Short answer: published 2026 ranges for replacing a gas furnace in the Portland metro are $3,141–$6,281 (Angi, average $4,711) and $4,350–$7,750 (Costadia). No source publishes a Clackamas-only figure. Oregon does not require a heat pump for a replacement, and the only 2026 gas-furnace incentive excludes owner-occupied detached houses. Compare quotes on total installed price, with model numbers.
Does Oregon require a heat pump when you replace a furnace?
No. Section N1105.8 of the 2026 Oregon Residential Specialty Code applies to new dwellings where split-system air-conditioning is installed. The Building Codes Division's own technical summary says it “is for new dwellings only and does not apply to the replacement (alteration) of an existing cooling system,” and that it “does not dictate the heating system fuel for the home.” If a quote for a replacement is built around “the state requires a heat pump now,” ask which code section requires it for your replacement. The full code language is here.
What does a furnace replacement cost in 2026 in Clackamas County and Portland?
The published 2026 ranges for a gas furnace replacement in the Portland metro: Angi puts it at $3,141–$6,281 (average $4,711); Costadia's 2026 Portland guide says $4,350–$7,750. Neither publishes a separate figure for Clackamas County, and this site will not invent one: Happy Valley, Oregon City and Milwaukie are inside the same metro market those guides describe. For comparison, Angi's Portland figure for a ducted heat pump is $4,763–$9,116 (average $6,915). Published ranges disagree because almost none of them say what is included — equipment only, equipment plus labor, or the complete job with permit, electrical and duct work are three different numbers. The full table, with what actually moves your number, is here.
The lesson from the table is not a number. It is to stop comparing your quote with an internet average and compare quotes with each other, on total installed price, with model numbers attached.
What a total installed price should list
| Line | What it should say | Why it moves the price |
|---|---|---|
| Equipment | Manufacturer, model number and AFUE, in writing | “High-efficiency” is not a specification; the model number is what you compare |
| Venting and condensate | New PVC vent route and a condensate drain, if it is a 90%-plus condensing furnace | A real cost that a low quote can leave out |
| Ductwork | Which duct changes, if any, are included | The biggest single swing on the cost page |
| Permit | Who pulls it, and whether the fee is in the price | Permitted work is inspected work |
| Electrical | Any circuit or panel work, and who does it | A separate trade and sometimes a separate permit |
| Removal | Haul-away of the old furnace | Often missing from the cheapest quote |
| Rebate | If a rebate is subtracted: the program name and its document | A rebate you do not qualify for is not a discount |
| Warranty | Parts warranty and labor warranty, separately, with their lengths | Labor warranties are where contractors actually differ |
What a permit costs, one real example: the City of Gresham’s residential mechanical permit application (form revision 07/01/2026) charges $44 per fixture, counts “furnace and its attached add-ons” as one fixture, has a $130 minimum, and adds a 12% state surcharge. Clackamas County and the cities in it set their own fees; this site has not read those schedules, so it gives no figure for them. The Gresham guide has the detail.
What a proper install includes
- A load calculation for the house, not a copy of the old unit's size. Manual J is the ACCA residential load-calculation standard. An oversized furnace short-cycles and wastes fuel; the old one may have been oversized too.
- An assessment of the ductwork and venting. A condensing furnace — the 90%-plus AFUE class — produces acidic condensate and vents through PVC rather than the metal flue, so it needs a drain and a new vent route. That is a real cost and a legitimate line on a quote; it should be visible, not buried.
- The permit. Ask who pulls it. Permitted work is inspected work.
- Commissioning. Temperature rise within the range on the nameplate, gas pressure set, and a combustion or carbon-monoxide check. Ask for the readings.
- Removal and disposal of the old furnace, stated in the price.
The efficiency rating
A furnace's efficiency is its AFUE (annual fuel utilization efficiency). Ask for it in writing for the exact model number, and compare quotes at the same AFUE with the same install scope. A higher AFUE costs more to buy and less to run; whether the difference pays back depends on your gas bill and how long you will own the house, and no page can do that arithmetic for you without both numbers.
Is there a rebate for a new gas furnace?
Only a narrow one. Energy Trust of Oregon’s 2026 Oregon sheet (PI 0320I v2026.5, revised 9 September 2026) lists $1,600 for a 95% AFUE or better furnace that is the home’s primary heat, but only for a single-family rental, an attached home, or an income-qualified household (Savings Within Reach), and only where the gas comes from NW Natural, Cascade Natural Gas or Avista. It lists no gas-furnace incentive for an owner-occupied detached house. It is not paid on a hybrid system and needs a CO monitor on every floor with a bedroom. The heat-pump incentives on the rebate page require the heat pump to replace electric heat, so they do not apply to a furnace swap. If a quote leans on a rebate, ask for the program name and the document it comes from.
