Ontario, California Building Permit Guide

The City of Ontario Building Department issues building permits from City Hall, 303 East B Street, Ontario, CA 91764. Counter services and plan check are at (909) 395-2023 and inspectors at (909) 395-2362. The counter is open Monday to Thursday 7:30 AM to 5:30 PM and Friday 8:00 AM to 5:00 PM, but closes for staff meetings every Tuesday 7:30 to 9:00 am and the first Thursday of each month 8:00 to 10:00 am.

This guide covers the City of Ontario. The City’s fee tables for building, electrical, mechanical, plumbing and grading permits could not be read, and the readable pages do not say how to request an inspection; ask the permit technicians at 909-395-2023.

What requires a building permit in Ontario?

• Retaining walls over 2 ft., measured from the bottom of the footing to the top of the wall.
• Walls and fences over 3 feet high: concrete block walls, block pilasters, chain link, wrought iron and wood fences.
• New buildings and additions also need a third plan set with a site plan and all floor plans at permit issuance, for the county assessor’s office.

California builds on one statewide code, Title 24, whose 2025 edition took effect on 1 January 2026; the editions in effect when the application is submitted apply, and cities and counties may adopt local amendments only with findings filed with the state (new residential amendments are largely frozen until June 2031). Title 24 and local amendments

Symbium permits for solar and re-roofs

Since August 4th, 2025, contractors and homeowners can apply through the City’s Symbium portal for residential roof-mounted solar, energy storage systems under 38.4 kW and detached single-family re-roof permits.

Contractors are licensed statewide by the Contractors State License Board (Classes A, B, B-2 and C) for work of $1,000 or more or any permitted work; a city may also require a business licence or tax registration. Contractor licensing in California

Who handles permitting in Ontario?

How to get a building permit in Ontario

A building permit carries a validity period and can expire if work does not start or stalls between inspections; confirm the expiry with the Building Department on phased or delayed work. Permit validity in California

Ontario permit costs and fees

• Plan check: 80% of permit fees, charged at submittal.
• Minimum fee for any permit: $47.50. Dust control: $250.
• Earthquake fee (residential): 0.0001 x valuation.
• On-site sewer assessment: $6,955 per dwelling unit, subject to annual increase.
• Development impact fees are collected at permit issuance.
• Extensions: since January 3rd, 2024, the first extension of a plan check or permit is free; each further one is $150 for residential or $300 for commercial/industrial permits. Requests go by email to the building counter.

A plan check expires 12 months after the plan check fee is paid. A permit expires if work has not started within six months of issuance or stops for over six months.

School fees are paid directly to the district: Chaffey Joint Union High School 909-988-8511 x2511, Chino Unified 909-628-1201 x1207, Cucamonga School District 909-987-8942 x8238, Mountain View School District 909-947-2992, Ontario-Montclair School District 909-459-2500 x 10483.

Official Ontario permitting resources

These are the primary sources behind this guide. Codes, fee schedules and procedures change — confirm the position for your filing date.

• Ontario Building Department
• Building Department fees
• Building permit FAQs
• Residential re-roof and solar permits (Symbium)
• Electronic submittal requirements (PDF)
• Ontario Planning Department

Frequently asked questions

Does a fence need a permit in Ontario?

Yes, if it is over 3 feet high; that covers block walls, pilasters, chain link, wrought iron and wood fences.

Can I resubmit only the corrected sheets?

No. Ontario wants a full plan set with corrections marked, and only after every reviewing department has issued its corrections list.

What does a second permit extension cost in Ontario?

$150 for residential or $300 for commercial/industrial; the first extension is free.

Simplify Ontario permitting with Alliance Permitting

• Check the City’s submittal rules, fee schedule and outside clearances for your project before filing
• Assemble and upload the application, plans and supporting documents
• Follow the permit through review, issuance and every inspection to final

Alliance Permitting is a permit documentation and submission company in California. We prepare your paperwork, file it correctly and coordinate with the permitting authority through issuance. We are not a contractor and we do not perform licensed plan review or inspections; that work stays with your licensed team and the jurisdiction.

This guide is provided by Alliance Permitting for general information about Ontario permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.