Property tax due dates in California are set by state law, so the calendar for a mid-century house in Sunnyvale, San Mateo or Oakland is normally the same: two installments, two delinquency dates and a hard stop on June 30. What differs by county is the fine print, such as the dollar cost added to a late second installment and how you ask for a penalty to be waived.
This guide covers the regular secured tax bill using the Revenue and Taxation Code, the Board of Equalization's (BOE) property tax overview, and pages from the Santa Clara County Department of Tax and Collections, the San Mateo County Tax Collector and the Alameda County Treasurer-Tax Collector, all read on November 6, 2026. Dates, costs and fees can change, so confirm them with your county before you pay.
The secured bill and its two installments
The BOE's overview says bills for the regular secured roll, generally real property, are mailed by November 1 and are due in two equal installments. Revenue and Taxation Code section 2610.5 has the tax collector mail or electronically send a bill for every secured property on or before November 1.
The calendar, as of November 2026:
November 1. The first installment is due (section 2605).
December 10. The first installment becomes delinquent at 5 p.m., or the close of business if later (section 2617).
February 1. The second installment is due (section 2606).
April 10. The second installment becomes delinquent at 5 p.m., or the close of business if later (section 2618).
June 30. The last day before unpaid taxes go into default.
Santa Clara County's property tax calendar lists the same dates, says secured bills are mailed in October, and calls June 30 the last day to pay the current year's taxes without additional penalties.
Section 2700 lets a county's board of supervisors adopt an alternative installment system instead, so the date printed on your own bill is the one to follow. Supplemental bills after a purchase or new construction run on their own schedule, covered in our guide to supplemental property tax in California.
Delinquency, the 10 percent penalty and the cost
Sections 2617 and 2618 add a 10 percent penalty to each installment that isn't paid by its delinquency date. After the second installment becomes delinquent, section 2621, as amended effective January 1, 2023, lets the tax collector add a cost of up to $55, but no more than the actual cost, on each separate valuation.
The county pages we read handle that cost differently, as of November 2026:
San Mateo County. The tax collector's secured property tax page says a second installment unpaid as of April 10 gets a 10% penalty and a $40.00 cost.
Alameda County. After 5 p.m. on April 10, a 10% penalty and a $10 cost attach.
Santa Clara County. Its secured tax page gives no cost amount and refers you to the tax bill's notes on penalties and fees.
San Mateo and Alameda counties say that when a delinquency date falls on a weekend or holiday, no penalty is charged if you pay by 5 p.m. on the next business day. Santa Clara County says that when December 10 or April 10 falls on a weekend or a county holiday, the delinquent date moves to the next business day. San Mateo County adds a rule for mailed payments: the envelope needs a United States Postal Service postmark on or before the delinquency date, and the tax collector must accept the postmark, not a private meter date.
If the taxes are still unpaid on June 30
Under section 3436, unpaid taxes, assessments, penalties and costs on real property are declared in default by operation of law at 12:01 a.m. on July 1.
Redemption penalties. Section 4103 adds 1½ percent a month on the defaulted taxes, starting July 1 of the year of default, until they are paid.
A redemption fee. San Mateo County lists a $35 redemption fee on delinquent parcels. Alameda County's FAQ lists a redemption fee without giving the amount.
Five years. The BOE says an owner can redeem by paying the taxes, penalties and costs within five years of the date the property becomes tax-defaulted. If it isn't redeemed, the property may be sold at public auction or acquired by a public agency. Alameda County's FAQ says that after five years the tax collector has the power to sell tax-defaulted property that is not redeemed.
The BOE also warns that an unpaid supplemental bill can put the whole property into default, even when the regular taxes have been paid.
Paying through an impound account
Some owners' taxes are paid by their lender from an impound account. Section 2610.5 says that not receiving a bill doesn't relieve the tax lien or prevent penalties. The state's Preliminary Change of Ownership Report (BOE-502-A), which buyers file at closing, warns that supplemental assessments are not included in lender impound accounts and that "you may be responsible for the current or upcoming property taxes even if you do not receive the tax bill."
A few habits help:
After each delinquency date, check with your county that the installment posted, rather than assuming the servicer paid it.
Plan to pay supplemental bills yourself, as our supplemental tax guide explains.
