Home Addition Cost in Portland (2026): Average Price & Estimate

Home Addition Cost in Portland

Estimated home addition cost in Portland

$46,400–$139,200

Roughly about 16% above the national average.

Wet climate and labor costs lift prices above average.

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Addition type

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Based on Portland, OR pricing.

Estimated cost range

$46,400–$139,200

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An estimate for planning, not a quote. Get written quotes from local pros below.

Estimate, not a quote. Local prices vary by contractor and project. These are 2026 estimates for Portland, OR. Get written quotes from licensed Portland contractors before you budget.

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What to know about home addition in Portland

Soil movement around Portland is usually modest, but local soil type still drives the right approach.

What affects home addition cost in Portland

Beyond the local market, the same factors that drive home addition cost everywhere apply in Portland:

Addition size in square feet.
Type: a bump-out is cheapest, a second-story addition the most expensive.
Whether it includes a kitchen or bathroom (plumbing).
Foundation, framing, roof, and tie-in to the existing structure.

Home Addition cost by addition type in Portland

These figures are adjusted for Portland pricing (about 1.16x the national average), so they reflect what local homeowners actually pay.

Estimated home addition cost by addition type in Portland (2026)

Addition type	Cost in Portland	Typical total
Bump-out (a few feet)	$92.80 to $278 /sq ft	About $37,100 to $111,400
Sunroom	$104 to $313 /sq ft	About $41,800 to $125,300
Single room addition	$116 to $348 /sq ft	About $46,400 to $139,200
In-law / suite with bath	$139 to $418 /sq ft	About $55,700 to $167,000
Second-story addition	$162 to $487 /sq ft	About $65,000 to $194,900

Frequently asked questions

How much does home addition cost in Portland?

In Portland, OR, home addition typically costs $46,400 to $139,200 in 2026 for a standard project, about 16% above the national average. Your exact price depends on size, materials, and scope.

Why does home addition cost more or less in Portland?

Wet climate and labor costs lift prices above average. Labor rates, permit costs, and local demand are the main reasons Portland prices differ from the national average.

Do I need a permit for home addition in Portland?

Most home addition projects require a permit. Requirements vary by city and Oregon jurisdiction, so confirm with your local building department. A licensed contractor usually pulls the permit for you.

When is the best time of year for home addition in Portland?

In Portland, the mild climate means most projects can run year-round, with only the occasional rainy stretch to plan around.

Is home addition cheaper outside Portland?

Sometimes. Portland runs about 16% above the national average. Nearby smaller towns with lower labor costs can come in cheaper, while denser urban areas often cost more. Always compare quotes from contractors who serve your specific area.