Illinois pricing
Furnace Replacement Cost Calculator — Illinois
Estimate what a furnace replacement should cost by output, efficiency and venting work. Every figure below is already adjusted for Illinois labor and material pricing.
Model reviewed August 2026
Does furnace replacement cost cost more in Illinois?
+9% versus the national baseline
Installed prices in Illinois run about 9% above the national baseline. Permit fees are about 10% higher than the national average. Homeowner permits allowed in most jurisdictions, restricted in Chicago.
Chicago runs its own building code and licensed-trade requirements distinct from the rest of Illinois, so city and suburban pricing diverge substantially.
Compare with the national average furnace replacement cost calculator.
Estimated installed cost
$5,098 – $7,242
- Furnace and labor
- $5,232
- Venting work
- $0
- Removal and permit
- $561
Estimates only. Local pricing, site conditions and code requirements change the real number.
What changes the number in Illinois
| Local cost indexAbove the national baseline | 1.09x national |
|---|---|
| Permit fee index | 1.10x national |
| Code basisAdopted locally | Local adoption of the IRC; statewide plumbing and energy codes apply |
| Owner-builder posture | Homeowner permits allowed in most jurisdictions, restricted in Chicago |
| Largest markets | Chicago, Aurora, Naperville, Rockford |
The formula
Cost = base unit cost x efficiency multiplier + venting + removal + permit
High-efficiency condensing furnaces (90%+ AFUE) need new PVC venting and a condensate drain, which is why the jump from 80% to 96% AFUE costs more than the equipment difference alone.
Covered markets in Illinois
City-level cost and permit pages with local building department links.
Frequently asked questions
How much is a new furnace installed?
Most homeowners pay $4,000 to $8,500 for a replacement gas furnace in 2026. Electric furnaces are cheaper to install but cost far more to run.
How long does a furnace last?
15 to 20 years for a gas furnace with annual service. Past year 15, repairs over about $1,500 usually favor replacement.
Sources
Sources & verification
- Illinois Capital Development Board
- ENERGY STAR sizing and efficiency guidance
- ACCA Manual J / Manual S sizing standards
- AHRI equipment performance directory
- International Code Council (IRC/IBC)
Model vintage August 2026. The links above are the issuing agencies' own pages — we publish them so you can confirm the current rule yourself, not as evidence that each fact on this page was re-checked with them today. Cost figures are modeled estimates based on national baselines adjusted for local labor and material pricing, not quotes. Permit rules change; confirm with the building department before starting work.