Adu cost — Bellevue, WA
Last updated: September 24, 2026
What affects the price
Building an ADU is a major project, and the final bill depends on a few key things. Site prep is a big factor; if your land is sloped or needs extensive utility connections, costs go up. The materials you choose—from siding to kitchen finishes—also change the math significantly. Whether you’re building a detached unit or converting an existing garage shifts the permit requirements and structural work needed. We provide exact pricing confirmed free on the call.
About this service
Total ADU costs are driven by the foundation type, the complexity of plumbing and electrical runs, and your choice of fixtures. We provide a clear breakdown of where your money goes so you know exactly what you are paying for from day one. Exact pricing confirmed free on the call.
Frequently asked in Bellevue
What kind of companies build accessory dwelling units in Bellevue?
What are the local rules for accessory dwelling units in Bellevue?
Can I build an in-law suite in Bellevue?
What is the definition of an accessory dwelling unit?
An accessory dwelling unit (ADU) is a secondary housing unit on a single-family residential lot. It's typically a smaller, independent living space. This can be a detached structure or an attached addition to the main home. ADUs provide flexibility for homeowners. They can be used for family, guests, or rental income.
How much does it typically cost to build an accessory dwelling unit in Bellevue?
Do you offer emergency ADU services in Bellevue?
Are accessory dwelling units for rent in Bellevue?
Also serving nearby: Kirkland · Renton · Seattle · Kent · Federal Way
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Bellevue — population 151,574; about 4,528 residents per square mile across 33.5 sq mi. ZIP codes covered include 98004, 98005, 98006, 98007, 98008, 98009, 98015.
Neighborhoods served in Bellevue: Medina, Factoria, Eastgate, Downtown Bellevue, Overlake — and every surrounding area.
Areas we serve
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