Quick Answer
California property tax starts at a 1% base rate on assessed value (set by Proposition 13), with annual increases capped at 2% until a change of ownership triggers reassessment at current market value. The actual effective rate ranges from 1.10% to 1.55%+ depending on your county, voter-approved bonds, and Mello-Roos assessments. On a $800,000 home in Los Angeles County, expect to pay roughly $9,100–$10,700 per year.
Key Takeaways
- Prop 13 base rate: 1% of assessed value, capped at 2% annual increases
- Effective rates: 1.10%–1.55%+ when bonds and Mello-Roos are included
- Prop 19 (2021): Changed inheritance rules—children must live in inherited home within 1 year
- Mello-Roos: $360–$10,000+/year in newer communities, not based on property value
- Supplemental tax: A surprise bill 3–9 months after buying—not covered by escrow
- Homeowner's exemption: $7,000 reduction (saves ~$70/year)—file BOE-266 once
- Appeals succeed 30–38% of the time when you have comparable sales evidence
- Payment deadlines: December 10 (1st installment) and April 10 (2nd installment)
Why Trust This Guide? | Last Verified: February 1, 2026
- Primary sources: California Board of Equalization (BOE) Letters to Assessors, BOE Publication 29, all 58 County Assessor offices
- Data verified: Prop 19 exclusion amount ($1,044,586) confirmed via BOE Letter 2025/009; Disabled Veteran amounts via BOE Letter 2025/014
- Updated for 2026: Includes AB 245 disaster relief, Measure ULA thresholds (effective July 2025), and current FBYV adjustment periods
- Cross-referenced: Legislative Analyst's Office reports, SmartAsset county data, JDJ Consulting rate analysis
What's in This Guide
- Proposition 13: The Foundation
- How Your Property Tax Is Calculated
- County-by-County Tax Rates
- Proposition 19: Inheritance & Senior Transfers
- Mello-Roos & Community Facilities Districts
- Supplemental Property Tax
- Transfer Taxes (Documentary & City)
- Exemptions & Tax Reductions
- How to Appeal Your Assessment
- New Construction & Improvements
- Payment Calendar & Deadlines
- Frequently Asked Questions
You've probably heard that California property taxes are "locked in."
And while that's mostly true, there's a catch. Between new inheritance laws, "surprise" supplemental bills, and Mello-Roos districts, your "1% rate" can quickly turn into 1.5% or more.
Here's the deal:
Most states reassess your home's value every single year. California doesn't. Thanks to Proposition 13, your tax is based on what you paid for the home—not what it's worth today.
But if you aren't careful, you could end up blindsided by a tax bill that doesn't fit your budget. New buyers regularly get hit with supplemental bills arriving months after closing. Heirs discover their parents' low tax base doesn't transfer the way it used to. And homeowners in newer communities pay thousands more than neighbors down the street because of Mello-Roos.
In this guide, I'll break down exactly how the system works in 2026—including the "hidden" taxes most buyers miss.
California Property Tax by the Numbers
- $7.8 trillion in net statewide assessed value (2021–22)
- $85+ billion in annual property tax revenue
- 53% allocated to K-12 schools and community colleges
- 58 counties with varying effective tax rates
- 1978: Proposition 13 passed with 65% voter approval
Proposition 13: The Foundation of California Property Tax
What Is Proposition 13?
Passed in June 1978, Proposition 13 moved California to an acquisition-value system. Your property tax is based on what you paid for your home—not what it's worth today.
Think about it: If you bought a house in 1995 for $200,000, your taxes are still based on that $200,000 (plus a tiny annual inflation adjustment). Your neighbor who bought the identical house last week for $1.5 million? They're paying nearly 8 times more in property tax than you are.
Before Prop 13, the average California property tax rate was 2.67%. Rapid appreciation in the 1970s meant annual bills could spike dramatically, pushing retirees out of their homes. After passage, property tax revenues dropped from $10.3 billion to $5.04 billion—a 51% cut overnight.
