The short answer
Until the close of business on the last business day before the auction begins; no redemption after the sale
How the clock works
Tax-defaulted property may be redeemed until the right of redemption is terminated (section 4101). That right terminates at the close of business on the last business day prior to the commencement date of the tax sale, and the start of the auction counts as the sale date no matter when bidding closes. A redemption payment sent by mail must be received in the tax collector's office before that deadline. California has no post-sale redemption period: once the auction opens, a record owner who has not redeemed loses all legal and equitable interest in the property. Two situations revive the right of redemption. The right revives if the property is not sold, and it revives on the next business day if the tax collector approved a credit sale and the buyer did not pay in full by the deadline the tax collector set.
Who can redeem
Part 7 does not restrict redemption to a named class of persons. Any person may pay, application to redeem is made to the tax collector as the county redemption officer, and the tax collector prepares an estimate of the amount necessary to redeem. Separately, any person may elect to pay delinquent taxes on a permanent installment plan at any time before 5 p.m. on the last business day prior to the date the tax collector obtains the power to sell the property, which keeps the parcel out of the auction while the plan stays current.
What the owner pays to redeem
The total of all prior year defaulted taxes, delinquent penalties and costs, redemption penalties, and a redemption fee of $15 on each separately valued parcel tax defaulted on or after January 1, 1984. Redemption penalties run at 1.5 percent a month, which is 18 percent a year, on the declared defaulted amount from July 1 of the year of the declaration of default, plus 1.5 percent a month on each later year's unpaid taxes from July 1 of that year. Extra fees apply once the county has started sale preparation, including a $150 fee under section 4112 if redemption is within 90 days of the proposed sale date.
How your interest accrues
Not applicable to investors. Redemption penalties of 1.5 percent a month accrue to the county, not to a private certificate holder. They run from July 1 of the year of the declaration of default on the defaulted amount, and from July 1 of each later year on that year's unpaid taxes, until the property is redeemed. The buyer at a tax deed auction earns no interest; the return comes from the property itself.
Why some certificates are bid to zero
Not applicable. California runs no interest bid-down auction, so there is no zero-percent bid and no minimum-return floor.
What happens when it ends
Five years or more after the property is declared tax defaulted, the tax collector has the power to sell and must attempt to sell the parcel. The period is three years or more for nonresidential commercial property, which excludes residential units used or zoned as permanent residences and land used and zoned for commercial agricultural production, unless the county has adopted an ordinance applying the five-year period to that property too. A city, county, city and county, or qualifying nonprofit can also ask the tax collector to bring non-owner-occupied residential property delinquent at least three years to the next scheduled auction, and so can a holder of a recorded nuisance abatement lien.
A redeemed certificate, plus your accrued interest, is what makes the wait profitable; see how redemption periods work across states. An unredeemed certificate is instead your path to the property through a tax deed sale, which still does not convey marketable title on its own, so budget for a quiet title action.
Verified Jul 25, 2026 against California statutes.
Tax Sale Atlas publishes educational information about public tax sale processes. This is not legal, financial, or investment advice. Rules, dates, and fees change; confirm with the county office before you bid.