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Updated 2025 Tax Year

Marin County
Property Tax Guide

Everything you need to know about property taxes in Marin County, CA. Rates, due dates, exemptions, and how it affects your monthly payment.

10 Official Sources
8 min read
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Quick Facts
Tax Rate
1.1%-1.3% of assessed value (1% base rate plus voter-approved bonds and assessments, varies by district)
1st Due
Nov 1
2nd Due
Feb 1
Exemptions
5+ Available
Section 1

How Property Tax Works

Marin County property taxes are the primary funding source for essential local services including public schools, fire protection, libraries, parks, and county government operations. Property taxes in Marin County are administered by the County Assessor-Recorder-County Clerk's office and collected by the County Treasurer-Tax Collector. The county operates under California's Proposition 13 framework, which limits the base property tax rate to approximately 1% of assessed value, with additional voter-approved debt service and special assessments added on top.

Effective property tax rates in Marin County typically range from 1.1% to 1.3% of assessed value, though rates vary significantly by location within the county due to different combinations of school districts, municipal bonds, and special taxing districts. Each property falls within a specific Tax Rate Area (TRA) that determines the exact combination of taxes owed. Properties in areas with Mello-Roos Community Facilities Districts or recent bond measures will have higher effective rates than the base 1% rate established by Proposition 13.

Section 2

What Makes Up Your Tax Bill

ComponentApproximate RateDescription
Base County Rate~1.0000%State-mandated base rate under Proposition 13
School District Bonds0.05% - 0.15%Voter-approved school facility bonds (varies by district)
Municipal Bonds0.02% - 0.08%City infrastructure and facility bonds
Special Districts0.01% - 0.05%Fire districts, library districts, parks districts
Mello-Roos CFD0.10% - 0.30%Community Facilities Districts (newer developments)
Total Effective Rate1.10% - 1.35%Varies by Tax Rate Area (TRA)

Rates shown are estimates for FY 2024-2025 and vary by specific Tax Rate Area. Each property's exact rate depends on its location within overlapping taxing jurisdictions. Marin County has over 200 different TRAs, each with a unique six-digit identifier and specific rate combination. Contact the Marin County Assessor-Recorder-County Clerk at (415) 473-7215 or visit marincounty.org to determine your property's specific TRA and current tax rate.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Marin County, property taxes are due in two installments:

First Installment
Nov 1
Delinquent after Dec 10
Second Installment
Feb 1
Delinquent after Apr 10
Pro tip: If you pay through mortgage escrow, your lender splits these payments across your monthly mortgage. If you pay directly, set calendar reminders to avoid late penalties.
Section 4

Supplemental Tax Bills

Supplemental taxes in Marin County are additional property tax bills issued when there is a change in ownership or completion of new construction that increases a property's assessed value during the tax year. These supplemental assessments are triggered by events such as property sales, transfers, or the completion of building permits for additions or new structures. The supplemental tax represents the difference between the old assessed value and the new assessed value, prorated for the remaining months in the fiscal year.

Supplemental tax bills are calculated by taking the difference between the previous assessed value and the new assessed value, multiplying by the property's tax rate, and prorating for the number of months remaining in the tax year (July 1 through June 30). For example, if a property sells in January and the assessed value increases from $800,000 to $1,200,000, the supplemental tax would be calculated on the $400,000 difference, multiplied by the tax rate, and prorated for the remaining five months of the fiscal year. Supplemental tax bills are mailed separately from regular property tax bills and have their own due dates, typically 30 days from the bill date, with delinquency occurring if not paid within that timeframe.

Example Calculation

Example 1: $300,000 Assessed Value (with Homeowners' Exemption)

  • Assessed Value: $300,000
  • Less Homeowners' Exemption: -$7,000 (must file application by February 15)
  • Net Taxable Value: $293,000
  • Tax Rate (estimated): 1.15%
  • Annual Tax: $3,370
  • Monthly (if escrowed): $281

Example 2: $600,000 Assessed Value (with Homeowners' Exemption)

  • Assessed Value: $600,000
  • Less Homeowners' Exemption: -$7,000 (application required)
  • Net Taxable Value: $593,000
  • Tax Rate (estimated): 1.20%
  • Annual Tax: $7,116
  • Monthly (if escrowed): $593

Example 3: $1,000,000 Assessed Value (with Homeowners' Exemption)

