Quick answer
Idaho has lower average 1BR rent ($1,380/mo vs $1,850/mo). State income tax: Illinois (4.95%) vs Idaho (5.8%) — on a $120K salary that's $1,020/year difference.
State Comparison · 2026
Idaho vs Illinois
Side-by-side on state income tax, rent, home prices, climate, and top metros — with specific dollar numbers for every claim.
Last updated: April 23, 2026
Idaho vs Illinois at a Glance
| Metric | Idaho | Illinois |
|---|---|---|
| Avg 1BR rent (major metros) | $1,380 ✓ | $1,850 |
| Avg median home price | $445K | $340K ✓ |
| Cheapest city | Boise ($1,380) ✓ | Chicago ($1,850) |
| Priciest city | Boise ($1,380) | Chicago ($1,850) |
| State income tax | 5.8% | 4.95% ✓ |
| Avg walkability | 42/100 | 78/100 ✓ |
| Cities tracked | 1 | 1 |
✓ marks the lower or more favorable value. Averages use the major metros we track in each state.
State Income Tax: Real Savings
What the rate gap actually looks like in your paycheck. Lower rate: Illinois (4.95%).
Salary $80K
$680
/year saved in Illinois
Salary $120K
$1,020
/year saved in Illinois
Salary $200K
$1,700
/year saved in Illinois
Calculation uses the effective state rate difference × gross salary. Doesn't include property tax, sales tax, or federal impact.
Deep Dive: Each State
Idaho (ID)
Tax reality
Idaho has a 5.8% flat state income tax (moderate). Property tax is low (~0.6% effective). Sales tax 6%. No estate tax. Overall moderate tax burden.
Top cities (1 tracked)
Top drawbacks
- ✕Housing growth has outpaced wage growth. Long-time Idaho residents have been priced out of Boise proper.
- ✕Summer wildfire smoke affects air quality regularly — July through September can have multiple weeks of AQI 150-200+.
- ✕Idaho is deeply conservative politically, with some policy shifts (abortion, LGBTQ+, religion in schools) recently tightening. Boise specifically leans moderate; the rest of the state is more conservative.
Illinois (IL)
Tax reality
Illinois has a flat 4.95% state income tax (moderate) — but property taxes are among the highest in the US, averaging 2.1% effective. On a $350K Chicago home that's $7,400/year. Combined tax burden is higher than it looks. The state's pension underfunding creates long-term fiscal risk for homeowners.
Top cities (1 tracked)
Top drawbacks
- ✕Property tax is brutal — Cook County averages 2.3% effective. On a $500K home, that's $11,500/year. Homeowners feel this every month.
- ✕Chicago winters are genuinely cold. Lake-effect snow, mid-December through March subzero streaks, and winds off Lake Michigan can make it feel -20°F. This is the biggest filter for people considering moving here.
- ✕The state fiscal situation (pension debt, budget pressures) drives ongoing policy uncertainty — property tax, sales tax, and various fees continue to drift upward.
Frequently Asked Questions
Is Idaho or Illinois cheaper to live in?
Idaho has lower average 1BR rent across major metros — $1,380/mo vs $1,850/mo in Illinois, a $470/mo difference. Home prices: Illinois median is $340K vs $445K.
Idaho vs Illinois: which has lower state income tax?
Illinois has lower state income tax (4.95%) vs 5.8% in Idaho. On an $80K salary that's $680/year in savings. On $200K, savings grow to $1,700/year.
Should I move from Idaho to Illinois?
Idaho has a 5.8% flat state income tax (moderate). Property tax is low (~0.6% effective). Sales tax 6%. No estate tax. Overall moderate tax burden.
What are the best cities in Idaho vs Illinois?
Idaho's largest metros include Boise. Illinois's largest metros include Chicago. Cost of living varies significantly within each state — a Idaho suburb can be 40% cheaper than its flagship city, and vice versa.