The Three Pillars of Prop 13
Here's how it works:
| Pillar | Rule | Details |
|---|---|---|
| 1% Tax Cap | Maximum ad valorem rate | The base rate on assessed value; collected by counties and distributed to local districts |
| 2% Annual Cap | Assessment increase limit | Limited to 2% OR California CPI, whichever is lower |
| Reassessment Triggers | Change of ownership or new construction | Full market value reassessment only when property changes hands or is substantially improved |
Base Year Value: How It Works
When you buy a home, the purchase price becomes your "base year value". Each year, the assessor increases this value by the inflation factor (max 2%), creating your Factored Base Year Value (FBYV).
Key concept: The FBYV is the ceiling on your assessed value. If you bought a home for $500,000 in 2015, your assessed value in 2026 is roughly $610,000—even if the home is now worth $900,000. You're taxed on $610,000.
What Triggers a Reassessment?
Change of ownership events that trigger full reassessment:
- Sales or purchases of real property
- Gifts and inheritances (subject to Prop 19 rules)
- Adding or removing an owner from the title
- Transfers by deed, trust, or contract of sale
- Legal entity rule: When a person or entity obtains more than 50% ownership in an LLC, partnership, or corporation that holds real property
Exceptions to the 1% Cap
The 1% limitation does not apply to:
- Bonded debt approved by voters before July 1, 1978
- Bonded debt for property acquisition/improvement approved by two-thirds majority after 1978
- School facility bonds approved by 55% of voters (Proposition 39, 2000)
This is why your actual tax rate is always higher than 1%—the additional 0.10%–0.55% comes from voter-approved bonds in your area.
How Your California Property Tax Is Calculated
Answer
California property tax equals 1% of assessed value (your purchase price, not market value) plus voter-approved bonds (0.10%–0.55%) plus any Mello-Roos/CFD assessments. On an $800,000 home in Los Angeles County, expect to pay approximately $9,100–$10,700 per year (effective rate: 1.15%–1.35%).
Here's what that looks like in practice:
Take an $800,000 home in Los Angeles County. Your tax bill breaks down like this:
| Component | Calculation | Amount |
|---|---|---|
| Base Tax (1%) | $800,000 × 1.00% | $8,000 |
| Voter-Approved Bonds | $800,000 × 0.15% | $1,200 |
| Homeowner's Exemption | $7,000 × 1.15% | -$80.50 |
| Subtotal (Ad Valorem) | $9,119.50 | |
| Mello-Roos (if applicable) | Fixed assessment | $1,500 |
| Lighting/Flood Districts | Fixed assessments | $110 |
| Total Annual Tax | $10,729.50 |
Effective rate: $10,729.50 ÷ $800,000 = 1.34%
First-Year Buyer Checklist
- Look up your property on the county tax collector website
- Identify all Mello-Roos and special assessments on the bill
- Calculate your effective tax rate (total tax ÷ purchase price)
- Budget for supplemental taxes (arrives 3–9 months after closing)
- File the Homeowner's Exemption (BOE-266) by February 15
County-by-County Tax Rates (2025–2026)
Answer
California effective property tax rates range from 1.10% to 1.55%+ depending on county. Lowest: San Diego and San Bernardino (~1.10%). Highest: Riverside, Sacramento, and Orange County (up to 1.55%+ in Mello-Roos areas). Los Angeles averages 1.15%–1.35%. All counties start with the 1% Prop 13 base; the variation comes from voter-approved bonds and special assessments.
The base rate is always 1%, but voter-approved bonds and special assessments push the effective rate higher.
