Cost of accessory dwelling unit — San Antonio, TX

Last updated: September 24, 2026

What affects the price

Building an ADU is a custom project, so costs vary based on your specific choices. Site conditions are the biggest factor; if your land requires significant grading, utility extensions, or foundation work, those expenses add up quickly. Choosing high-end finishes, custom cabinetry, or complex roof lines will also push the budget higher compared to a standard design. Prefabricated units often offer predictable costs, while custom site-built structures allow for more flexibility but can be harder to estimate upfront. Exact pricing confirmed free on the call.

About this service

The total investment for an ADU depends on several moving parts, including your property’s site conditions, the complexity of your site plan, and the high-end finishes you select. Whether you are building a detached cottage or converting a garage, costs vary based on utility connections and local labor rates. Exact pricing confirmed free on the call.

Frequently asked in San Antonio

Also serving nearby: New Braunfels · Austin · Round Rock · Georgetown · Killeen

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More on this: HUD ADU resources — ADU policy and financing research.

Service area details

Serving all of San Antonio — population 1,495,295; about 2,997 residents per square mile across 498.9 sq mi. ZIP codes covered include 78201, 78202, 78203, 78204, 78205, 78206, 78207, 78208.

Neighborhoods served in San Antonio: King William, The Pearl, Alamo Heights, Southtown, Stone Oak, Olmos Park — and every surrounding area.