Thinking about a move to Contra Costa but worried your property taxes will spike? If you are 55 or older, severely and permanently disabled, or a qualified disaster victim, California’s Prop 19 can help you bring your lower tax base with you. That can mean real monthly savings when you buy your next primary home. In this guide, you will learn who qualifies, how the calculation works, the forms to file in Contra Costa County, and simple steps to make your move smoother. Let’s dive in.
What Prop 19 does for Contra Costa moves
Prop 19 lets eligible homeowners transfer their existing “Prop 13” taxable value to a replacement primary residence anywhere in California, including any city or town in Contra Costa County. You can generally use this benefit up to three times if you are 55 or older or severely disabled. Qualified disaster victims are not limited in number of transfers. The replacement home must be bought or newly built within two years before or after the sale of your original home. You can review the statewide rules on the California Board of Equalization’s Prop 19 page.
You can transfer your base value even if the new home costs more. If the replacement home is higher in market value, your transferred value gets an upward adjustment equal to the price difference. If the new home is equal or less in value, you can carry your existing assessed value without an increase. Accessory dwelling units are treated as part of the primary residence for these rules. Guidance and examples are available on the BOE Prop 19 resource.
Who qualifies and when
Age 55 or older
If you are at least 55 at the time you sell your original home, you can transfer your base year value to your next primary residence. You can do this up to three times in your lifetime. Learn the core criteria on the BOE Prop 19 page.
Severe and permanent disability
If you are severely and permanently disabled, you can also transfer your base value to a replacement primary residence. Documentation from a physician is typically required. See filing tips under Forms and documents below and the BOE Prop 19 guidance.
Disaster victims
If your primary residence was substantially damaged or destroyed in a Governor‑declared disaster, you may transfer your base value to a replacement home. There is no numeric limit for disaster‑related transfers. For disaster relief background, see the BOE disaster relief overview.
How the tax transfer works
Equal or lower price example
Say you sell your home for 800,000 dollars and your current assessed value is 300,000 dollars. You buy your Contra Costa replacement home for 780,000 dollars. Under Prop 19, the 300,000 dollar assessed value transfers to the new home. That is the taxable value used to compute your property tax. See examples on the BOE Prop 19 page.
Higher price example
You sell for 800,000 dollars and carry a 300,000 dollar assessed value. You buy for 1,100,000 dollars. Your new taxable value becomes 300,000 plus the difference between 1,100,000 and 800,000, which equals 600,000 dollars. This simplified illustration mirrors the BOE method. For timing details, including the 100, 105, and 110 percent value tests tied to purchase timing, consult the BOE Prop 19 guidance.
Filing in Contra Costa
Where to file and deadlines
File your base year transfer claim with the Contra Costa County Assessor because your replacement home is in this county. Many counties allow up to three years from the replacement purchase or construction completion date to receive retroactive relief back to the purchase date. Earlier filing is better. Use the county’s Prop 19 page to start your claim: Contra Costa County Prop 19.
Forms and documents
Common forms include the Claim for Transfer of Base Year Value to Replacement Primary Residence (BOE 19‑B), the disability claim (BOE 19‑D), and the disaster claim (BOE 19‑V). Typical documents include proof of age or disability, grant deeds, closing statements, and disaster documentation if applicable. Access county forms and instructions on the Contra Costa Assessor forms page, and see checklists on the BOE Prop 19 page.
Escrow coordination
Tell your lender and escrow officer early that you plan to claim a Prop 19 transfer. The Assessor’s review can take weeks or months, which can affect tax prorations and impounds. Proactive coordination helps you avoid surprises. County processing info and contact details are available on the Assessor forms and instructions page.
Planning your move step by step
- Confirm eligibility. You must be 55 or older, severely disabled, or a qualified disaster victim. Review the basics on the BOE Prop 19 resource.
- Estimate your tax outcome. Share your current assessed value and estimated sale and purchase prices with the Assessor’s office to model the transferred value. Start with the Contra Costa Assessor forms and contacts.
- Loop in your lender and escrow. Let them know you intend to file a Prop 19 claim so they can plan tax prorations and impounds.
- Gather paperwork. Collect proof of age or disability, deeds, closing statements, and any disaster records. See requirements on the BOE Prop 19 page.
- File promptly. Submit the appropriate BOE 19 claim to the Contra Costa Assessor. Filing within three years helps you receive retroactive relief. Use the Contra Costa Prop 19 page to access current instructions.
- Review your estate plan if needed. If you own or may inherit property, Prop 19 changed intergenerational rules. Learn the basics and timelines using this county assessor guidance overview.
Inherited property rules you should know
Prop 19 narrowed the parent to child and grandparent to grandchild exclusions. An inherited family home can keep its lower taxable value only if the heir makes it their primary residence and files on time. There is also a value limit. If market value at transfer exceeds the prior taxable value by more than the current ceiling, the excess is added to the assessed value. See a clear summary of these changes in this assessor guidance. If you are planning a transfer or trust change, consult an estate professional.
Why this matters in Contra Costa
Local homeowners are using Prop 19 in significant numbers. Contra Costa reportedly had the most approved transfers in the Bay Area in fiscal year 2021 to 2022, with about 700 approved transfers, which influenced downsizing and relocation patterns countywide. You can read a regional snapshot in this San Francisco Chronicle analysis.
Common timelines to remember
You have a two‑year window centered on your sale to buy or complete new construction of your replacement home. Many counties, including Contra Costa, allow three years from purchase or completion to file for retroactive relief. For inherited property, counties often require occupancy and a homeowner’s exemption within one year for full relief. For timing basics and filing details, see the BOE Prop 19 page and this assessor guidance.
Quick answers to edge cases
Moving from another county into Contra Costa
Statewide portability means you can bring your base value from anywhere in California into Contra Costa if you qualify. File with the Contra Costa Assessor. Learn more on the BOE Prop 19 page.
What about homes with an ADU
For Prop 19, an accessory dwelling unit is treated as part of the primary residence. You only need to occupy one of the units as your primary home. See the ADU note in this assessor guidance.
Thinking about a Contra Costa move and want a clear plan for timing, pricing, and paperwork? Let’s map it out together so you can maximize your tax savings and buy with confidence. Reach out to Michelle Kennedy to start a no‑pressure conversation about your goals.
FAQs
What is Prop 19 and how can it lower my Contra Costa property taxes
- Prop 19 lets eligible homeowners transfer their lower assessed value to a replacement primary residence anywhere in California, including Contra Costa, subject to timing and value rules outlined by the BOE.
Who qualifies to transfer a tax base under Prop 19
- Homeowners who are 55 or older, severely and permanently disabled persons, and qualified disaster victims can transfer a base value under the statewide rules on the BOE Prop 19 page.
How do I calculate my new assessed value if my Contra Costa replacement home costs more
- Add your current assessed value to the difference between the replacement home’s market value and your original home’s market value, as illustrated by the BOE’s examples.
Where do I file my Prop 19 claim for a home in Contra Costa County
- File with the Contra Costa County Assessor using the county’s claim forms and instructions on the Prop 19 page and Assessor forms page.
What documents will I need for a Contra Costa Prop 19 claim
- Expect to provide deeds, closing statements, proof of age or a physician’s disability certificate, and disaster records if applicable, as outlined in the BOE Prop 19 guidance.
How did Prop 19 change inherited property assessments for families in California
- An inherited family home keeps its lower assessed value only if the heir makes it their primary residence and meets value and filing limits described in this assessor guidance.
