ADU Pass
Fontana
San Bernardino County portion
Also in: No County
ADU Pass helps homeowners in Fontana, San Bernardino County, California navigate the permit paperwork for building an accessory dwelling unit. This area covers 3 ZIP codes.
Map
ADU details
ADU legality: allowed
Permitted by-right under ministerial review. Fontana operates the Build Fontana Public Portal (Accela) for ADU intake plus a published Standard ADU Plans gallery satisfying AB 1332. STR use of the ADU is locally prohibited.
Cost scenarios
| Scenario | Sq ft | Permit | Build | Total |
|---|---|---|---|---|
| minimum | 400 | $4,800 | $196,000 | $200,800 |
| 600 | 600 | $6,800 | $282,000 | $288,800 |
| midpoint | 700 | $7,900 | $329,000 | $336,900 |
| 1000 | 1,000 | $13,200 | $480,000 | $493,200 |
| maximum | 1,200 | $15,800 | $576,000 | $591,800 |
Fee breakdown (as of 2026-04)
Permitting process
- Determine track: Standard ADU plan vs custom (~3d)
Browse the Fontana Standard ADU Plans gallery at fontanaca.gov/3710/Standard-ADU-Plans for designer pre-approved plans. Plans still require site-specific information and permit approval. Custom designs follow the standard plan-review track. - Submit application via Build Fontana Public Portal (Accela) (~1d)
Submit ADU application via the Build Fontana Public Portal at aca-prod.accela.com/FONTANA. Building & Safety encourages online submittal of applications and download of plans through the portal. Counter intake also accepted at 8353 Sierra Avenue. - Initial completeness check (~15d)
Fontana Planning confirms application completeness. City has implemented a 15-day approval target for ADU/JADU applications for code-compliant submittals. - First plan review (Building, Planning, San Bernardino County Fire, MEP) (~21d)
Concurrent review across Building & Safety, Planning (zoning clearance under Section 30-467), San Bernardino County Fire (which provides fire services to Fontana), and MEP. Counter hours Mon-Thu 8am-5pm; office hours 7am-6pm. - Subsequent plan-review cycles (~14d)
Corrections cycle; one or two cycles typical for non-Standard-Plan designs. - Permit issuance (~5d)
Fees paid; permit downloaded via Build Fontana Portal. Total ministerial limit is 60 days from complete submittal per state law. - Construction inspections
Foundation, framing, MEP rough, insulation, drywall, final. Inspection requests through the Build Fontana Portal. - Certificate of occupancy (~5d)
Final inspection pass triggers CO; ADU eligible for occupancy and long-term rental (STR explicitly prohibited under Section 30-467).
Viability (permitted uses)
- Long-term rental: yes (California Government Code 65852.2(a)(7)) 30+day rental of ADU explicitly permitted; AB 976 owner-occupancy preemption (2024-01-01) makes ADU eligible as a conventional rental. AB 1482 statewide rent cap (5% + CPI, max 10%) may apply to multifamily-zoned conversions.
- Short-term rental: no (Fontana Municipal Code Section 30-467) ADUs and JADUs are explicitly banned from short-term rental services (Airbnb / VRBO) in Fontana per Section 30-467. Long-term-only revenue model.
- Office rental: no Section 30-467 limits ADUs to dwelling-unit use; commercial office tenancy not permitted in residentially-zoned ADU.
- Home office: yes Home occupation permit available citywide; signage and customer-traffic limits apply.
- Studio / workshop: yes Personal artist/workshop use is a permitted accessory residential use.
- Agriculture: with-restrictions Limited urban agriculture in residential zones; ADU itself remains residential. Adjacent agricultural use governed by Right-to-Farm provisions.
- Relative support: yes Family-occupancy ADU explicitly permitted; JADU (under 500 sqft) specifically designed for owner+relative arrangement.
Incentives
- CalHFA ADU Grant Program — $40,000 one-time (when funded) (Income-qualified Fontana homeowners; reimburses pre-construction soft costs)
- Fontana Standard ADU Plans (AB 1332 implementation) — City-published gallery of designer-prepared pre-approved ADU plans with designer contact info; site-specific permit approval still required.
- SB 13 Impact Fee Waiver (under 750 sqft) — California state law prohibits impact, capacity, or connection fees on ADUs under 750 sqft.
