Missouri: Living Will and Advance Health-Care Instruction Requirements

Missouri uses a narrow written declaration under Chapter 459. It addresses an
adult's own request to withhold or withdraw defined death-prolonging procedures;
it is not the health-care-agent appointment governed elsewhere in Missouri law.

Requirements one by one

The declaration must be written, signed, and dated

Section 459.015.1 permits a competent adult to sign personally or direct
another person to sign in the adult's presence. The declaration must be dated.
Missouri provides an optional statutory form and permits additional specific
directions, but does not require the sample wording.

Witnesses depend on handwriting. A declaration not wholly in the adult's own
handwriting must be signed in the presence of two witnesses age 18 or older.
Neither witness may be the person who signed at the adult's direction. The
paragraph does not require witnesses for a wholly handwritten declaration and
does not offer notarization as an alternative.

Terminal condition and inability to decide are both required

Under § 459.025, the declaration becomes operative only when the condition
is terminal and the adult cannot make treatment decisions. Both determinations
must be placed in the medical record. A capable adult's current direction always
supersedes the earlier document.

The terminal-condition definition uses the attending physician's opinion: the
condition is incurable or irreversible and death will occur within a short time
regardless of medical procedures. Chapter 459 does not add permanent
unconsciousness or an end-stage-condition alternative.

Nutrition, hydration, pain relief, and comfort are outside the defined withdrawal

The declaration may direct withholding or withdrawal of a "death-prolonging
procedure." Section 459.010(3) expressly excludes medication or procedures
needed for comfort or pain relief and also excludes every procedure that
provides nutrition or hydration from that defined term.

Section 459.015.3 allows other specific directions in the document. That
permission does not rewrite the chapter's defined death-prolonging-procedure
mechanism or its express exclusions.

Pregnancy suspends the declaration's withdrawal instruction

Section 459.025 says a declaration to withdraw or withhold treatment has no
effect during the pregnancy after the attending physician diagnoses the adult
as pregnant. The sentence states no gestational-age, viability, live-birth, or
prognosis exception.

Chapter 459 separately says it does not authorize mercy killing, euthanasia, or
an affirmative or deliberate act or omission to shorten or end life.

Revocation is deliberately broad

Under § 459.020, the adult may revoke at any time and in any manner that
communicates an intent to revoke, regardless of mental or physical condition.
The provider places the revocation in the medical record. A person is not liable
for failing to act on it unless it is charted or that person actually knows of it.

Section 459.250 authorizes optional electronic submission of directives and
revocations to an Advance Health Care Directives Registry. Registration is not
an execution requirement, and failure to update the registry does not invalidate
an otherwise valid revocation.

A refusal triggers reasonable transfer steps

A provider with actual knowledge should not act contrary to the declaration
without a serious reason consistent with the adult's best interest, recorded in
the medical record. An unwilling attending physician must take reasonable steps
to transfer the adult to another physician; a facility whose policy prevents
compliance must take reasonable steps toward facility transfer.

Good-faith compliance under usual and customary medical standards receives the
immunity stated in § 459.040. Chapter 459 contains no separate rule giving an
out-of-state treatment instruction automatic recognition.

What trips people up

• Two witnesses are conditional. They are required when the declaration is
  not wholly in the adult's handwriting, not for every Missouri declaration.
• Nutrition and hydration are not included in the defined procedure. The
  statute expressly excludes them, along with pain relief and comfort care.
• Pregnancy is categorical in this chapter. The declaration has no effect
  during the pregnancy; the statute does not provide a customizable exception.
• Registry filing does not create validity. It is optional storage and
  access, not a substitute for the writing, signature, date, and witness rules.

Common questions

May I use a notary instead of witnesses?

No notary alternative appears in § 459.015. If the declaration is not wholly in
your handwriting, the statute calls for two adult witnesses.

May the declaration be oral?

No. Missouri's Chapter 459 declaration must be in writing, signed, and dated.
The broad communication rule applies to revocation, not initial execution.

Does the declaration control while I can still decide?

No. Your current direction supersedes the document. The declaration operates
only after the terminal-condition and inability-to-decide findings are recorded.

Statutes and sources

• Mo. Rev. Stat. §§ 459.010 and 459.015 — competence, terminal condition,
  death-prolonging-procedure exclusions, writing, signature, date, conditional
  witnesses, optional form, and physician notice. § 459.010 and
  § 459.015
  (accessed 2026-07-30).
• Mo. Rev. Stat. §§ 459.020 and 459.025 — broad revocation, record notation,
  terminal-and-incapacity trigger, current wishes, serious-reason notation, and
  pregnancy. § 459.020 and
  § 459.025
  (accessed 2026-07-30).
• Mo. Rev. Stat. §§ 459.030, 459.040, and 459.055 — transfer, immunity, and
  the euthanasia boundary. § 459.030,
  § 459.040, and
  § 459.055
  (accessed 2026-07-30).
• Mo. Rev. Stat. §§ 459.016 and 459.250 — DHSS form direction and optional
  registry. § 459.016 and
  § 459.250
  (accessed 2026-07-30).