Overall
Diff -0.7 RPP
Cost of living comparison based on BEA Regional Price Parities. Helena is 0.7% less expensive than Kankakee.
Helena, MT is 0.7% less expensive than Kankakee, IL on BEA Regional Price Parities (overall RPP 95.7 vs 96.4). A $100,000 salary in Kankakee buys about the same as $99,254 in Helena; the largest component gap is services.
RPP parity plate
Pair IL:MT 96.4→95.7
PHOTO-FINISH · CROSS-STATE · SPLIT-BUDGET · BOTH-BELOW · PP-PAR
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.
Kankakee, IL and Helena, MT are a photo finish on overall price level, only 0.7 RPP points apart. A salary conversion is therefore a fine adjustment, not evidence of a fundamentally different cost regime.
Services creates the largest separation: Helena is 16.8 points lower. But goods move against the overall direction, so this is a split budget rather than a clean across-the-board winner.
Comparable population context is incomplete for this pair, so no market-scale explanation is inferred from the price indexes.
Both metros remain below the U.S. benchmark of 100. This comparison chooses between two below-average price levels; “more expensive” here does not mean nationally expensive.
For a service-heavy household, test childcare, health, and other locally supplied costs before relying on rent alone. The BEA ratio converts $100,000 in Kankakee to $99,254 in Helena, but it is not a personal spending weight.
Diff -0.7 RPP
Diff +2.4 RPP
Diff -16.8 RPP
Diff -2.7 RPP
| Category | Kankakee | Helena | Difference |
|---|---|---|---|
| Overall | 96.4 | 95.7 | -0.7 |
| Goods | 93.6 | 96.0 | +2.4 |
| Services | 89.4 | 72.6 | -16.8 |
| Rents | 92.9 | 90.1 | -2.7 |
Vertical line = national average (100)
What a salary in Kankakee would need to be in Helena for the same purchasing power:
| In Kankakee | In Helena | Difference |
|---|---|---|
| $50,000 | $49,627 | $-373 |
| $75,000 | $74,441 | $-559 |
| $100,000 | $99,254 | $-746 |
| $150,000 | $148,881 | $-1,119 |
Same BEA Regional Price Parity ratio as the table above (96.4 → 95.7), computed live from your number, nothing is sent anywhere.
Helena is 0.7% less expensive than Kankakee. The overall cost index is 95.7 vs 96.4 (national average = 100).
A $100,000 salary in Kankakee has the same purchasing power as $99,254 in Helena. This is based on the BEA Regional Price Parity indexes.
Rents in Kankakee are indexed at 92.9 while Helena is at 90.1 (national average = 100). Kankakee 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.