT and Chicago-Naperville-Elgin, IL-IN sit in clearly different price tiers, separated by 10.1 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 Billings is below it. That makes the move a change of price regime, not merely a rank swap.
Rents leads the difference, with Chicago-Naperville-Elgin 34.6 points higher than Billings. 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 Billings corresponds to $110,766 in Chicago-Naperville-Elgin.
Category Breakdown
Goods
- Billings
- 96.0
- Chicago-Naperville-Elgin
- 107.3
Diff +11.3 RPP
Services
- Billings
- 72.4
Diff +11.1 RPP
Rents
- Billings
- 77.4
- Chicago-Naperville-Elgin
- 112.0
Diff +34.6 RPP
| Category | Billings | Chicago-Naperville-Elgin | Difference |
|---|---|---|---|
| Overall | 93.5 | 103.6 | +10.1 |
| Goods | 96.0 | 107.3 | +11.3 |
| Services | 72.4 | 83.6 | +11.1 |
| Rents | 77.4 | 112.0 | +34.6 |
Visual Comparison
Overall
Billings 93.5
Chicago-Naperville-Elgin 103.6
Goods
Billings 96.0
Chicago-Naperville-Elgin 107.3
Services
Billings 72.4
Chicago-Naperville-Elgin 83.6
Rents
Billings 77.4
Chicago-Naperville-Elgin 112.0
Vertical line = national average (100)
Billings
93.5
Cost Index
Chicago-Naperville-Elgin
103.6
Cost Index
How the Price Gap Changed
Billings and Chicago-Naperville-Elgin share 17 published annual releases from 2008 through 2024. Their overall gap held broadly steady, moving from 10.5 to 10.1 RPP points. Chicago-Naperville-Elgin remained the higher-index metro in the latest release.
Rents changed the most within this pair: its gap moved 6.8 points between the first and latest shared releases (41.4 to 34.6 points). This describes a relative price-index history, not a forecast or a household budget.
| Release Year | Billings RPP | Chicago-Naperville-Elgin RPP | Relative Gap |
|---|---|---|---|
| 2008 | 95.0 | 105.4 | 10.5 points Chicago-Naperville-Elgin higher |
| 2012 | 98.0 | 105.1 | 7.2 points Chicago-Naperville-Elgin higher |
| 2016 | 94.8 | 103.8 | 9.0 points Chicago-Naperville-Elgin higher |
| 2020 | 92.2 | 104.5 | 12.3 points Chicago-Naperville-Elgin higher |
| 2024 | 93.5 | 103.6 | 10.1 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 Chicago-Naperville-Elgin more expensive than Billings?
Chicago-Naperville-Elgin is 10.8% more expensive than Billings. The overall cost index is 103.6 vs 93.5 (national average = 100).
What salary in Chicago-Naperville-Elgin equals $100K in Billings?
A $100,000 salary in Billings has the same purchasing power as $110,766 in Chicago-Naperville-Elgin. This is based on the BEA Regional Price Parity indexes.
How do rents compare between Billings and Chicago-Naperville-Elgin?
Rents in Billings are indexed at 77.4 while Chicago-Naperville-Elgin is at 112.0 (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.