Impact Fees

Name: Upside ADU
Address: Sacramento, CA, US
Telephone: (916) 282-5283
Price range: $$$

Also: development impact fees

Impact fees are one-time charges local governments levy on new construction to fund infrastructure. Under California law, ADUs under 750 square feet are fully exempt from impact fees — which is why many Sacramento owners deliberately size a unit just under that threshold to save thousands to over $20,000.

Above 750 sq ft, impact fees must be charged proportionally to the main house's size, not at a flat rate. The 750 sq ft exemption is the single largest cost lever a homeowner controls.

Go deeper:How much does an ADU cost in Sacramento

Related terms

Mello-Roos (CFD)Floor Area Ratio (FAR)

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