By Corcoran Smith Law Corp. · Updated
Modifying or Terminating a California Trust: Probate Code 15409, 15403 and 15404
Under California Probate Code section 15409, a court may modify or terminate a trust on a trustee's or beneficiary's petition when circumstances the settlor did not know of or anticipate mean that continuing under its terms would defeat or substantially impair the trust's purposes. Two consent routes need no such showing: the settlor and all beneficiaries in writing under section 15404, or all beneficiaries petitioning the court under section 15403.
Three routes, and which one is actually open to you
The word irrevocable misleads people into thinking nothing can be done. Three common routes follow. Under Probate Code section 15404, a trust may be modified or terminated by the written consent of the settlor and all beneficiaries without any court approval — the cleanest route, and the one that closes permanently when the settlor dies. Under section 15403, if all beneficiaries of an irrevocable trust consent they may petition the court, though the court will not act where continuing the trust is necessary to carry out a material purpose unless the reason for modifying outweighs that purpose. Under section 15409, the court may modify administrative or dispositive provisions, or terminate, on petition by a trustee or beneficiary where owing to circumstances not known to and not anticipated by the settlor, continuing under the trust’s terms would defeat or substantially impair its purposes. Section 15409 is the route that does not require everyone to agree, which in a contested family is usually the only one that is real.
Sources: Probate Code s.15403 - Modification or termination on consent of all beneficiaries · Probate Code s.15404 - Modification by settlor and all beneficiaries · Probate Code s.15409 - Modification on changed circumstances · Verified 2026-09-21.
Which route fits which situation
| Route | Who must agree | Court needed? | Available after the settlor dies? |
|---|---|---|---|
| §15404 | Settlor and all beneficiaries | No | No |
| §15403 | All beneficiaries | Yes | Yes |
| §15409 | No consent requirement | Yes | Yes |
Probate Code section 15409, explained
Section 15409 is the court's power to fix a trust that circumstances have overtaken. It has four working parts. First, standing: the petition may be brought by a trustee or by a beneficiary, and nobody else's consent is required. Second, the test: the circumstances must have been not known to the settlor and not anticipated by the settlor, and because of them, continuing the trust under its terms would defeat or substantially impair the accomplishment of the trust's purposes. Third, the remedy: the court may modify the administrative provisions, modify the dispositive provisions, or terminate the trust, and if necessary to carry out the trust's purposes it may order the trustee to do acts the instrument does not authorize or even forbids. Fourth, spendthrift language: under subdivision (b), a provision restraining transfer of a beneficiary's interest is a factor the court must consider, but it does not by itself prevent the court from modifying or terminating the trust.
Sources: Probate Code s.15409 - Modification on changed circumstances · Verified 2026-08-17.
What a 15409 petition has to show
- The trust's purposes. What the settlor was trying to achieve, drawn from the instrument and its context. The whole test is measured against these.
- The change. The specific circumstances that arose, with evidence of when.
- That the settlor neither knew nor anticipated it. A circumstance the settlor knew about and planned around does not qualify, however inconvenient it has become.
- The impairment. Why following the terms as written would now defeat or substantially impair those purposes, rather than merely produce a result some beneficiaries dislike.
- The narrowest fix. The modification, termination or trustee instruction requested, and why it is necessary to carry out the purposes.
Situations that fit, and situations that do not
| Fact pattern | Could 15409 apply? | Why |
|---|---|---|
| An administrative provision now costs more to follow than the asset is worth | Potentially | The cost problem must arise from circumstances the settlor neither knew nor anticipated, and continuing under the terms must defeat or substantially impair the trust's purposes |
| A co-trustee structure deadlocks in a way the settlor never contemplated | Potentially | The circumstances must be unknown to and unanticipated by the settlor, and the deadlock must defeat or substantially impair the trust's purposes |
| A distribution scheme was built around facts that no longer exist | Possibly | Turns on whether the settlor anticipated the change |
| Beneficiaries simply prefer a different division | No | Preference is not a circumstance that impairs the trust's purposes |
| The settlor was pressured into the terms | No | That is a validity problem: a trust contest, not modification |
Why this matters in a dispute
Modification is usually thought of as estate planning housekeeping, but it does real work in litigation. A trust whose terms have become unworkable — a co-trustee structure that deadlocks, a distribution scheme overtaken by events the settlor never saw, an administrative provision that costs more to follow than the asset is worth — can sometimes be fixed under section 15409 rather than fought over for years. It is also the answer when the fight is not really about the instrument’s validity at all, so a contest would be the wrong tool.
Sections 15403 and 15404: when everyone agrees
The consent routes are narrower than they look. Under section 15404, the settlor and all beneficiaries can modify or terminate a trust by written consent with no court involvement at all, and if one beneficiary will not consent, the court may still modify or partially terminate the trust on petition by the other beneficiaries with the settlor's consent, provided the non-consenting beneficiaries' interests are not substantially impaired. Under section 15403, if all beneficiaries of an irrevocable trust consent, they may petition the court, but if continuing the trust is necessary to carry out a material purpose, the court modifies or terminates only if the reason for doing so outweighs that purpose, and a trust under a valid spendthrift restraint may be terminated only for good cause. Both sections let the court limit a class described only as heirs or next of kin to the beneficiaries reasonably likely to take, so a remote contingent heir does not automatically block agreement.
