Cost of accessory dwelling unit

Looking for cost of accessory dwelling unit in Fort Collins, CO? Call AccessoryDwellingUnit Pros for a contact a provider — no obligation. Licensed adu builders serve Fort Collins and the surrounding area, and you'll get straight answers on timing and what affects the price.

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 Fort Collins

What are the disadvantages of ADUs in Fort Collins?

Potential downsides include the initial investment and the possibility of reduced yard space. Permitting processes can also take time, depending on the specifics of your Fort Collins location. It's wise to discuss these factors with the pros who handle your estimate.

How much does an ADU cost in Colorado?

ADU costs in Colorado vary widely based on size, materials, and site complexity specific to your Fort Collins property. Factors like foundation needs or utility connections will influence the final price. Get a personalized quote to understand your project's specific cost.

What are the rules for ADUs in Colorado?

Is an ADU allowed in Fort Collins?

What should I know about ADU permits in Fort Collins?

Also serving nearby: Greeley · Longmont · Boulder · Thornton · Westminster

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

Service area details

170,376residents

2,976per sq mile

8ZIP codes served

Serving all of Fort Collins — population 170,376; about 2,976 residents per square mile across 57.2 sq mi. ZIP codes covered include 80521, 80522, 80523, 80524, 80525, 80526, 80527, 80528.

Neighborhoods served in Fort Collins: Old Town Fort Collins, Harmony Corridor, Drake, Rigden Park, Midtown — and every surrounding area.