How to Make a Valid Will in Missouri

Missouri in depth

Missouri asks for a familiar core — a written will, signed and witnessed by two people — and then enforces it strictly. It flatly refuses handwritten (holographic) wills, gives judges no power to forgive a signing that went wrong, and keeps only one narrow escape hatch: a deathbed oral will that can pass no more than $500 of personal property. As of August 2025 it also recognizes electronic wills, a change so new that few Missouri wills have been made under it yet.

The statute facts above give you the rules. This section covers where Missouri wills actually go wrong, and the protections built into Missouri law that you cannot draft around.

Five ways a Missouri will gets thrown out

Most Missouri wills that fail, fail on how they were signed — not on what they say. And because Missouri has no harmless-error rule, a defect is usually fatal. These are the recurring ones.

1. 1

   Assuming a handwritten note counts as a will

   Missouri does not recognize holographic (handwritten, unwitnessed) wills at all. Section 474.320 requires every will to be in writing, signed by you, and attested by two or more competent witnesses who subscribe in your presence — with no exception for a document written entirely in your own hand. A heartfelt letter in a drawer, however clear and however clearly signed, is not a valid Missouri will without those two witnesses.

2. 2

   Using a beneficiary as one of your witnesses

   An interested witness does not void a Missouri will — but it can quietly shrink that witness's inheritance. Under § 474.330, a witness who also inherits forfeits any gift that exceeds what they would have received in intestacy, unless the will was also attested by two disinterested witnesses. Being a creditor of the estate or the named executor does not make a witness "interested." The clean fix is to use two witnesses who inherit nothing.

3. 3

   Relying on a notary instead of two witnesses

   Notarization does not make a Missouri will valid — two witnesses do (§ 474.320). A notary matters only for the optional self-proving affidavit (§ 474.337), which speeds probate but adds nothing to whether the will is legally valid. A carefully notarized will signed by fewer than two competent witnesses is not validly executed.

4. 4

   Counting on a deathbed oral will to carry the estate

   Missouri does recognize nuncupative (oral) wills, but the exception is tiny and easy to misjudge. It works only for a person in imminent peril of death who actually dies from it, who declares the will before two disinterested witnesses, whose words are reduced to writing within 30 days and probated within six months — and even then it can pass personal property only, up to an aggregate value of $500 (§ 474.340). It cannot transfer real estate and cannot move a real estate's worth of assets. Treat it as a last resort, never a plan.

5. 5

   Assuming a botched signing can be fixed later

   Some states let a court admit a defective will if it's convinced you intended it — a "harmless error" or dispensing rule. Missouri has not adopted one. Strict compliance with § 474.320 is required, so a will signed with only one witness cannot be rescued by proving your intent after you're gone. Get two competent, disinterested witnesses in the room, or the document is not a will.

You can't fully disinherit a spouse in Missouri

Missouri is not a community-property state, but it protects a surviving spouse through an elective share. A spouse who elects to take against the will can claim one-half of the estate if you left no lineal descendants, or one-third if you did (§ 474.160), plus exempt property and the statutory allowance on top of that share.

You cannot write around this by simply leaving your spouse out. If part of your plan depends on giving a spouse less than the elective share, build that share into the plan — through a valid waiver or other planning — rather than ignoring it, because the court will apply the elective-share math regardless of what the will says.

What happens if you die without a valid Missouri will

If your will is thrown out — or you never made one — Missouri's intestacy statute decides who inherits, and a surviving spouse's share depends entirely on the children (§ 474.010). With no descendants, the spouse takes the entire estate. Where all of your descendants are also the surviving spouse's, the spouse takes the first $20,000 plus one-half of the balance, and the descendants split the rest. But if you leave a descendant who is not your spouse's child, the spouse takes one-half with no $20,000 set-aside, and the descendants take the other half.

After the spouse and descendants, the estate passes to parents and siblings, then to more distant relatives. The point of a valid will is to override this default entirely — a blended family in particular can end up with a division no one intended once the $20,000 set-aside drops away.

The self-proving affidavit, and where a Missouri will is proved

Missouri does not require notarization for a will to be valid, but it does offer a self-proving affidavit: at signing or any later date, you and your two witnesses can swear before a notary, using the statutory form, that the will was properly executed (§ 474.337). A self-proved will can usually be admitted without tracking down the witnesses to testify years later. Execute the affidavit the same day you sign; it is far harder to arrange after the fact.

Missouri probates wills in the Probate Division of the Circuit Court, in the county where you were domiciled — your primary residence — at death (§ 473.010). Small estates can skip formal probate: where the estate, less debts and liens, does not exceed $40,000, an heir can use a small-estate affidavit beginning 30 days after death, though creditor notice is required once the listed property exceeds $15,000 (§ 473.097). This is the court that decides whether your will was validly executed, which is exactly why the two-witness formality carries so much weight.