Here's how the major counties stack up:
| County | Base Rate | Bonds | Effective Range | Median Home Value | Est. Annual Tax |
|---|---|---|---|---|---|
| Los Angeles | 1.00% | 0.15–0.35% | 1.15–1.35% | $866,500 | $10,625 |
| Santa Clara | 1.00% | 0.20–0.40% | 1.20–1.60% | $1,555,600 | $15,120 |
| Orange | 1.00% | 0.10–0.25% | 1.10–1.55%* | $1,037,200 | $11,400 |
| San Diego | 1.00% | 0.10–0.20% | 1.10–1.25% | $914,700 | $9,440 |
| San Francisco | 1.00% | 0.15–0.25% | 1.15–1.25% | $1,300,000 | $15,600 |
| Alameda | 1.00% | 0.15–0.30% | 1.15–1.35% | $1,090,600 | N/A |
| Sacramento | 1.00% | 0.15–0.35% | 1.15–1.55%* | $570,000 | $7,296 |
| Riverside | 1.00% | 0.15–0.55%+ | 1.15–1.55%+ | $601,600 | $4,526 |
| San Bernardino | 1.00% | 0.10–0.25% | 1.10–1.30% | $545,900 | N/A |
| Fresno | 1.00% | 0.15–0.30% | 1.15–1.30% | $450,000 | $5,850 |
*Higher ranges indicate areas with active Mello-Roos/CFD assessments. Sources: County Assessor offices, SmartAsset, JDJ Consulting (2025 data).
Proposition 19: Inheritance Rules & Senior Transfers
Answer
Proposition 19 (effective February 16, 2021) restricts inherited property tax exclusions to primary residences only—the child must move in within 1 year and file the Homeowner's Exemption. Investment properties no longer qualify. However, Prop 19 expanded senior benefits: homeowners 55+ can now transfer their tax base anywhere in California, up to 3 times, and can buy a more expensive replacement home.
Proposition 19 (effective February 2021) is the biggest shake-up since the '70s. It affects two groups: heirs inheriting property and seniors moving homes.
Here's the kicker:
You can no longer inherit your parents' low tax base for a vacation home or a rental property. To keep their rate, the home must become your primary residence.
Critical Prop 19 Warning
44% of Prop 19 applications are denied statewide. The most common reasons: missing the 1-year residency deadline, failing to file the Homeowner's Exemption (BOE-266), or inheriting non-primary-residence property (investment properties no longer qualify for exclusion).
What Changed from the Old Rules (Prop 58/193)
The differences are stark:
| Feature | Old Rules (Prop 58/193) | New Rules (Prop 19) |
|---|---|---|
| Parent-to-child primary residence | Unlimited value, any use | Principal residence only, value cap |
| Parent-to-child other property | $1M assessed value per parent | Eliminated |
| Child residency requirement | None | Must move in within 1 year |
| Senior base transfer location | 10 participating counties only | All 58 counties |
| Senior transfer frequency | Once in lifetime | Up to 3 times |
| Senior replacement value | Equal or lesser value only | Any value (with adjustment) |
Parent-to-Child Transfer Rules (Since February 16, 2021)
For an inherited home to keep the parent's low tax base, all four of these must be true:
- The property was the transferor's principal residence
- The child moves in within 1 year of transfer
- The child files the Homeowner's Exemption (BOE-266) within 1 year
- The child continues to use it as their primary residence
If the child moves out, the property is reassessed at fair market value.
The Value Test: Partial Reassessment
Even when all residency requirements are met, Prop 19 may trigger a partial reassessment if the home has appreciated significantly:
| Property Metric | Case A (Below Cap) | Case B (Above Cap) |
|---|---|---|
| Parent's FBYV | $400,000 | $400,000 |
| Prop 19 Adjustment (2025–27) | $1,044,586 | $1,044,586 |
| Excluded Amount (Sum) | $1,444,586 | $1,444,586 |
| Fair Market Value at Transfer | $1,200,000 | $2,000,000 |
| Excess Over Excluded Amount | $0 | $555,414 |
| Child's New Tax Base | $400,000 (no change) | $955,414 (partial reassessment) |
The Prop 19 $1 million adjustment is indexed for inflation every two years:
| Transfer Period | Adjusted Amount |
|---|---|
| Feb 16, 2021 – Feb 15, 2023 | $1,000,000 |
| Feb 16, 2023 – Feb 15, 2025 | $1,022,600 |
| Feb 16, 2025 – Feb 15, 2027 | $1,044,586 (current period) |
Source: BOE Letter to Assessors No. 2025/009 (March 2025). The Prop 19 exclusion amount of $1,044,586 applies only to transfers occurring between February 16, 2025 and February 15, 2027.
