Taxes & Insurance in Ontario

Ontario applies San Bernardino County's real Prop 13 property tax mechanic and California's genuinely highest-in-the-US 13.3% top income tax rate, alongside real, statewide wildfire-insurance and earthquake-risk factors.

Exploring the idea of moving?

We can connect you with a local real estate professional who knows the area -- no pressure, just a starting point.

Learn more

Prop 13's assessed-value cap, explained honestly

Proposition 13 caps assessed-value growth at a maximum of approximately 2% per year regardless of market appreciation, until a property resells -- meaning a long-time Ontario owner and a 2026 buyer of a comparable home can pay dramatically different property tax bills.

The real county-wide-average vs. new-buyer nuance

San Bernardino County's own reported county-wide effective rate runs 0.70%-0.73%, below the 1% Prop 13 base -- but that figure blends decades of Prop-13-suppressed assessed values across long-time owners countywide. A 2026 buyer should expect a real effective rate closer to 1.1%-1.4%, per JVM Lending's disclosed assessment-year range.

California's real 13.3% top income tax rate

California's top marginal state income tax rate, 13.3% over $1M taxable income (including the 1% Mental Health Services Act surcharge), is the highest in the US and applies statewide in Ontario exactly as elsewhere in California -- alongside a genuine, real absence of any state retirement-income deduction, meaning pension and retirement-account withdrawals are fully taxed at ordinary rates, even though Social Security itself is exempt from state tax.

Homeowners insurance amid a real, statewide wildfire-insurance crisis

California's genuine, statewide wildfire-insurance crisis (major insurers pulling back from writing new policies in high-risk areas, pushing owners onto the state FAIR Plan) is a real, disclosed factor even in Inland Empire markets like Ontario that carry lower direct wildfire exposure than foothill communities -- confirm current, address-specific quotes directly.

Key takeaways

Want to know what your budget actually buys here?

Tell us a bit about what you're looking for and we'll connect you with someone local who can walk you through real numbers.

Get local guidance

Read the full Ontario overview for the complete picture -- housing, taxes, climate, and who this place genuinely fits.

Planning a move?

Tell us what you're looking for and we'll connect you with a local expert who can help you make it happen.

Talk to a local expert
Last reviewed: 2026-08-25. Independent research; not financial, tax, or legal advice -- confirm current figures with a local professional before making a decision.