A complete gas furnace replacement in the Chicago suburbs typically runs about $5,500 to $11,000 installed in 2026, according to a local cost guide, with national ranges starting lower. Where your job lands depends on furnace efficiency (80% vs 96% AFUE), size, venting and duct changes, and the permit. The federal 25C tax credit ended after 2025, but Nicor Gas still offers a rebate on qualifying high-efficiency furnaces in 2026.
Typical cost ranges
These are general market ranges, not quotes:
- Chicago suburbs: about $5,500 to $11,000 for a complete standard gas furnace replacement, including equipment and labor (TemperaturePro Mokena, 2026).
- National: about $3,600 to $10,000 for a natural gas furnace installed (HomeGnome, 2026).
Prices in the Chicago area tend to sit above national averages because of labor rates and the larger furnaces our winters need. Yogi Heating & Cooling gives every customer a written quote before any work starts.
80% vs 96% AFUE: which makes sense?
AFUE is the share of fuel that becomes heat in your home. A 96% AFUE furnace turns about 96 cents of every gas dollar into heat; an 80% furnace sends about 20% up the flue.
| 80% AFUE | 96% AFUE (condensing) | |
|---|---|---|
| Upfront cost | Lower | Higher |
| Gas use | More | Less |
| Venting | Metal flue, often into a chimney | PVC pipes through a wall or roof, plus a condensate drain |
| Nicor Gas rebate | Not eligible | Eligible at 95%+ AFUE |
In a cold climate like ours, high-efficiency furnaces usually make sense. ENERGY STAR estimates a certified gas furnace in the northern U.S. can save about $160 a year in energy costs. Switching from 80% to 90%+ can mean new venting, and if your water heater shared the old chimney, that chimney may need a liner (U.S. Department of Energy).
Also note: a federal rule upheld in court in 2025 requires most gas furnaces made on or after December 18, 2028 to be at least 95% AFUE. As of May 2026, DOE was considering a petition to delay it, so ask your contractor for the latest status.
Sizing matters: ask for a Manual J
Your new furnace should not just match the old one's size. Many older homes have oversized furnaces, especially after window or insulation upgrades. A room-by-room load calculation (ACCA Manual J) looks at your square footage, insulation, windows and air leaks to find the right size. An oversized furnace short cycles, heats unevenly and wears out faster. The Department of Energy recommends sizing by a heating contractor after any efficiency upgrades.
Permits
Most villages in our area require a permit to replace a furnace. Examples: Schaumburg treats it as an express permit with a $50 fee and a final inspection, and Palatine charges $103 per item and requires the contractor to be registered and bonded with the village. Fees and rules change, so your contractor should pull the permit for your village.
What changes the price
- Efficiency (80% vs 95%+ AFUE) and stage type (single-stage, two-stage, modulating)
- Variable-speed blower
- Size (BTUs) needed for your home
- New venting, chimney liner or condensate pump
- Duct repairs or changes, and tight attic or crawlspace access
- Gas line or electrical updates
- Permit fees and old unit removal
- Adding a new AC, heat pump or smart thermostat at the same time
Rebates and tax credits in 2026
Federal tax credit: The 25C Energy Efficient Home Improvement Credit only covers property placed in service through December 31, 2025, per the IRS. A furnace installed in 2026 does not qualify.
Nicor Gas rebate: For furnaces installed January 1 to December 31, 2026, Nicor Gas lists $150 for 95%+ AFUE and $225 for 97%+ AFUE, plus $50 more when you add a smart thermostat on the same application. Apply within 90 days of installation or by January 31, 2027, whichever comes first. Confirm current amounts at nicorgas.com/homerebates.
When to call a pro
If your furnace is aging, needs frequent repairs or you're planning ahead, get a written quote that includes a load calculation, the permit and rebate paperwork. Yogi Heating & Cooling installs furnaces across Schaumburg and the northwest suburbs. Call (814) 431-1709 or book an estimate, and ask about financing.
More questions
Is a 96% furnace worth it in Illinois?
Usually, yes. Our long heating season means the gas savings add up, and only 95%+ furnaces qualify for the Nicor Gas rebate. Venting changes can raise the upfront cost, so compare full quotes.
Can I still get a federal tax credit for a new furnace?
Not for a furnace installed in 2026. The IRS says the 25C credit applies to property placed in service through December 31, 2025.
Do I need a permit to replace my furnace?
In most of our area, yes. Villages like Schaumburg and Palatine require a permit and inspection, and your installer should pull it.
How long does furnace replacement take?
A straight swap is often done in one day. Jobs that need new venting, duct work or a chimney liner can take longer.
Should I replace my AC at the same time?
If your AC is near the end of its life, replacing both together can save on labor and make sure the indoor and outdoor parts are matched. Ask for prices both ways.
Related
- Furnace and heating repair
- Financing
- HVAC questions
- Reviews
- Why does my furnace keep turning on and off (short cycling)?
- Book service
Sources
- TemperaturePro Mokena - Cost to Replace a Furnace in 2026 (Chicago suburbs)
- HomeGnome - How Much Does a New Furnace Cost in 2026?
- IRS - Energy Efficient Home Improvement Credit
- Nicor Gas - Home Rebates (2026 program year)
- ENERGY STAR - Furnaces
- U.S. Department of Energy, Energy Saver - Furnaces and Boilers
- ACHR News - DOE upholds furnace efficiency standard (Nov 2025)
- ACCA - Department of Energy weighs delaying furnace rule (May 2026)
- Village of Schaumburg - Express Permits
- Village of Palatine - Furnace Replacement permit handout