Pre-approved plans Fontana Standard ADU Plans (AB 1332 implementation) · saves ~3 weeks
Contacts
Staff: Planning Department (Planning - ADU Plan Check and Development Impact Fees), Planning - Spanish Language (Planning Department (Spanish)), Building & Safety Department (Building & Safety - permits / inspections)
Contractor directory (5)
Utilities
- Water: Fontana Water Company (primary; one of five water providers serving defined Fontana service areas - blended local-basin groundwater + surface water) · 30d connect · $4,500
- Sewer: Inland Empire Utilities Agency (IEUA) regional treatment + City of Fontana sewer collection · 30d connect · $4,800
- Electric: Southern California Edison (SCE) · 45d connect · $2,400
- Gas: Southern California Gas Company (SoCalGas) · 30d connect · $1,700
Property values & taxes
Market rent by ADU size
| Sq ft | Rent |
|---|---|
| 400 | $1,550/mo |
| 600 | $1,925/mo |
| 800 | $2,300/mo |
| 1,000 | $2,575/mo |
Construction timeline
Realistic total: best 7mo · typical 11mo · worst 18mo
Inland Empire GC market is broad due to volume of warehouse and SFR construction; modular ADU pathway is mature (USModular factory in nearby Lake Elsinore). Lytle Creek alluvial-fan parcels in north Fontana need geotech evaluation; SCAQMD non-attainment dust-control rules apply during construction.
Modular pathway California HCD Factory-Built Housing Program · inspectors are experienced with modular
Inland Empire access via I-10, I-15, SR-210; warehouse-corridor lane closures occasional; older Fontana foothill streets narrower than newer master-planned subdivisions in Hunters Ridge / Sierra Lakes.
Financing
State ADU loans:
- CalHFA ADU Grant Program (California Housing Finance Agency) up to $40,000
- HCD ADU Funding Resources Index (California Department of Housing and Community Development)
Insurance impact
California-wide insurer pullback affects rate quotes; Fontana foothill parcels in CAL FIRE FHSZ zones carry materially higher premiums and may require California FAIR Plan. SCAQMD air-quality findings are insurance-neutral but health-disclosure relevant.
HOA prevalence & preemption
Fontana has substantial master-planned HOA neighborhoods (Hunters Ridge, Citrus Heights, Sierra Lakes, Heritage, Empire Center area); state law voids HOA covenants prohibiting ADUs but reasonable design standards remain enforceable.
Regulatory overlays (3)
- flood-zone — FEMA SFHA along Lytle Creek Wash (north Fontana) and San Sevaine Channel; portions of west Fontana intersect Etiwanda / Day Creek wash networks. · +14d · +5% cost
Elevation certificates and flood-resistant construction required for SFHA parcels; Lytle Creek alluvial-fan deposit history requires geotech soils review. (map) - wui-fire-zone — Northern Fontana foothill parcels approaching San Bernardino National Forest may carry CAL FIRE FHSZ designation; central/south Fontana on the alluvial fan typically does not. · +14d · +6% cost
Where applicable, CBC Chapter 7A wildfire-rated assemblies required: Class A roof, ember-resistant vents, ignition-resistant siding. (map) - other — South Coast Air Quality Management District (SCAQMD) extreme non-attainment for ozone and PM2.5 covering all of Fontana; warehouse-corridor air-quality concerns implicated by 2024 California AG settlement. · +2% cost
Construction dust-control (Rule 403) applies to all building sites; warehouse-adjacent residential parcels gained additional CEQA protections under the 2024 AG/Fontana settlement. (map)
Technical envelope (climate & building code)
Climate & energy code
Building code
Amendments:
- Fontana Local Building Code Amendments — Local amendments addressing Lytle Creek alluvial-fan soils, Santa Ana wind exposure, and SCAQMD construction-dust rules.
Contractor market (aggregate)
Legal history (timeline)
Current ordinance: Fontana Municipal Code Section 30-467 - Accessory Dwelling Units, adopted 2017-01-01, last amended 2024-01-01
- 2017-01-01 — California SB 1069 / AB 2299 - statewide ADU streamlining (state-law)
California's first comprehensive overhaul of state ADU law, mandating ministerial review and reducing local barriers.
Effect: Triggered Fontana's 2017 cycle of Section 30-467 amendments to align with the statewide ADU framework. - 2020-01-01 — California AB 68 / AB 881 / SB 13 / AB 670 - 2020 ADU package (state-law)
California's 2020 ADU package mandating one ADU + one JADU per single-family lot, 60-day ministerial review, sub-750 sqft fee waiver, and HOA-covenant preemption.
Effect: Drove Fontana Planning Commission action to align Section 30-467 with state law (Fontana Herald News reporting). - 2024-01-01 — California AB 976 - Permanent prohibition on owner-occupancy (state-law)
Permanently bars California cities from imposing owner-occupancy as a condition of ADU permitting.
