City program

Pre-Approved ADU Plans in Seattle, Washington

Browse official and accepted pre-approved ADU plans for Seattle, Washington. Compare plan size, bedrooms, providers, approval status, official source links, permit requirements, and fees.

Program status: source-backed listings Last checked Aug 11, 2026

Program Overview

This Seattle page summarizes source-backed pre-approved ADU plan listings for Seattle, Washington, using official records tied to City of Seattle. The current public dataset lists 10 accepted plans from 10 providers; provider names include Abodu, CAST Architecture, Bohlin Cywinski Jackson, and others. The accepted listings are tied to the local Seattle program. Plan records cover 288 to 1,000 sq ft and 1 bedroom to 2 bedrooms where those fields were listed by the source.

Permit and fee context is kept separate from plan acceptance. The public dataset includes 3 permit requirement records and 1 fee record for Seattle. Permit requirement records include Pre-approved plan eligibility, Ground disturbance screening, and others. Fee records include Plan license fee. When a source did not publish a value, the page keeps that field as Not listed in source instead of filling a blank.

Use these listings as a starting point for matching a plan to a property. Source links, checked dates, acceptance notes, and provider records are shown so you can verify whether a plan remains accepted locally, what site-specific review remains, and whether local fees, plan licensing, or provider terms apply. A listing in this directory does not guarantee permit approval for a specific parcel.

Summary

Location
Seattle, King County, Washington, USA
Accepted plans
10 accepted plans
Providers
10 providers
Origin programs
1 program
Plan size range
288 to 1,000 sq ft
Permit sources
12 sources

How to use this page

  1. Pick a plan size and bedroom count.
  2. Check whether the plan originated locally or is accepted from another city/county program.
  3. Open the official source.
  4. Confirm current status with the local building department.
  5. Ask the provider what site-specific work, plan licensing, engineering, and utility review are still required.

Accepted Plans

10 plans

Permit Requirements

3 requirements

Fees

1 fee record

All

Plan license fee

Official city source

$750-$1,000 among plan pages with accessible published prices

Last checked
Aug 11, 2026
Notes
Exact price is retained on individual plan rows where verified; missing prices remain NULL.

Official Sources

12 sources

Seattle ADU FAQ

6 answers

Does Seattle have accepted or pre-approved ADU plans in this directory?

Yes. The current Seattle, Washington page lists 10 accepted plans from 10 providers in the source-backed export.

What ADU plan sizes are listed for Seattle?

The listed Seattle plan records range from 288 to 1,000 sq ft. Use the individual plan cards to confirm bedrooms, bathrooms, plan documents, and provider details because some fields are not listed by every official source.

Where do the Seattle ADU plan records come from?

They are tied to 12 official sources in this page's source set, including City of Seattle. Each plan, fee, and permit note should still be checked against the linked official source before use.

Can King County or nearby city ADU plans be used in Seattle?

The current Seattle records do not show accepted plans from a separate King County or nearby city program. Treat outside pre-approved plans as unavailable in Seattle unless an official Seattle source says they are accepted.

Do pre-approved ADU plans guarantee permits in Seattle?

No. A source-backed accepted plan can reduce plan review work, but Seattle can still require site-specific review, zoning checks, fees, utility coordination, and current code compliance. This page lists 3 permit requirements to help flag items to verify with the local building department.

Are Seattle ADU permit fees and requirements listed?

This page includes 1 fee record and 3 permit requirements for Seattle. These are source-backed summaries, not a final permit quote or approval checklist.