Quick answer
Colorado has lower average 1BR rent ($1,595/mo vs $1,850/mo). State income tax: Colorado (4.4%) vs Illinois (4.95%) — on a $120K salary that's $660/year difference.
State Comparison · 2026
Colorado 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
Colorado vs Illinois at a Glance
| Metric | Colorado | Illinois |
|---|---|---|
| Avg 1BR rent (major metros) | $1,595 ✓ | $1,850 |
| Avg median home price | $515K | $340K ✓ |
| Cheapest city | Colorado Springs ($1,450) ✓ | Chicago ($1,850) |
| Priciest city | Denver ($1,740) | Chicago ($1,850) |
| State income tax | 4.4% ✓ | 4.95% |
| Avg walkability | 49/100 | 78/100 ✓ |
| Cities tracked | 2 | 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: Colorado (4.4%).
Salary $80K
$440
/year saved in Colorado
Salary $120K
$660
/year saved in Colorado
Salary $200K
$1,100
/year saved in Colorado
Calculation uses the effective state rate difference × gross salary. Doesn't include property tax, sales tax, or federal impact.
Deep Dive: Each State
Colorado (CO)
Tax reality
Colorado has a flat 4.4% state income tax — lower than California or New York but not zero. The TABOR amendment caps annual state revenue growth, which occasionally triggers tax refunds (a few hundred dollars per taxpayer) but also starves state services. Property tax is low (~0.5% effective).
Top cities (2 tracked)
Top drawbacks
- ✕Altitude takes 3-6 weeks to adjust to and permanently affects endurance sports performance vs sea level. Some people never fully adjust.
- ✕Winter driving the I-70 corridor to ski resorts is regularly miserable. Traction laws can close passes entirely, and Friday/Sunday traffic in season is 3-5 hour crawls for a 90-minute drive.
- ✕Water is structurally tight. Denver specifically has growing supply concerns as the population expands and Colorado River allocations contract. Homes with big lawns are increasingly a liability.
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 Colorado or Illinois cheaper to live in?
Colorado has lower average 1BR rent across major metros — $1,595/mo vs $1,850/mo in Illinois, a $255/mo difference. Home prices: Illinois median is $340K vs $515K.
Colorado vs Illinois: which has lower state income tax?
Colorado has lower state income tax (4.4%) vs 4.95% in Illinois. On an $80K salary that's $440/year in savings. On $200K, savings grow to $1,100/year.
Should I move from Colorado to Illinois?
Colorado has a flat 4.4% state income tax — lower than California or New York but not zero. The TABOR amendment caps annual state revenue growth, which occasionally triggers tax refunds (a few hundred dollars per taxpayer) but also starves state services. Property tax is low (~0.5% effective).
What are the best cities in Colorado vs Illinois?
Colorado's largest metros include Denver, Colorado Springs. Illinois's largest metros include Chicago. Cost of living varies significantly within each state — a Colorado suburb can be 40% cheaper than its flagship city, and vice versa.