Median rent is 32% lower in Rockford ($985/mo vs $1,446/mo). Buying is cheaper in Rockford, where the median home runs $129,000 versus $484,800. Households earn more in Boise City ($83,904 vs $54,752 a year). Taken together, Boise City is the more affordable choice with a cost index of 89.4 against 90.2 — about 1% lower overall prices. After adjusting income for local prices, a typical paycheck stretches further in Boise City, ID.
Cost of living verdict
Boise City is 1% cheaper overall
Cost of Living Index: 89.4 in Boise City vs 90.2 in Rockford (US national average = 100)
City A
Boise City, ID
City B
Rockford, IL
How much would you need to earn in Rockford, IL to maintain your standard of living from Boise City, ID?
Equivalent salary in Rockford, IL
$75,682
You'd need $682 more (1% higher).
Based on BEA Regional Price Parity (cost index) for each metro area. This estimates overall purchasing power; it does not account for taxes or take-home pay differences.
Metric
Boise City
Idaho
Rockford
Illinois
Population
Median Household Income
Annual
Median Gross Rent
Per month
Median Home Value
Cost of Living Index
US avg = 100
1BR Fair Market Rent
HUD FMR
2BR Fair Market Rent
HUD FMR
3BR Fair Market Rent
HUD FMR
Air Quality Index
Lower = cleaner
Top State Income Tax
Top marginal rate
State Sales Tax
Statewide base rate
Median Age
Years
✓ = better value · Sources: Census ACS, BEA, HUD Fair Market Rents, EPA AirNow, Tax Foundation
Renters will find significantly cheaper housing in Rockford — median rent of $985/mo versus $1,446/mo in Boise City, a 32% difference. Home buyers face a steeper market in Boise City: the median home is $484,800 versus $129,000 in Rockford — 73% more expensive.
Metric
Boise City
Rockford
Software Developer
Registered Nurse
Elementary Teacher
Electrician
Accountant
Higher wage highlighted · BLS OEWS 2023 (metro-level data)
State tax data is not yet available for these cities.
Boise City
Income tax: N/A
Sales tax: N/A
Rockford
Income tax: N/A
Sales tax: N/A
Rockford has cleaner air on average: 23.0 AQI (Good) compared to 36.0 AQI (Good) in the other city. Lower AQI means cleaner, healthier air.
Pick Boise City if you prioritize higher median household income ($83,904/yr).
Pick Rockford if you prioritize cheaper rent ($985/mo median).
Pick Rockford if you prioritize cleaner air quality (avg AQI 23.0).
Boise City is cheaper overall, with a cost of living index of 89.4 versus 90.2 (US average = 100). That means prices run about 1% lower in Boise City.
Median rent is $1,446/mo in Boise City, ID and $985/mo in Rockford, IL. Rockford, IL has the lower rent by about 32%.
Median household income is $83,904 in Boise City, ID and $54,752 in Rockford, IL. Boise City, ID has the higher median income. Note that BLS occupational wages in the table above show wages for specific jobs.
Rockford, IL has better air quality on average: 23.0 AQI versus 36.0 AQI. Both are EPA AirNow annual averages; lower is better.
State tax data is not yet available for one or both cities.
To maintain the same purchasing power, a salary of $100,000 in Boise City, ID is equivalent to roughly $100,909 in Rockford, IL (using the BEA Regional Price Parity ratio). Use the salary calculator above for any income amount.
Data last updated: June 1, 2026 · Sources: US Census ACS, BEA RPP, BLS OEWS, HUD FMR, EPA AirNow, Tax Foundation · Methodology