Prop 19 Filing Requirements
| Form | Purpose | Deadline |
|---|---|---|
| BOE-19-P | Parent-child transfer exclusion | Within 3 years of transfer |
| BOE-19-G | Grandparent-grandchild transfer | Within 3 years of transfer |
| BOE-19-B | Base year transfer (55+) | Within 3 years of replacement purchase |
| BOE-266 | Homeowner's exemption | Within 1 year of transfer (critical!) |
Senior Base Year Value Transfer (55+ Homeowners)
Prop 19 significantly expanded benefits for homeowners age 55+, severely disabled, or disaster victims:
- Transfer your tax base anywhere in California (all 58 counties)
- Use up to 3 times in your lifetime (unlimited for disaster victims)
- Buy a more expensive replacement home (with adjustment for the difference)
- Complete the move within 2 years of sale
| Timing | Equal/Lesser Value Threshold |
|---|---|
| Purchase replacement before selling original | 100% of original's market value |
| Purchase within 1st year after sale | 105% of original's market value |
| Purchase within 2nd year after sale | 110% of original's market value |
Strategy: If buying up, the difference in market value gets added to your transferred base. Example: You sell a home worth $600,000 (FBYV: $200,000) and buy a $900,000 replacement. Your new tax base = $200,000 + $300,000 = $500,000—still saving significantly compared to a full $900,000 assessment.
Mello-Roos & Community Facilities Districts (CFDs)
What Is Mello-Roos?
The Mello-Roos Community Facilities Act of 1982 lets local governments create Community Facilities Districts (CFDs) to fund infrastructure—new schools, fire stations, and road improvements—by issuing tax-exempt bonds. Named after Senator Henry Mello and Assemblyman Mike Roos.
Here's the problem:
Mello-Roos assessments are not based on your home's value. They're calculated by square footage, lot size, or a flat rate—and they're not subject to Prop 13 limits. That $2,000/year Mello-Roos fee stays the same whether your home is worth $500,000 or $2 million. And unlike the 1% base tax, Mello-Roos is generally not tax-deductible.
Typical Mello-Roos Amounts
The range is wild:
| Level | Annual Amount | Monthly Equivalent |
|---|---|---|
| Low | $360–$1,500 | $30–$125 |
| Typical | $2,000–$4,000 | $165–$335 |
| High | $6,000–$10,000+ | $500–$835+ |
Real examples:
- Lincoln Crossing (Placer County): $1,184–$3,679 based on square footage
- Valencia/Santa Clarita: $1,510–$4,000
- Irvine (Great Park): $6,400–$7,000+
Where Mello-Roos Is Most Common
If you're shopping in these areas, assume Mello-Roos applies:
- Orange County: Irvine (most areas post-1988), Great Park, Ladera Ranch, Aliso Viejo, Rancho Santa Margarita, Coto de Caza
- San Diego County: Santaluz, Black Mountain Ranch, Carlsbad, Chula Vista
- Inland Empire: Highest concentration in California—Riverside County new developments
- Sacramento Region: El Dorado Hills, Lincoln Crossing, Folsom
Mello-Roos Rule of Thumb
- Homes built before 1990: Unlikely to have Mello-Roos
- Homes built after 2000: Very likely to have Mello-Roos
- Typical bond duration: 20–25 years (max 40 years by law)
- Some CFDs allow prepayment—contact the administrator for calculation
How to Research Mello-Roos Before Buying
- Use the county tax collector website to look up the property by APN (Assessor's Parcel Number)
- Review the preliminary title report for recorded CFD liens
- Request the seller's Notice of Special Tax disclosure
- Contact the CFD administrator (phone number appears on the tax bill)
Questions to ask before buying: How many CFDs apply to this property? What are the current and maximum annual amounts? When does the bond expire? Is there an early payoff option?
Mello-Roos assessments also impact mortgage eligibility—lenders include these costs in your debt-to-income (DTI) ratio, which can reduce your borrowing power.
