Compare taxes and see how much you save moving from Illinois to Colorado
The mountain escape with massive property tax savings. Colorado's 4.4% flat rate beats Illinois' 4.95%, saving $550/year at $100K income. But property tax is where Colorado dominates: 0.48% (10th-lowest nationally) vs Illinois 2.08% (2nd-highest). On $400K home: CO pays $1,920/year vs IL $8,320—CO saves $6,400 annually. Total at $100K + $400K home: Colorado saves $6,950/year. Denver's tech boom, 300+ days of sunshine, and world-class outdoor recreation make it attractive despite higher housing costs ($590K Denver vs $350K Chicago). Illinois pension crisis threatens future tax hikes; Colorado's TABOR amendment limits increases.
Flat Tax
Flat rate + high property
Flat Tax
Recently reduced to 4.4%
At $100,000 income:
That is CO saves $579/month total back in your pocket!
| Income | IL Tax | CO Tax | Savings | 10-Year |
|---|---|---|---|---|
| $50,000 | $2,475 | $2,200 | CO saves $275 | $2,750 |
| $75,000 | $3,713 | $3,300 | CO saves $413 | $4,130 |
| $100,000 | $4,950 | $4,400 | CO saves $550 | $5,500 |
| $150,000 | $7,425 | $6,600 | CO saves $825 | $8,250 |
| $250,000 | $12,375 | $11,000 | CO saves $1,375 | $13,750 |
| $500,000 | $24,750 | $22,000 | CO saves $2,750 | $27,500 |
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Moving from Illinois to Colorado? Multi-state returns are tricky—partial-year residency, different deadlines, avoiding double taxation. Get matched with a CPA who specializes in state moves. Virtual meetings, fixed pricing.
Get Matched With a CPA →Income tax at $100K: CO saves $550/year (IL $4,950 → CO $4,400). Property tax is dramatic: IL 2.08% vs CO 0.48% (10th-lowest nationally). On $400K home: IL pays $8,320/year vs CO $1,920—CO saves $6,400 annually. Total at $100K + $400K home: CO saves $6,950/year ($69,500 over 10 years). But watch housing costs: Denver $590K median vs Chicago $350K—Denver $240K more expensive upfront.
Complex. Denver median $590K vs Chicago $350K—Denver $240K more expensive. Over 30-year mortgage at 7%: Denver costs $3,200/month vs Chicago $2,332 ($868 more). Annual extra: $10,416. BUT CO saves $6,950/year (income + property tax). Net: Denver costs $3,466/year MORE. HOWEVER: Denver salaries often match or exceed Chicago ($87K vs $88K median) and outdoor lifestyle is premium. Choose Denver for lifestyle + tech jobs, Chicago for pure financial math.
Yes—optimal strategy. Establish Colorado residency (CO driver's license, spend majority time in CO), pay Colorado taxes (4.4%), not Illinois (4.95%). At $100K: save $550/year. Add property tax savings: CO $1,920 (0.48% × $400K) vs IL $8,320 (2.08%)—save $6,400/year. Total remote work advantage: $6,950/year. Many Chicago tech/finance workers move to Denver, keep Chicago salaries ($100-150K), pay CO taxes, enjoy 300 sunny days + mountains.
Denver tech scene growing fast: Google (Boulder, 1,500+ employees), Amazon (tech hub, 500+), aerospace (Lockheed Martin, Ball Aerospace), startups (Guild Education, Ibotta). Salaries: Denver $85-140K tech vs Chicago $90-150K (Chicago 5-10% higher). Chicago stronger in: fintech (Citadel, CME Group, trading firms), enterprise software. Choose Denver for: aerospace, outdoor lifestyle, growth. Choose Chicago for: peak fintech comp, established ecosystem.
Colorado's TABOR (Taxpayer Bill of Rights) amendment limits tax increases—requires voter approval for any tax/spending hikes. This keeps taxes stable (4.4% income, 0.48% property unlikely to rise dramatically). Illinois has NO such protection—legislature can raise taxes (happened 2011, 2017). Colorado's 4.4% rate recently reduced from 4.55% (2020) as TABOR refunds occur. For long-term tax stability, Colorado safer than Illinois (pension crisis threatens IL tax hikes).