Sources: Probate Code s.15403 - Modification or termination on consent of all beneficiaries · Probate Code s.15404 - Modification by settlor and all beneficiaries · Verified 2026-09-21.
Section 15408: trusts too small to run
A separate section deals with trusts whose value no longer justifies the cost of administering them. Under section 15408, on petition by a trustee or beneficiary, if the principal has become so low in relation to administration cost that continuing under the existing terms would defeat or substantially impair the trust's purposes, the court may terminate or modify the trust or appoint a new trustee, in a manner that conforms as nearly as possible to the settlor's intention. Where the principal does not exceed one hundred thousand dollars, the trustee has the power to terminate without a petition, under the amendment effective January 1, 2025. A spendthrift provision does not prevent either route.
Sources: Probate Code s.15408 - Uneconomic trusts · Verified 2026-09-17.
The limit the statute sets
Section 15409 lets the court order the trustee to do acts that are not authorised, or are forbidden, by the trust instrument — but only where necessary to carry out the trust’s purposes. The provision is corrective, not an invitation to rewrite a settlor’s plan into one the beneficiaries prefer. Where a restraint on transfer of a beneficiary’s interest exists, the court weighs it as a factor but is not barred from acting because of it.
Related: contesting the instrument instead, breaking a co-trustee deadlock, what beneficiaries are owed, and how litigation actually runs.
Common questions
Can an irrevocable trust be changed in California?
Yes. California provides several routes, depending on the trust and the circumstances. Under Probate Code section 15404, the settlor and all beneficiaries may consent in writing without court approval. Under section 15403, consenting beneficiaries may petition the court, subject to material-purpose and other limits. Section 15409 permits court relief where unanticipated circumstances would defeat or substantially impair the trust's purposes. These are common routes, not an exhaustive list.
What does California Probate Code section 15409 allow a court to do?
California Probate Code section 15409 lets a court, on petition by a trustee or beneficiary, modify a trust's administrative or dispositive provisions, or terminate the trust, where owing to circumstances not known to and not anticipated by the settlor, continuing under its terms would defeat or substantially impair its purposes. It does not require everyone to agree. The court may order acts the trust instrument does not authorize or forbids, but only where necessary to carry out the trust's purposes.
Can a California trust be modified after the settlor dies?
Some routes remain open. Under California Probate Code section 15404, the settlor and all beneficiaries can modify or terminate a trust by written consent without court approval, but that route closes permanently when the settlor dies. After death, all beneficiaries may still petition the court under section 15403, and a trustee or beneficiary may petition under section 15409 where unanticipated circumstances would defeat or substantially impair the trust's purposes. Both of those routes require a court.
Can all the beneficiaries agree to modify or end an irrevocable trust?
Under California Probate Code section 15403, if all beneficiaries of an irrevocable trust consent, they may petition the court to modify or terminate it. The court will not act where continuing the trust is necessary to carry out a material purpose, unless the reason for modifying outweighs that purpose. Where the trust holds a valid restraint on transfer of a beneficiary's interest, termination additionally requires the court to find good cause.
Need help with legal fees?
We litigate select cases on contingency, with no upfront fees.
Costs are separate from the fee, and whether you are responsible for them is set out in the written agreement before you sign anything.
How contingency fees work in California
A contingency fee means the attorney is paid from what is recovered rather than by the hour, so a beneficiary who cannot fund litigation out of pocket can still bring a claim. California regulates these agreements closely. Under Business and Professions Code section 6147, the agreement must be in writing and the attorney must give the client a duplicate copy, signed by both, when the contract is made. It must state the agreed contingency rate; how disbursements and costs incurred in prosecuting or settling the claim will affect that fee; and to what extent the client could be required to pay for related matters. Unless the matter falls under section 6146, the agreement must also state that the fee is not set by law and is negotiable. These are not formalities: failure to comply with any provision of section 6147 makes the agreement voidable at the client’s option, leaving the attorney entitled only to a reasonable fee.
Sources: Business and Professions Code s.6147 - Contingency fee contracts · Verified 2026-08-03.
Not every matter suits a contingency arrangement, and the firm does not take every case on one. Whether yours qualifies depends on the facts, the likely recovery, and the assets actually available to satisfy a judgment. Ask when you call.
Call Anytime — Answered 24/7 · (213) 695-7353The Probate Code sections behind this page
Each section links to its official text at the California Legislature’s own site. The full index of sections covers the rest of the Code.
- Probate Code section 15403
- Modification or termination on consent of all beneficiaries. Read section 15403
- Probate Code section 15404
- Modification by settlor and all beneficiaries. Read section 15404
- Probate Code section 15409
- Modification on changed circumstances. Read section 15409
Before you call: What a dispute costs · How a case runs · Which court hears it
Attorney, fiduciary or financial advisor with a client matter? How to refer a California probate or trust matter