Mello-Roos Delinquency Warning
Mello-Roos has an accelerated foreclosure timeline. The county can begin foreclosure proceedings just 90–150 days after delinquency—much faster than standard property tax delinquency.
Supplemental Property Tax: The Surprise Bill
Answer
A supplemental property tax bill is a one-time charge issued 3–9 months after closing that covers the difference between the prior owner's assessed value and your purchase price for the remainder of the fiscal year. Supplemental taxes are NOT covered by your mortgage escrow—you must pay them directly. Budget 0.75%–1.25% of the purchase price increase. If you close between January and May, expect two supplemental bills.
This one blindsides new buyers every single time.
When you buy a home, the county takes a few months to update their records. In the meantime, you're paying based on the old owner's assessed value.
But wait—there's more.
A few months later, the county sends a "Supplemental Bill" to collect the difference between the old price and your new purchase price. This shows up 3–9 months after closing, completely out of the blue.
How Supplemental Tax Is Calculated
Formula:
Supplemental Tax = (New Value − Prior Assessed Value) × Tax Rate × Proration Factor
Monthly Proration Factors
| Event Month | Remaining Months | Factor |
|---|---|---|
| July | 11 | 0.92 |
| August | 10 | 0.83 |
| September | 9 | 0.75 |
| October | 8 | 0.67 |
| November | 7 | 0.58 |
| December | 6 | 0.50 |
| January | 5 | 0.42 |
| February | 4 | 0.33 |
| March | 3 | 0.25 |
| April | 2 | 0.17 |
| May | 1 | 0.08 |
| June | 0 | 1.00 (rolls to next year) |
Worked Example: March Closing
Supplemental Tax Calculation
- Purchase price: $800,000
- Prior assessed value: $500,000
- Tax rate: 1.15%
- Closing month: March (factor: 0.25)
- Bill #1 (current year): ($300,000 × 1.15% × 0.25) = $862.50
- Bill #2 (next full year): ($300,000 × 1.15% × 1.00) = $3,450
- Total supplemental liability: $4,312.50
And it gets worse if you close early in the year:
Close between January 1 and May 31? You'll receive two supplemental bills—one prorated for the current fiscal year and one for the full next fiscal year. Double the surprise, double the budget hit.
Supplemental Tax is NOT Covered by Escrow
Your mortgage company's escrow account will not pay supplemental tax bills. These arrive 3–9 months after closing and are your sole responsibility.
Budget 0.75%–1.25% of the purchase price increase for supplemental taxes in your first year.
Transfer Taxes: What You Pay When Buying or Selling
Answer
California transfer taxes are one-time fees paid at closing. The statewide county rate is $1.10 per $1,000 (0.11%). City transfer taxes vary dramatically: San Francisco charges up to 6.00% on properties over $25M, Los Angeles charges up to 5.5% on properties over $10.6M (Measure ULA "mansion tax"), and Oakland up to 2.61%. Many smaller cities have no additional transfer tax.
Transfer taxes are one-time fees paid at closing. California has both county and city transfer taxes.
And the city rates? They vary wildly.
Standard County Transfer Tax
The statewide county rate is $1.10 per $1,000 of sale price (0.11%). This applies to every property sale in California.
City Transfer Taxes: Where It Gets Expensive
San Francisco (tiered system):
| Property Value | Effective Rate |
|---|---|
| $100–$250,000 | 0.50% |
| $250,001–$999,999 | 0.68% |
| $1,000,000–$4,999,999 | 0.75% |
| $5,000,000–$9,999,999 | 2.25% |
| $10,000,000–$24,999,999 | 5.50% |
| $25,000,000+ | 6.00% |
Los Angeles — Measure ULA ("Mansion Tax"), effective April 1, 2023:
| Property Value | ULA Rate | Total Effective Rate |
|---|---|---|
| Up to $5,300,000 | 0% | 0.56% |
| $5,300,001–$10,599,999 | 4.0% | 4.56% |
| $10,600,000+ | 5.5% | 6.06% |
ULA thresholds effective July 1, 2025 — adjusted annually for CPI. Verify current thresholds at finance.lacity.gov before closing.
