A drafting defect is fixed by a modification or reformation petition brought through Prob. Code § 17200. If every beneficiary agrees, Prob. Code § 15403 lets them consent and petition together, subject to the court's authority to refuse where continuing the trust as written is necessary to a material purpose. If someone will not consent, or the mistake produces a result the settlor plainly never anticipated, Prob. Code § 15409 permits the court to modify the trust where unanticipated circumstances would defeat or substantially impair its purposes. Separately, California courts can reform an instrument to conform it to what the settlor actually intended where clear and convincing evidence shows the terms were affected by a mistake — that is a judge-made doctrine, not a code section, and it lives or dies on evidence. Prior drafts, the drafting attorney's file, signed instruction letters and contemporaneous notes are what win these cases, so gather them before memories fade.
Fixing or Changing a Trust · California
Can a mistake in a trust be fixed after the person who made it has died?
Often, yes. Death makes a revocable trust irrevocable, so nobody can simply sign a correction, but a mistake is not the same thing as a change of mind, and California courts are willing to correct genuine mistakes. The first question is what kind of defect you actually have, because two very different problems get described with the same word. One is a funding defect: the house or the brokerage account was supposed to be in the trust, everyone understood it was in the trust, but the deed or the account title never caught up. The other is a drafting defect: the assets are titled correctly, but the words inside the trust do not say what your parent meant them to say — a share that adds up to more than one hundred percent, a subtrust that names no beneficiary, a clause that contradicts the one before it. Same client, different defect, and the two problems are fixed by different petitions. Sorting out which one you have is the first hour of the work, not an afterthought.
This page is general information about California law, not legal advice, and does not create an attorney-client relationship. Figures and deadlines change, and every family’s situation is different. Last reviewed August 2026.
Related Questions
The questions this one leads to.
How is a trust modification petition different from a Heggstad petition?
A Heggstad petition confirms an asset was already in the trust. A modification petition changes what the trust says. How to tell which one you need.
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Usually not. When a misspelled name in a California trust actually matters, and how a court resolves the ambiguity when the trustee cannot tell who takes.
Read the answerCan an irrevocable trust be changed in California?
Yes, in defined circumstances. The three California routes to change an irrevocable trust, who has to sign each one, and when a judge has to approve it.
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