ADU Permits: Hesperia vs Rialto
How do adu permits rules compare between Hesperia, CA and Rialto, CA?
Hesperia has fewer restrictions than Rialto.
Hesperia, CA
San Bernardino County
Hesperia's Development Services Department issues ADU permits ministerially under HMC 16.12.360. California Gov. Code 66317 mandates approval or denial of a complete ADU application within 60 days (the Hesperia ordinance still references the older 120-day window).
View full Hesperia rules →Rialto, CA
San Bernardino County
ADU permits are issued by the Rialto Building & Safety Division (150 S Palm Ave). State law (Gov. Code §66317) requires the city to act on a complete ADU application within 60 days, ministerially, with no discretionary hearing. Plans must comply with the California Building Standards Code (effective 2025 edition as of Jan. 1, 2026) and RMC Title 15.
View full Rialto rules →Key Facts Comparison
| Fact | Hesperia | Rialto |
|---|---|---|
| Permitting Department | Development Services Department | - |
| Review Timeline (State) | 60 days (Cal. Gov. Code 66317) | - |
| Review Timeline (Local Text) | 120 days per HMC 16.12.360 (preempted by state) | - |
| Hearing Required | No - ministerial approval only | - |
| City Hall Phone | (760) 947-1200 | - |
| Permit issuer | - | Rialto Building & Safety Division |
| Address | - | 150 S Palm Avenue, Rialto, CA 92376 |
| Phone | - | (909) 820-2505 |
| Statutory review window | - | 60 days (Cal. Gov. Code §66317(b)) |
| Code edition | - | 2025 California Building Standards (effective Jan. 1, 2026) |
Highlighted rows indicate differences between cities.
Hesperia FAQ
How long does Hesperia have to approve an ADU permit?
60 days from a complete application under California Gov. Code 66317. Hesperia's local text still says 120 days, but state law preempts and the city must act within 60 days or the permit is deemed approved.
Do I need a public hearing for an ADU in Hesperia?
No. ADUs that comply with HMC 16.12.360 are approved ministerially by Development Services with no Planning Commission hearing or discretionary review.
Rialto FAQ
How long does Rialto have to approve my ADU permit?
60 days from a complete application under Gov. Code §66317(b). If the city doesn't act, the permit is deemed approved.
Can I submit ADU plans online?
Yes. Rialto's Online Permit Center (OPC) accepts submittals — link your account through the Building & Safety Division page or apply at the counter (150 S Palm Ave, Mon-Fri 7 AM-6 PM).
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