Other notable city rates:
- Oakland: Tiered from 1.11% (under $300K) to 2.61% (over $5M)
- Santa Monica: Up to 5.71% (over $8M)
- San Jose: Up to 1.94% (over $10M)
- Sacramento: 0.385% ($2.75 city + $1.10 county)
- Berkeley (effective January 2027): Tiered from 1.5% to 3.5% (over $3M)
Exemptions & Tax Reductions
Answer
California property tax exemptions include: Homeowner's Exemption ($7,000 reduction, saves ~$70/year—file BOE-266 once); Disabled Veteran Exemption ($180,671–$271,009 reduction for 100% disabled veterans); Property Tax Postponement (deferral for seniors 62+); Mills Act (20–70% savings for historic properties); and Active Solar Exclusion (solar systems excluded from reassessment until 2027).
Homeowner's Exemption
This is the easiest money you'll ever save. File BOE-266 once (takes 5 minutes), and you get a $7,000 reduction in assessed value—saving roughly $70/year forever. No annual renewal needed.
Deadline: February 15 for the full exemption that tax year. File it the day you close.
Disabled Veteran Exemption (2026 Lien Date)
| Type | Assessed Value Reduction | Income Limit |
|---|---|---|
| Basic | $180,671 | None |
| Low-Income | $271,009 | $81,131 household income |
Requires 100% disability or unemployability from service-connected injury. File BOE-261-G with the county assessor. The low-income exemption requires annual filing.
Source: BOE Letter to Assessors No. 2025/014 (May 2025). Amounts are adjusted annually for inflation.
Property Tax Postponement Program
Property Tax Postponement (State Controller's Office)
- Eligibility: Seniors 62+, blind, or disabled
- Household income limit: $55,181
- Home equity requirement: Minimum 40%
- This is a LOAN at 5% simple interest—not an exemption
- Repaid when homeowner moves, sells, or passes away
Other Exemptions and Exclusions
| Exemption | Description | Potential Savings | Form/Notes |
|---|---|---|---|
| Mills Act | Historic property contract | 20–70% savings | Local application; 10-year minimum contract |
| Williamson Act | Agricultural land preservation | 20–75% savings | 10-year minimum contract |
| Active Solar | Solar systems excluded from reassessment | Varies | Automatic; sunsets January 1, 2027 |
| Seismic Retrofit | Earthquake improvements excluded | Varies | Notify assessor within 30 days of completion |
| Disabled Access | Accessibility modifications excluded | Varies | BOE-63 + physician certification |
| Fire Sprinkler | Fire safety systems excluded | Varies | Automatic for existing buildings |
| Disaster Reconstruction | Rebuild to equivalent condition | Restores prior base | 5-year window (8 years for 2025 fire victims per AB 245) |
How to Appeal Your Property Tax Assessment
Answer
California property tax appeals succeed 30–38% of the time. File BOE-305-AH with the Clerk of the Board before your county's deadline (September 15 in SF/Bay Area, December 1 in LA/San Diego/Orange). Best evidence: 3–6 comparable sales within 90 days after the January 1 lien date. Start with an informal review at the assessor's office first—many cases resolve without a formal hearing.
Think your home is over-assessed? You can fight it. And you've got decent odds: appeals succeed 30–38% of the time when you bring solid evidence.
Grounds for Appeal
- Decline in market value (Proposition 8)—current value has fallen below your factored base year value
- Factual errors—wrong square footage, lot size, or property features
- Assessment exceeds market value
- Incorrect base year value
Filing Deadlines by County
| County | Appeal Deadline |
|---|---|
| Los Angeles | December 1 |
| San Francisco | September 15 |
| San Diego | December 1 |
| Orange | December 1 |
| Santa Clara | September 15 |
| Alameda | September 15 |
| Sacramento | December 1 |
Supplemental assessment appeals: within 60 days of mailing date.
