How Much Does an ADU Cost in Fresno, CA?

Construction Cost Breakdown

Building an ADU in Fresno costs between $80,000-$200,000 for new construction, with per-square-foot costs averaging $120-$250. These figures include design, permitting, site preparation, and construction. The most affordable option is a garage conversion at $50,000-$120,000, while prefab/modular ADUs fall in between at $70,000-$180,000.

Permit Costs & Timeline

Permit fees in Fresno are City-published figures for a pre-approved-plan ADU: Plans FREE, Plan Check FREE, Building Permit 'Up to $2,400', School Impact Fee varies by sq ft (school fee is the district's, not the city's). Underlying Master Fee Schedule rates (fees effective 07/01/2025): R-3 One or Two-Family Production/Repeat/Standard Plan Infill = $34.89 plan check base + $1,279.35 inspection base at the 1,000 sq ft threshold. A custom-designed ADU instead uses R-3 (Custom): $580.69 plan check + $1,884.77 inspection at the same threshold. A CBSC surcharge of $1-$4 by valuation also applies. Do not publish a single range without splitting standard-plan vs custom.. The review timeline is City-published turnaround for pre-approved (standard) plans: completed applications reviewed in approx. 14 days; the application packet states the initial plan check takes approx. 7 business days once the application moves into review. Fresno's code sets no local deadline of its own; the 60-day figure is the state ministerial deadline, not a Fresno fact., with plan check: Standard review. Impact fees are None below 750 sq ft. At 750 sq ft and above Fresno charges the flat MULTI-FAMILY residential rate rather than a proportional share of the primary dwelling: Fire Impact Fee $1,738.74/unit; Park Facility Impact Fee $2,681.44 + $1,161.16 land = $3,842.60; Traffic Signal Mitigation $589.56/unit (all per the Master Fee Schedule, fees effective 07/01/2025, adjusted each July 1 by the ENR 20-City CCI). The city's ADU application packet also notes that only Plan #5 (1,015 sq ft) triggers a Regional Transportation Mitigation Fee JPA form. Flag: the flat multi-family rate is not the proportional method Gov. Code 66311.5(c)(2) prescribes — worth a hedge rather than a flat assertion of legality.. Pre-approved plans: Yes, and still live as of June 2026. Five FREE pre-approved construction-drawing sets in three exterior styles (Contemporary, Craftsman, Gable): Plan 1 = 340 sq ft studio (23-TADU-001), Plan 2 = 499 sq ft 1-bed (002), Plan 3 = 625 sq ft 1-2 bed (003), Plan 4 = 625 sq ft over a 625 sq ft garage (004), Plan 5 = 1,015 sq ft 3-bed 2-bath (005). Plans and plan check are free; the homeowner supplies only a plot plan and an options table. Note plans 1-4 are all under 750 sq ft, i.e. impact-fee exempt — that is the single biggest cost lever on the page..

Rental Income & ROI

A typical ADU in Fresno generates approximately $14,400 per year in rental income based on average 1-bedroom rents. At an average construction cost of $140,000, the estimated payback period is 9.7 years — before accounting for the resale value the ADU adds, which an appraiser determines from comparable sales in Fresno and varies by market (often less than build cost).

Ways to Reduce ADU Costs in Fresno