The heat-pump question, put fairly
You are not required to buy a heat pump. You may still want one: a heat pump paired with a new gas furnace — the dual-fuel arrangement — uses the heat pump as first-stage heating and the furnace below a set-point temperature, and the 2026 code language explicitly contemplates that pairing for new homes. If a contractor proposes it, ask for the furnace-only price and the dual-fuel price side by side, with model numbers and the switch-over temperature, and read the heat pump guide before deciding.
Four questions before you sign anything
- What is your CCB number? Then check it. Hesitation is an answer.
- Which equipment, exactly? Manufacturer, model number, and the AFUE, HSPF2 or SEER2 rating in writing. “High-efficiency” is not a specification, and rebate eligibility turns on the exact rating.
- What is the total installed price — permit, electrical, duct changes and haul-away included — not the price after a rebate you may not qualify for?
- Who pulls the permit? If the answer is “we don't usually,” that is the answer.
Licensed furnace installers near you
The state record lists 155 heating, cooling and mechanical businesses registered in Clackamas County and 104 in Multnomah County. By registered city (where the license is held, not where they work):
| City | Licensed businesses | Licensed 10+ years | Local guide |
|---|---|---|---|
| Clackamas | 20 licensed | 16 | Clackamas furnace guide |
| Happy Valley | 11 licensed | 4 | Happy Valley furnace guide |
| Milwaukie | 13 licensed | 8 | Milwaukie furnace guide |
| Oregon City | 19 licensed | 8 | Oregon City furnace guide |
| Gladstone | 3 licensed | 2 | Gladstone furnace guide |
| Damascus | 14 licensed | 4 | Damascus furnace guide |
| Gresham | 20 licensed | 11 | Gresham furnace guide |
| Portland | 78 licensed | 35 | — |
Each local guide adds who issues the furnace permit in that city. Ready for prices? Get up to 3 quotes for a furnace replacement, pre-filled.
Nearby
Sources and how this page was researched
Who: written and checked by Mark Griffin for Direct-Me LLC, the publisher. Neither is an HVAC contractor or technician, and nothing here comes from inspecting anyone’s equipment. What the page adds is the primary documents, read and dated:
- Licensed contractors: the State of Oregon’s CCB Active Licenses open data (data.oregon.gov, dataset g77e-6bhs), state copy dated 13 September 2026, pulled 23 September 2026, filtered to 1,042 heating, cooling, mechanical, refrigeration and sheet-metal businesses. Every count on this page is computed from that file when the site is built; none is typed in by hand. A general contractor who also installs furnaces will not be in the filter.
- Costs: Angi (Portland) and Costadia (Portland, 2026), verified 23 September 2026. No source publishes a town-level figure and no repair-price range could be verified, so this page gives none.
- Incentives: Energy Trust of Oregon information sheet PI 0320I v2026.5 (revised 9 September 2026), Oregon section, re-read 29 September 2026; IRS guidance on Public Law 119-21 for the end of the 25C credit.
- Code: Oregon Building Codes Division, First-Stage Heat Pump — 2026 ORSC Provisions Summary, quoted verbatim, read 23 September 2026. Its effective date has not been re-confirmed since; call the Building Codes Division (503-378-4133) if a date matters to your project.
- Permit fee example: City of Gresham, Mechanical Permit Application – Residential, form revision 07/01/2026, read 7 October 2026. Clackamas County’s and the other cities’ fee schedules were not read for this page, so no fee is given for them.
No contractor, manufacturer or program pays to appear or to be mentioned. Found an error? Send it with the source; the page is corrected and re-dated.
Sources. Cost ranges are quoted from the published 2026 guides named on the cost page (Angi Portland; Costadia Portland 2026), as verified there on 23 September 2026. Incentive figures and equipment conditions are from Energy Trust of Oregon information sheets PI 0320I v2026.5 and PI 0320I-HP v2026.4 (both revised 9 September 2026), IRS guidance on Public Law 119-21, and Oregon Department of Energy program pages, as verified on the rebate page. Code language is quoted from the Oregon Building Codes Division technical summary First-Stage Heat Pump — 2026 ORSC Provisions Summary. License facts are from the State of Oregon CCB Active Licenses open dataset g77e-6bhs. This page is general information, not a bid, a code ruling or tax advice.