  • Assessed Value: $1,000,000
  • Less Homeowners' Exemption: -$7,000 (application required)
  • Net Taxable Value: $993,000
  • Tax Rate (estimated): 1.25%
  • Annual Tax: $12,413
  • Monthly (if escrowed): $1,034

Note: The Homeowners' Exemption is NOT automatic and requires filing Form BOE-266 by February 15. Tax rates vary by Tax Rate Area. Additional exemptions for seniors, veterans, or disabled persons may be available but require separate applications with specific deadlines.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Marin County require borrowers to maintain an escrow account for property taxes, particularly for loans with less than 20% down payment. The lender collects 1/12 of the estimated annual property tax bill with each monthly mortgage payment and holds these funds in a separate escrow account. When property tax bills are due on December 10 and April 10, the lender pays the taxes directly to the Marin County Treasurer-Tax Collector on behalf of the homeowner.

Lenders typically review escrow accounts annually and may adjust monthly payments based on actual tax bills and projected changes in assessed value. If your property taxes increase due to reassessment or new special assessments, your monthly escrow payment will likely increase. Homeowners should verify that their lender has paid property taxes on time by checking the Marin County Treasurer-Tax Collector website or calling (415) 473-7215. If you pay your own property taxes (without escrow), you are responsible for making payments by December 10 for the first installment and April 10 for the second installment to avoid penalties and potential tax lien procedures.

How HonestCasa Helps
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Section 6

Frequently Asked Questions

When are property taxes due in Marin County for FY 2024-2025? Property taxes are due in two installments: first installment by December 10, 2024, and second installment by April 10, 2025. Payments received after these dates are subject to penalties.

What tax credits are available and how do I apply? The primary credit is the Homeowners' Exemption, which reduces assessed value by $7,000 (saving approximately $70-80 annually). You must file Form BOE-266 by February 15. Additional credits may be available for seniors, veterans, or disabled persons, but each requires a separate application with specific deadlines and qualifications.

How does the Homeowners' Exemption work? The Homeowners' Exemption reduces your home's assessed value by $7,000, not the tax bill directly. This exemption is NOT automatic - you must file an application by February 15 with the Marin County Assessor. Once approved, it generally continues unless you move or change the property's use.

How often is my property reassessed? Under Proposition 13, your assessed value can only increase by a maximum of 2% per year unless there's a change in ownership or new construction. The county reassesses all properties annually as of January 1, but increases are capped at 2% or the inflation rate, whichever is lower.

How do I appeal my property tax assessment? If you believe your assessed value is too high, you can file an appeal with the Marin County Assessment Appeals Board. Applications must be filed between July 2 and September 15 (or November 30 in certain circumstances). Contact the Clerk of the Board at (415) 473-7294.

What happens if I pay my property taxes late? Late payments incur a 10% penalty immediately after the due date, plus additional penalties and interest. If taxes remain unpaid for five years, the property may be subject to the tax defaulted property auction process.

Can I pay my property taxes online? Yes, Marin County offers online payment options through their official website. You can pay by electronic check or credit card, though credit card payments may incur processing fees. Visit the Marin County Treasurer-Tax Collector website for secure online payment options.

What are special district taxes and Mello-Roos? Special district taxes fund specific services like fire protection, libraries, or parks within defined geographic areas. Mello-Roos taxes (Community Facilities Districts) are voter-approved assessments typically found in newer developments to fund infrastructure and services. These appear as separate line items on your tax bill and vary by location within the county.

Verified Sources

Backed by 10 Official Government Sources

Every fact in this guide is sourced from official county, state, and federal documents.

01
Tax Doc
BOE Tax Rate Area Mapsboe.ca.gov
02
PDFboe.ca.gov
03
State
[PDF] California Property Tax: An Overviewboe.ca.gov
04
Tax Doc
Property Tax Calendarmarincounty.gov
05
Tax Doc
News Release — Second Installment of Property Taxes Duemarincounty.gov
06
Tax Doc
Secured Property Tax Due Date & Late Penaltiesmarincounty.gov
07
Homeowners' Exemptionarcc.marincounty.gov
08
Tax Doc
BOE-266 - Claim for Homeowners' Property Tax Exemptionarcc.marincounty.gov
09
Tax Doc
Property Tax FAQsmarincounty.gov
10
Tax Doc
Property Tax Bill Detailsapps.marincounty.gov
All sources verified as of 2025 Tax Year

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