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.

Verified August 2026

Does furnace replacement cost cost more in Illinois?

+9% versus the national baseline

Chicago runs its own building code and licensed-trade requirements distinct from the rest of Illinois, so city and suburban pricing diverge substantially. Permit fees here run about 10% off the national average, and Homeowner permits allowed in most jurisdictions, restricted in Chicago

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 baseline1.09x national
Permit fee index1.10x national
Code basisAdopted locallyLocal adoption of the IRC; statewide plumbing and energy codes apply
Owner-builder postureHomeowner permits allowed in most jurisdictions, restricted in Chicago
Largest marketsChicago, 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.

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

Last verified August 2026. Cost figures are modeled estimates based on national baselines adjusted for local labor and material pricing — they are not quotes. Permit rules change; confirm with the building department before starting work.