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Gas furnace replacement cost in Seattle, WA

Installed, 80,000 BTU, 95%+ efficiency

Low$4,600
Typical$5,100
High$6,350

Metro area: Seattle-Tacoma-Bellevue, WA. Wages: BLS, May 2025. Permit notes checked October 2026.

A typical furnace (80,000 BTU, 95%+ efficiency) costs about $5,100 installed in the Seattle area, 5% above the national figure, because HVAC technicians here earn a median $39 an hour against $29 nationally.

Gas furnace (80,000 BTU, 95%+ efficiency), installed

Prices for: Seattle-Tacoma-Bellevue, WA

Low$4,600
Typical$5,100
High$6,350

Unit $1,700 (online list price, middle of 9 listings) plus installation about $3,400 for this area. Permit fees and code extras are listed below the table.

How this estimate is built

Prices by size in Seattle

SizeLowTypicalHighNational typical
60,000 BTU, 80% efficiency$3,800$4,350$5,800$4,100
60,000 BTU, 95%+ efficiency$4,550$5,000$6,200$4,750
80,000 BTU, 80% efficiency$3,900$4,300$5,400$4,050
80,000 BTU, 95%+ efficiency$4,600$5,100$6,350$4,850
100,000 BTU, 80% efficiency$4,050$4,500$5,850$4,250
100,000 BTU, 95%+ efficiency$4,750$5,250$6,400$4,950

Local labor: what HVAC technicians earn here

Hourly wageSeattle metroUnited States
25th percentile$30$23
Median$39$29
75th percentile$49$37

The Seattle market

Seattle splits permits between two agencies. The Seattle Department of Construction and Inspections (SDCI) requires a permit for any furnace replacement or alteration and a refrigeration permit for any split-system heat pump or air conditioner. Plumbing and gas permits come from Public Health Seattle and King County, and no page found says whether a straight water heater replacement needs one, so check with Public Health. Homeowners may pull furnace and plumbing permits, but refrigeration permits go only to licensed refrigeration contractors. HVAC jobs need a cover inspection and a final inspection. Fees for these items were not confirmed. Many homes were built without air conditioning: EIA found only 53% of Washington homes use any AC, while 62% heat water with electricity. Tacoma, Bellevue and King County suburbs issue their own permits.

Furnaces provide main heat in 47% of Washington homes, often gas units in basements or crawlspaces. A crawlspace install is tight work, so ask how the crew will reach the unit and whether the ducts will be inspected while they are down there. If the quote also adds air conditioning, ask whether a heat pump paired with the furnace would cover cooling and much of the heating. Get the AFUE in writing.

Permits in Seattle

Permit for this jobYes (SDCI permit for any furnace replacement; refrigeration permit for split-system heat pumps and ACs) (source)
FeeUnclear for these items. Context: PHSKC plumbing/gas permits issued on/after Jan 1, 2025 use a $132 base fee plus $26 per fixture (water heater counting not stated); SDCI 2026 base hourly rate $292/hr with 6.5% inflationary increase to most fees.
Who can pull itFurnace/mechanical STFI: homeowner or contractor; refrigeration (heat pump/AC): licensed refrigeration contractor only; plumbing: homeowner permit or registered contractor via PHSKC
InspectionYes (HVAC: cover inspection and final inspection)

Rebates in Washington

HEAR: announced, not open yet. HOMES: announced, not open yet. Source: Washington State Department of Commerce, Energy Division, checked October 13, 2026.

What these programs cover, and other states

Other systems in Seattle

Gas furnace cost in other metros

Sources