The Governor approved SB 1117 (Chapter 809, Statutes of 2026) on September 29, 2026. It amends Gov. Code 66311.5: on lots with up to two ADUs, impact fees on an ADU over 750 sq ft must still be proportional to the primary home, and may only be charged on the area over 750 sq ft. Regular 2026 statutes take effect January 1, 2027. Until then, fees on a larger ADU are figured on its full size. Our calculator has a 2027 setting that shows the difference.
Mountain View's development fee table, effective August 22, 2026, sets the citywide transportation fee at $6,273.15 per new single-family unit, along with updated water and sewer capacity fees.
Palo Alto's August 2026 impact fee information sheet exempts ADUs under 750 sq ft from all development impact fees. Larger ADUs pay only the community-facility fees (parks, community centers, libraries, public safety, general government), proportional to the primary unit's size.
San José's Building Division fee schedule effective August 10, 2026 sets ADU building permit fees in two size bands (up to 750 sq ft, and 751–1,200 sq ft) for issuance, plan review and inspection. Our San José figures use it.
Scotts Valley's development impact fee schedule, effective July 7, 2026, restates that ADUs of 750 sq ft or less pay no development impact fees. It lists per-unit fees by zone and a separate "Second Unit" park fee of $7,018. A 4% administrative charge applies to impact fees.
Scotts Valley's master fee schedule for fiscal year 2026-27 took effect July 6, 2026. It sets the building plan check and processing scale on valuation, a 4% permit technology fee, and an ADU design review fee.
Watsonville's 2026-2027 schedule (dated July 1, 2026) adds a "New ADU" building fee: $2,455 base plus $4.00 per sq ft over 500 sq ft, marked as a new fee from the City's fee study. The schedule's header note on study fees reads "PER STUDY FEES WILL BE EFF. UNTIL 7/20/26".
Berkeley's fee schedule effective July 1, 2026 lists the ADU neighborhood notice ($500), the ADU zoning plan check ($250), and plan check at 50% of the regular fee for pre-approved ADU plans.
The Department of Housing and Community Development updated its ADU Handbook to reflect the laws that took effect January 1, 2026. Its proportional-fee example: a 1,000 sq ft ADU next to a 2,000 sq ft home pays 50% of the fee a new home would pay. Our models use 2,000 sq ft as the example primary-home size unless you enter your own.
On January 28, 2026 the State Allocation Board raised the statewide maximum Level 1 developer fee for residential construction from $5.17 to $5.38 per sq ft (+4.06%). School districts collect it on ADUs of 500 sq ft or more, at their own adopted rate up to this cap (higher Level 2/3 fees need extra findings). Where we haven't confirmed a district's rate, we use $5.38 as the upper bound.
SB 543 (Chapter 520, Statutes of 2025) took effect January 1, 2026. It restates the impact-fee rule in Gov. Code 66311.5: no impact fees on an ADU of 750 sq ft of interior livable space or less, or a JADU of 500 sq ft or less; above that, fees must be proportional to the primary home. It also caps JADUs at 500 sq ft of interior livable space. Many city documents still cite the older section numbers (65852.2 or 66324).
Santa Cruz's Planning and Community Development fee schedule, effective January 1, 2026 (updated 1/5/2026), completes the phase-in to 100% cost recovery for building fees. It keeps the reduced General Plan maintenance fee for ADUs (0.61% of valuation, against 1.22% for other projects).
On July 15, 2025 the Oakland City Council approved major updates to its impact fee program. From September 13, 2025, fees are charged per square foot and paid at certificate of occupancy. The amended chapters 15.72 and 15.74 keep ADUs exempt from the affordable housing, transportation and capital improvements impact fees.
AB 2533 (Chapter 834, Statutes of 2024) and SB 1211 (Chapter 296, Statutes of 2024) took effect January 1, 2025. AB 2533 moved the cutoff for legalizing unpermitted ADUs to units built before January 1, 2020; those owners pay no impact fees or connection charges except where utility work is needed. SB 1211 expanded detached ADUs on multifamily lots (up to eight, not more than the existing units).
AB 976 and AB 1033 (Chapters 751 and 752, Statutes of 2023) took effect January 1, 2024. Cities can no longer require the owner to live on a lot with an ADU (JADUs keep an owner-occupancy rule when sanitation is shared). Cities may opt in to allowing an ADU to be sold separately as a condominium.