If your lender stops paying the taxes, Alameda County's FAQ notes that you don't need a payment stub to pay, and that you can order a duplicate bill or use the informational copy stubs you receive each year by November 1.
Keep your mailing address current with your county. San Mateo County says a bill sent to an old address because you didn't update it doesn't qualify for a penalty waiver.
Asking for a penalty to be canceled
Penalties can be canceled only in limited cases. As of November 2026, the grounds in the code sections we read include:
Reasonable cause. Section 4985.2 allows cancellation when the late payment was due to reasonable cause and circumstances beyond the taxpayer's control, the taxpayer used ordinary care and there was no willful neglect, and the tax itself is paid by June 30 of the fourth fiscal year after it became delinquent.
An inadvertent amount error. Section 4985.2 also covers an inadvertent error in the amount paid, if the right amount is paid within 10 days after the notice of the shortage.
A bill that wasn't mailed. Section 2610.5 cancels penalties when the delinquency was caused by the tax collector's failure to mail the bill to the address on the roll.
A late or corrected bill. Under section 2610.5, penalties on a bill mailed late or corrected are canceled if it is paid within 30 days after mailing, and no taxpayer has fewer than 30 days to pay without penalty.
San Mateo County's penalty appeal page shows how one county runs this. You file its Application for Waiver of Delinquent Penalties/Fees with documentation and two checks, one for the tax and one for the penalty and fee only. The county says it won't consider an application received without payment. If the appeal is approved, the penalty check is returned. Failure to receive a bill that was mailed on time is not a qualifying reason. Appeals go to the tax collector's appeals unit, not the payment post office box.
Santa Clara County's penalty cancellation page also asks you to pay in full first, penalty included, and then submit a signed request with documentation. If the penalty is canceled, the county refunds it, and the page says a decision may take up to 6 months. It also lists requests it will deny, among them a postage-meter date, home banking or online bill payments, and not receiving a tax bill. Alameda County has its own process, so ask yours.
This is general information as of November 2026, not legal or tax advice. Check dates and amounts with your county tax collector, and talk with a tax advisor about your situation.
A payment checklist for Bay Area owners
Put December 10 and April 10 on your calendar, and pay before 5 p.m.
Mail early, and use the Postal Service if you're mailing close to the deadline.
If you pay by card, expect a fee. San Mateo County lists a 2.35% service fee, Santa Clara County lists 2.22% with a $1.49 minimum and no fee for eCheck, and Alameda County charges a convenience fee and takes cards only by phone or online.
If you live in the home, check that your bill shows the homeowners' exemption. Our guide to the homeowners' exemption in California explains how to claim it.
Watch for supplemental bills in your first year of ownership.
If you think your assessed value is too high, keep paying on time while you ask for a review. Our guide to a Prop 8 decline-in-value review explains the steps.
Frequently asked questions
When are property taxes due in California?
The first installment is due November 1 and becomes delinquent after December 10. The second is due February 1 and becomes delinquent after April 10. Both deadlines are 5 p.m. or the close of business, whichever is later, and the counties we checked move them to the next business day when the date falls on a weekend or holiday.
What is the penalty for paying property taxes late?
Each late installment gets a 10 percent penalty. A late second installment also gets a cost, capped at $55 by section 2621: $40 in San Mateo County and $10 in Alameda County, as of November 2026.
What happens if I miss the June 30 deadline?
The taxes go into default on July 1 and redemption penalties of 1.5 percent a month start; San Mateo County also adds a $35 redemption fee. The BOE says that if the property isn't redeemed within five years, it may be sold at public auction or acquired by a public agency.
My lender pays through an impound account. Do I need to do anything?
Yes. Check that each installment posts, and pay supplemental bills yourself, since the state's PCOR form says they aren't included in impound accounts. Not receiving a bill doesn't excuse a penalty.
Related reading
Prop 19 Base Year Transfer: 55+, Disabled and Disaster Moves
Prop 19 Inherited Home Rules: A Guide for Heirs of Mid-Century Houses
Bay Area Transfer Tax by City: County and City Rates for Sellers
More guides on this topic: Buying & Selling a Mid-Century Modern Home
Buying or owning a mid-century home in the Bay Area? Call or text the Boyenga Team at Compass at (408) 373-1660 or (650) 383-8606, or contact the Boyenga Team with questions about the house and the costs of owning it.
