State law bars impact fees on an ADU of 750 sq ft or less. The County Parks schedule exempts ADUs up to 850 sq ft, or up to 1,000 sq ft with multiple bedrooms; building permit and school district fees still need a separate assessment.
Last verified 2026-10-18. Rules change; the Sacramento County planning desk has the final word.
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The County Parks schedule exempts ADUs of 850 sq ft or less, and multi-bedroom ADUs of 1,000 sq ft or less. Larger ADUs pay a fee no greater than the share proportional to the main house. The state impact-fee exemption is 750 sq ft or less; other fees still need their own review.
Sacramento County Parks Development Fee Schedule (March 2026); Gov. Code 66311.5(c)(1)Ask the Sacramento County planning desk before you rely on these.
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No. Gov. Code 66311.5(c)(1) bars impact fees on an ADU of 750 sq ft or less. The Sacramento County Parks schedule has a separate exemption through 850 sq ft, or through 1,000 sq ft for a multi-bedroom ADU; it does not set every other County fee.
It depends on the school district. San Juan Unified's 2026 developer-fee page supports an estimated charge at its published $5.38 per sq ft rate and excludes ADUs under 750 sq ft; Twin Rivers Unified's 2026 page supports an estimated charge at its published $5.38 per sq ft rate for ADUs of 500 sq ft or more. Ask the district for a final amount.
The County ADU and JADU guide (V8, p. 8) says to expect building permit fees for any project. Gov. Code 66311.5(c)(1) addresses impact fees, and the amount of a building permit fee needs a project-specific quote.
Neither. It is a screening from public records, not professional advice, and not a survey, soils report, appraisal, loan offer or permit; every number is an estimate. A licensed designer confirms the final plan, and your city or county gives final approval.