Step-by-Step Appeal Process
- Contact the assessor first for an informal review (recommended—many issues are resolved here)
- If unsatisfied, file BOE-305-AH (Application for Changed Assessment) with the Clerk of the Board
- Receive a hearing notice (at least 45 days before your hearing)
- Present your evidence at the hearing
- Receive the board's decision
Appeal Strategy Tips
- Best evidence: 3–6 comparable sales within 90 days after the January 1 lien date
- The board cannot consider sales more than 90 days after the lien date
- For owner-occupied single-family homes, the burden of proof rests on the assessor
- You must continue paying taxes during the appeal process
- The board can lower, raise, or maintain the assessment
Proposition 8 Temporary Reductions
When your home's current market value falls below your factored base year value, you can request a temporary reduction under Prop 8. This reduction lasts one year and is reviewed annually. If the market recovers, your Prop 13 value is reinstated. Many assessors automatically review properties during market downturns.
New Construction & Improvement Rules
Answer
California reassesses property when you add square footage, convert non-habitable to habitable space, or make substantial renovations. However, roof replacement, painting, flooring, new windows, and fixture replacement do NOT trigger reassessment. ADUs create a "blended assessment"—only the ADU is assessed at market value; your main home keeps its existing base. Solar systems are excluded from reassessment until January 1, 2027.
Not every improvement triggers a reassessment. The line between "new construction" and "maintenance" can save you thousands—or cost you thousands if you don't understand it.
What Triggers Reassessment
- Any increase in square footage
- Converting non-habitable to habitable space (garage to room, attic conversion)
- ADUs and accessory structures
- Major renovations changing floor plans or upgrading capacity
- Substantial rehabilitation making property "substantially equivalent to new"
What Does NOT Trigger Reassessment
- Roof replacement (including shake or tile)
- Painting (interior or exterior)
- Flooring, carpet, and wall coverings
- Replacing fixtures with similar quality
- Replacing doors and windows (even energy-efficient upgrades)
- Rewiring or replumbing without capacity upgrade
- Replacing fences, decks, and stairways
ADU Considerations
- ADUs are treated as new construction
- Only the ADU is assessed—your primary residence keeps its existing base
- Creates a "blended assessment" (old base + new ADU value)
- Typical ADU assessment: $130–$165/sq ft in many counties
- SB 1164 (2022): May allow a 10-year exclusion for ADUs completed 2025–2030
Exclusions from Reassessment
| Improvement | Requirement |
|---|---|
| Active solar systems | Automatic exclusion until change of ownership; sunsets January 1, 2027 |
| Seismic retrofitting | Notify assessor within 30 days; file documentation within 6 months |
| Disabled access modifications | File claim with physician certification |
| Fire safety systems | Automatic for existing buildings |
| Disaster reconstruction | Rebuild to substantially equivalent condition within 5 years (8 years for 2025 fire victims) |
Payment Calendar & Deadlines
Answer
California property taxes are paid in two installments: 1st installment due November 1 (delinquent December 10), 2nd installment due February 1 (delinquent April 10). Late payment triggers a 10% penalty. After June 30, the property becomes "tax-defaulted" with 1.5% monthly interest (18%/year). The fiscal year runs July 1 to June 30, with the January 1 lien date setting assessed values.
| Event | Date |
|---|---|
| Lien Date | January 1 |
| Fiscal Year Begins | July 1 |
| Bills Mailed | Late October |
| 1st Installment Due | November 1 |
| 1st Installment Delinquent | December 10, 5:00 PM |
| 2nd Installment Due | February 1 |
| 2nd Installment Delinquent | April 10, 5:00 PM |
| Fiscal Year Ends | June 30 |
If December 10 or April 10 falls on a weekend or holiday, the deadline extends to the next business day.
