What's the total ADU permit fee in Portland?

Total Portland ADU permit fees in 2026 run roughly $4,300–$11,500 depending on size, type, and any utility hookups required.

How long does Portland ADU permit review take?

Standard Portland ADU plan review takes 6–16 weeks. Pre-approved plans and complete submittals can shorten that significantly.

What fees are NOT included in the base Portland permit cost?

Utility connection fees (water, sewer, electric), school impact fees, drainage and fire-line upgrades, and any private-engineering studies typically add 30–60% to the base permit number.

Can I get my Portland ADU permit fees reduced or waived?

Some jurisdictions offer fee reductions for deed-restricted affordable ADUs, JADUs under 500 sq ft, or projects using pre-approved plans. Check Portland's current ADU ordinance for available waivers.

ADUCosts

Portland, OR

Portland ADU Permit Fee Calculator (2026)

Name: aduglossary.com — Portland OR ADU Resources
Price range: $

Instant fee breakdown for Portland, Oregon. Total range: $4,300–$11,500.

Portland, Oregon ADU Permit Fees

Total estimated range: $4,300–$11,500

Plan Check

$800–$2,000

Building Permit

$1,500–$3,500

Impact Fees

$0–$5,000

School Fees

N/A

Utility Hookups

$2,000–$6,000

Source: City permitting schedules and FeeBuilder surveys, updated April 2026.

Portland permit process at a glance

Permitting office: Portland Permitting & Development (PP&D)

Typical plan review: 12-20 weeks

Fee waivers: Portland waives System Development Charges (SDCs) for ADUs.

Portland's Residential Infill Project (RIP) opened nearly every R-zoned lot to ADUs and triplex conversions, and the city waives System Development Charges (SDCs) for ADUs entirely — that alone saves $8,000-$18,000 versus pre-2018 builds. The catch is Portland's wet climate: foundation drainage, deck flashing, and rain-screen wall assemblies are not optional, and a builder who's only worked in dry climates will under-bid the moisture detailing.

Sample real-world fee example

Scenario: 700 sq ft detached ADU on a typical Portland lot

Plan check (mid)	$1,000
Building permit (mid)	$1,800
Utility connection (low end)	$2,000
Misc fees (records, inspections)	$1,500
TOTAL (rough mid example)	~$5,800

Common Portland ADU permit mistakes

Not confirming SDC (System Development Charge) waiver status at intake — Portland still waives SDCs for ADUs but documentation matters.
Skipping rain-screen wall assembly detailing — Portland Permitting flags missing rain-screens regularly.
Forgetting the on-site stormwater management plan for impervious surfaces over 500 sq ft.

How Portland compares nearby

City	Total fee range	Link
Portland	$4,300–$11,500	(this page)
Seattle	$5,500–$14,000	View →
Denver	$6,300–$11,500	View →

Full Portland cost guide ROI calculator Compare all 18 cities

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