Backyard accessory dwelling unit — Billings, MT
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
This is a standalone structure built on your property, separate from your main house. People usually build these when they have extra yard space and want to create a private living area for family members or a home office. Factors like site accessibility, utility connections, and foundation type move the price up or down. Exact pricing confirmed free on the call.
Frequently asked in Billings
What are modular accessory dwelling units in Billings?
What is the cost to build an accessory dwelling unit in Billings?
What are emergency ADUs and are they available in Billings?
Can I build a home with in-law suites in Billings?
What is an accessory dwelling unit?
An accessory dwelling unit, or ADU, is a secondary, independent living space on a single-family residential lot. It typically includes its own kitchen, bathroom, and sleeping area. ADUs can be attached to the main house or be a separate structure, like a backyard cottage. They offer homeowners flexibility for various housing needs. In Billings, they are a valuable addition.
What is the cost of an accessory dwelling unit in Billings?
How do I get an ADU estimate in Billings?
Also serving nearby: Salt Lake City · West Valley City · Sandy · West Jordan · Fort Collins
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Billings — population 120,864; about 2,652 residents per square mile across 45.6 sq mi. ZIP codes covered include 59101, 59102, 59103, 59104, 59105, 59106, 59107, 59108.
Neighborhoods served in Billings: Lockwood, West Billings, South Billings, North Park, Midtown Billings — and every surrounding area.
Areas we serve
Browse by state, then city.