Penalties for Late Payment
| Situation | Penalty |
|---|---|
| After December 10 (1st installment) | 10% of installment amount |
| After April 10 (2nd installment) | 10% + $10–$40 cost fee |
| After June 30 (tax-defaulted) | $33–$36 redemption fee + 1.5%/month (18%/year) |
| Mello-Roos delinquency | Accelerated foreclosure: 90–150 days |
Tax Sale Timeline
- Years 1–5: Redemption period (penalties accrue at 1.5%/month)
- Year 5+: Property subject to "Power of Sale"
- No redemption period after sale in California
Escrow/Impound Accounts
- Required when loan-to-value exceeds 90% (down payment under 10%)
- Required for all FHA and VA loans
- Lenders may hold a 2-month cushion per RESPA
- Supplemental taxes are NOT covered by escrow—homeowner's responsibility
2025–2026 Legislative Updates
AB 245: Disaster Relief for 2025 Fire Victims
Governor Newsom signed Assembly Bill 245 as an urgency measure in October 2025, providing relief for property owners affected by the 2025 Palisades, Eaton, Hurst, Lidia, Sunset, or Woodley fires.
- Standard law (Section 70.5) gives owners 5 years to rebuild and restore the original base year value
- AB 245 extends this window by 3 additional years (8 years total) for 2025 fire victims
SB 23: Disabled Veteran Protections
Senate Bill 23 aims to codify a full property tax exemption for 100% disabled veterans through 2035, replacing fragmented local provisions with a stable statewide mandate.
Frequently Asked Questions
Bottom Line
California property tax sounds complicated. But the core concept is simple: you're taxed on what you paid, not what your home is worth today.
Everything else—Mello-Roos, supplemental bills, Prop 19—are just layers on top of that foundation.
The homeowners who save the most do four things:
They file their Homeowner's Exemption the day they close. They research Mello-Roos before making an offer. They budget for supplemental bills. And they appeal their assessment the moment the market dips.
Your 4-Step Property Tax Action Plan
- File your Homeowner's Exemption (BOE-266) — Takes 5 minutes, saves $70/year forever. Do it the day you close.
- Budget for supplemental taxes — Set aside 0.75%–1.25% of the difference between your purchase price and the prior assessed value.
- Check for Mello-Roos before buying — Look up the property on the county tax collector site. Newer communities (post-2000) almost always have it.
- Monitor your assessment annually — If your home's market value drops below the assessed value, request a Prop 8 decline-in-value review.
Use our California Mortgage Calculator to see how property taxes affect your monthly payment—with California-specific rates built in.
Related Calculators
Helpful Resources
- California First-Time Homebuyer Programs 2026 — 100+ assistance programs with income limits and stacking strategies
- CalHFA Down Payment Assistance Guide — Complete breakdown of Dream For All, MyHome, and other CalHFA programs
- California DPA Finder Tool — Find down payment assistance programs you qualify for based on income, location, and loan type
- BOE Publication 29 — California Board of Equalization official property tax overview
- Proposition 19 Official Guide — BOE guidance on inheritance and senior transfer rules
- Property Tax Postponement Program — State Controller's Office deferral program for seniors
Glossary of California Property Tax Terms
- FBYV (Factored Base Year Value)
- Your original purchase price adjusted annually by the inflation factor (max 2%). This is the ceiling on your assessed value under Prop 13.
- Ad Valorem Tax
- Tax based on the assessed value of property ("according to value"). The 1% base rate is ad valorem; Mello-Roos is not.
- Supplemental Assessment
- A one-time tax bill issued when property changes ownership or new construction is completed, covering the difference between old and new assessed values for the remainder of the fiscal year.
- Mello-Roos / CFD
- Community Facilities District assessment to fund infrastructure. A fixed amount not based on property value and not subject to Prop 13 limits.
- Prop 8 Decline
- A temporary reduction in assessed value when current market value falls below the factored base year value. Reviewed and adjusted annually.
- APN (Assessor's Parcel Number)
- A unique number assigned to each parcel of real property by the county assessor. Used to look up tax records online.
- Lien Date
- January 1 of each year. The date that establishes property ownership, condition, and value for the upcoming fiscal year's tax assessment.
About Jon Teera
Jon Teera is the Lead Developer and Founder of CalcLogix. He builds tools that help homebuyers and homeowners navigate California's complex property tax system—because understanding the rules shouldn't require a tax attorney.
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