Effect: Removed any remaining owner-occupancy condition in Fontana Section 30-467; JADUs under 500 sqft retain a separate state-law owner-occupancy requirement. - 2024-09-23 — California AG / City of Fontana settlement on warehouse-development environmental review (other)
Attorney General Bonta announced an innovative settlement with the City of Fontana addressing environmental injustices in warehouse development; settlement constrains future warehouse approvals near sensitive land uses.
Effect: Indirectly affects ADU lots near logistics corridors: heightened CEQA / SCAQMD-burden review may push warehouse projects further from residential, but residential-adjacent parcels gain stronger environmental-review protections. - 2025-01-01 — California AB 1332 - Mandatory preapproved-ADU-plans program (state-law)
Requires every California local agency to develop a program for preapproved ADU plans by 2025-01-01.
Effect: Fontana's Standard ADU Plans gallery (designer pre-approved plans linked at fontanaca.gov/3710) satisfies the AB 1332 requirement; site-specific permit approval is still required.
Known issues (1)
- policy-review (since 2024-09) — Sept 2024 settlement constrains future warehouse approvals near sensitive land uses (schools, daycares, residential). Affects ADU lots near logistics corridors via heightened CEQA / SCAQMD-burden review, generally favoring residential areas. (source)
San Bernardino County — county ADU rules and overlays
County ADU ordinance
California state — ADU law and programs
State ADU law
California has the most aggressive statewide ADU preemption regime in the US, built from ~15 bills passed 2019-2025 and enforced by the Department of Housing and Community Development (HCD). The 2026 HCD ADU Handbook addendum (in effect with the 2025 Title 24 code cycle) is the operative state-level reference. The regime does four things at once: (1) preempts local zoning that would ban or unreasonably restrict ADUs; (2) imposes by-right ministerial approval with short statutory deadlines; (3) caps fees and utility-connection charges; and (4) empowers HCD to void non-compliant local ordinances.
State HOA preemption
California has the strongest statewide HOA-preemption regime in the US for accessory dwelling units, built from two bills: AB 670 (2019) voided ADU-prohibiting covenants on single-family residential lots, and AB 3182 (2020) extended and codified the preemption into the Davis-Stirling Common Interest Development Act (Civil Code §§ 4740 / 4741). The combination prohibits common-interest communities from banning ADUs, restricting rentals below 25% of separate interests, or treating ADUs as separate HOA interests. Limits remain: HOAs retain authority over reasonable design standards and statutory height limits, and the 2026 Carlsbad case (CalMatters coverage) established that an HOA's documented design-standards regime can effectively delay or constrain ADU approval short of outright prohibition.
State financing programs
California's flagship state-level ADU financing program — the CalHFA ADU Grant Program — is paused and has not been refunded since the original $100 million allocation was fully deployed 2023-12-28. The program provided up to $40,000 per qualifying homeowner for pre-construction and non-recurring closing costs and financed approximately 2,500 ADUs in two rounds. As of 2026-04, no new funding round has been announced in the state budget. CalHFA continues to publish anti-scam warnings because bad actors actively solicit homeowners claiming access to grant funds that no longer exist. State-level financing activity has shifted to local pilot programs (San Francisco, San Jose, Los Angeles, San Diego) and private financing products (Fannie Mae ADU mortgage, HELOC, construction-to-permanent).
State housing programs
California's state-level ADU programs are concentrated at HCD (technical guidance, ordinance review, enforcement) and the paused CalHFA grant pipeline (covered under stateFinancing). The state does not operate a central pre-approved ADU plan library — instead, AB 1332 (2024) created a preemption framework for local pre-approved plans with a 30-day ministerial-approval deadline, and major cities (Los Angeles, San Diego, San Jose, Sacramento, Berkeley) have rolled out their own plan catalogs. The California YIMBY coalition and other housing-policy organizations play an influential role in bill drafting; they are not state agencies but effectively drive much of the ADU legislative agenda. The Title 24 code cycle (now 2025, in effect for 2026 permits) is the authoritative building-code baseline.
Federal (United States) — ADU-relevant rules and programs
Federal ADU law
The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.
Federal financing programs
Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.
Federal tax credits
There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.
Federal housing programs
HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.
ZIP Codes
- 92335
- 92336
- 92337
Post Office
- 16731 Santa Ana Ave, 92337
- 8282 Sierra Ave, 92335
Locale Names
- Southside