The three California routes are worth naming precisely, because people mix them up constantly. Prob. Code § 15404 lets the settlor together with all beneficiaries modify or terminate by written consent with no court approval at all. It is the fastest and cheapest route, and it disappears the moment the settlor dies or loses capacity. Prob. Code § 15403 does not depend on the settlor being alive or dead. If all beneficiaries of an irrevocable trust consent, they may petition the court to modify or terminate, and the court may still refuse if continuing the trust unmodified is necessary to carry out a material purpose, unless the reason for the change outweighs that purpose. That covers the common case of a living settlor who will not or cannot consent. Prob. Code § 15409 is the equitable deviation route, allowing the court to modify administrative or dispositive provisions, or terminate the trust, where circumstances not known to and not anticipated by the settlor would defeat or substantially impair the trust's purposes. All of these reach the court through Prob. Code § 17200, the statute for petitions concerning the internal affairs of a trust.
Fixing or Changing a Trust · California
Can an irrevocable trust be changed in California?
Yes, in defined circumstances. "Irrevocable" means the person who created the trust gave up the power to change it whenever he or she felt like it. It does not mean the document is welded shut forever. California gives you three doors, and which one is open to you depends on who is willing to sign and whether you need a judge. If the settlor is alive, has capacity, and signs along with every single beneficiary, the change happens entirely on paper. If the settlor will not sign, cannot sign, or has died, the beneficiaries can still go to court and ask for the change. And if the problem is something nobody saw coming, a court can adjust the trust even over an objection: a beneficiary who developed a disability and would lose public benefits if she inherited outright, an administrative provision that has become impossible or absurdly expensive to follow, a tax rule that reversed after the trust was signed. What you cannot do is sign an amendment to an irrevocable trust the way you would amend a revocable living trust. That paper has no legal effect, and a trustee who distributes in reliance on it is personally exposed.
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.
Can all the beneficiaries just agree to change the trust?
Sometimes, and it turns on the word "all." Who counts as a beneficiary for a consent modification in California, and how minors and unborn heirs are represented.
Read the answerDoes the trustee need court approval to change a trust?
Usually the trustee cannot change the trust at all. What a California trustee risks personally by bending the terms, and how a court order protects them.
Read the answerMy mother put her house in an irrevocable trust before she got sick — can we undo it?
Possibly. Whether a California irrevocable trust holding a parent's house can be undone depends on her capacity, the beneficiaries, and why it was created.
Read the answerNext Step
Ask Robert P. Bergman about your own facts.
The 15-minute Consultation is free. Bring the assessor’s notice, the trust, or just the question, and you will leave knowing which deadline applies to you.
Robert P. Bergman is one of less than 1% of California attorneys certified as a specialist by the State Bar.