Missouri: Revocable Trust Amendment Requirements

Requirements one by one

Governing law and revocability presumption

Subsection 1 of Mo. Rev. Stat. § 456.6-602 permits amendment unless the trust terms
expressly provide that the trust is irrevocable. The statutory default does not
apply to a trust created under an instrument executed before January 1, 2005.

That cutoff makes the instrument's execution history material. The current
default does not itself establish amendment authority for every older Missouri
trust.

Who may amend or restate

The settlor is the ordinary actor. Subsections 5–6 of § 456.6-602 separately supply
limited routes for an expressly authorized agent and a court-approved
conservator or conservator ad litem. Trustee or beneficiary status alone does
not confer amendment authority.

Missouri states no distinct lifetime-restatement route. A complete restatement
is a comprehensive amendment and must satisfy the same authority and method
rules.

Trust method and exclusivity

If the trust supplies a method, the settlor may substantially comply with any
method it provides. The statutory intent fallback appears only when the trust
terms provide no method.

Missouri therefore does not preserve that fallback merely because a stated
method is nonexclusive. A method remains the statutory route whenever the trust
provides one.

Alternative intent or probated-will method

When the trust provides no method, the settlor may use any other method
manifesting clear and convincing evidence of intent. The statute expressly
includes the terms of a later duly probated will or codicil that identify the
trust being revoked or the trust terms being amended.

Probate and identification are part of Missouri's will route. A will or codicil
that has not been duly probated does not satisfy the express example in
subsection 3(2) of § 456.6-602.

Signature, witnesses, notary, and delivery

The trust's own method controls its required signing, witnessing, notarization,
or delivery acts. A settlor using the statutory will-or-codicil example must
have the duly probated and sufficiently identifying instrument described in
subsection 3(2).

The other no-method fallback turns on clear and convincing evidence of intent.
Section 456.6-602 itself states no universal amendment writing, signature,
witness, acknowledgment, notarization, trustee-delivery, or trustee-acceptance
requirement.

Capacity standard

Mo. Rev. Stat. § 456.6-601 makes the capacity required to amend a revocable
trust the same as the capacity required to make a will. The same comparison
covers creation, revocation, adding property, and directing the trustee.

Multiple settlors and contributed property

Community property may be amended only by both spouses acting jointly. For
property other than community property, each settlor may amend the portion
attributable to that settlor's contribution.

Subsection 2 of § 456.6-602 states no general prompt-notice duty to the other settlors
when fewer than all act within their allocated authority.

Agent, guardian, conservator, and court authority

An agent may exercise amendment powers only to the extent expressly authorized
by the trust terms or the power of attorney. Missouri uses an either-document
rule rather than requiring the express grant in both.

A conservator—or a conservator ad litem if no conservator has been appointed—
may act only with approval from the court supervising that fiduciary. Section
456.6-602 states no separate guardian amendment route.

Effective time, notice, and trustee protection

The applicable trust method or no-method evidentiary route determines when its
required acts are complete. Section 456.6-602 states no general beneficiary
notice, co-settlor notice, trustee receipt, trustee acknowledgment, or trustee
acceptance condition for an amendment.

Under subsection 7, a trustee without knowledge of the amendment is not liable
to the settlor or successors for distributions and other actions taken on the
assumption that the old terms remain operative.

What trips people up

• Using the fallback for a nonexclusive method. Missouri makes it available
  only when the trust provides no method at all.
• Treating any later will as immediately operative. The statutory example
  requires a duly probated will or codicil that identifies the trust or amended
  terms.
• Requiring express agent authority in two documents. The trust or the
  power of attorney may supply it.
• Substituting an ordinary guardian. The statute names a conservator or,
  if none, a conservator ad litem and requires supervising-court approval.

Common questions

Must a Missouri amendment be written, witnessed, or notarized?

Section 456.6-602 states no universal formality for every route. The trust
method controls when one exists; when none exists, any method may work if it
manifests clear and convincing evidence of intent.

Can one settlor amend the entire trust?

Not automatically. Community property requires joint spouses for amendment;
other property follows each settlor's contribution.

Does an agent need express authority in both the trust and power of attorney?

No. Subsection 5 of § 456.6-602 permits the trust or the power of attorney to supply the
express authority.

Statutes and sources

• Mo. Rev. Stat. § 456.6-601 — will-equivalent amendment capacity.
  Official Missouri Revisor
  text
  (accessed 2026-08-10).
• Mo. Rev. Stat. § 456.6-602 — revocability default, methods, multiple
  settlors, agent and conservator authority, and trustee protection. Official
  Missouri Revisor
  text
  (accessed 2026-08-10).