Marriage, divorce, and a new child rewrite a Missouri will

If you marry after signing your will and make no provision for the new spouse, that spouse is treated as omitted and takes an intestate share of your estate — unless the omission was intentional and shown in the will, or you provided for them outside it (§ 474.235). Missouri gives similar protection to an after-born or otherwise omitted child, who may take a share as if you had not accounted for them; the safe move is to revisit the will after any birth or adoption rather than rely on the statute to patch the gap.

Divorce cuts the other way and does it automatically. Once your marriage is dissolved, every provision of the will in favor of your former spouse is revoked, and the will takes effect as if the former spouse had died at the time of the divorce (§ 474.420). You do not need to redo the will for the ex to be written out — but you should, so that the gifts and roles that were theirs pass where you actually want them to go.

No handwritten wills, a very narrow oral will, and — new in 2025 — electronic wills

Missouri's baseline is strict: a will must be typed or printed, signed by you (or by someone else at your direction and in your presence), and attested by two competent witnesses who subscribe in your presence, with no publication requirement (§ 474.320). There is no holographic-will exception. The only non-electronic carve-out is the nuncupative (oral) will, and its $500 personal-property ceiling and deathbed conditions make it useless for ordinary planning (§ 474.340).

As of August 28, 2025, Missouri recognizes electronic wills under the Uniform Electronic Wills and Electronic Estate Planning Documents Act (§§ 474.540–474.564). A valid e-will must be readable as text, signed by the maker (or by another in the maker's physical presence), and witnessed by two people in the maker's physical or electronic presence, and it can be made self-proving through a remote online notary (§ 474.550). Because the law is brand new, the cautious route for any will signed today is still a wet-ink signature with two witnesses physically present — the path courts have decades of experience admitting.

Common questions about Missouri wills

Sources

• Mo. Rev. Stat. § 474.310 — Who may make a will
• Mo. Rev. Stat. § 474.320 — Execution and attestation of wills
• Mo. Rev. Stat. § 474.330 — Interested witnesses
• Mo. Rev. Stat. § 474.337 — Self-proving affidavit
• Mo. Rev. Stat. § 474.340 — Nuncupative (oral) wills
• Mo. Rev. Stat. § 474.010 — Intestate succession
• Mo. Rev. Stat. § 474.160 — Elective share of surviving spouse
• Mo. Rev. Stat. § 474.420 — Effect of dissolution of marriage
• Mo. Rev. Stat. § 473.097 — Small-estate affidavit
• Mo. Rev. Stat. § 474.550 — Electronic wills; execution and self-proving
• Missouri Department of Revenue — Estate tax

Who Can Make a Will in Missouri?

You must be at least 18 years old to make a will in Missouri. No statutory exceptions for minors. The testator must be of sound mind and over 18 years of age (Mo. Rev. Stat. § 474.310)

Signing Requirements

Must be in writing. Can be typed, printed, or handwritten. If you are physically unable to sign, Another person may sign in the testator's presence and by the testator's express direction (Mo. Rev. Stat. § 474.320).

Witness Requirements in Missouri

Missouri requires 2 witnesses. Must be competent witnesses at least 18 years old. The testator must sign or acknowledge the will in the presence of two or more competent witnesses who shall attest and sign in the testator's presence (Mo. Rev. Stat. § 474.320).

Interested witnesses: An interested witness does not invalidate the will but the bequest may be limited to the intestate share

Notarization in Missouri

Notarization is not required for a will to be valid in Missouri. Not required for validity; used for self-proving affidavit

Self-Proving Affidavit

Missouri allows a self-proving affidavit, which simplifies probate by eliminating the need for witnesses to testify in court. Testator and witnesses sign a sworn affidavit before a notary public (Mo. Rev. Stat. § 474.337)

Handwritten (Holographic) Wills

Missouri does not recognize holographic wills. Holographic wills are not recognized in Missouri

Electronic Wills

Missouri recognizes electronic wills. Missouri enacted electronic will provisions effective August 28, 2025. Electronic wills must be in an electronic record, electronically signed by the testator, and witnessed

Oral (Nuncupative) Wills

Recognized in limited circumstances: must be made during last sickness or in imminent peril of death, before two competent witnesses. For personal property only, not exceeding $500. Must be reduced to writing within 30 days and proved within 6 months (Mo. Rev. Stat. § 474.340)

How to Revoke a Will in Missouri

In Missouri, a will can be revoked by:

• •Executing a subsequent will or codicil
• •Physical destruction (burning, tearing, canceling, obliterating) by the testator or at the testator's direction and in the testator's presence

Mo. Rev. Stat. § 474.400

Special Provisions in Missouri

Missouri is a separate property/common law state. Surviving spouse has an elective share: one-third of the estate if surviving descendants, one-half if no surviving descendants (Mo. Rev. Stat. § 474.160). Missouri has no state estate or inheritance tax

Relevant Missouri Statutes

• Mo. Rev. Stat. § 474.310 (Who may make a will)
• Mo. Rev. Stat. § 474.320 (Execution of wills)
• Mo. Rev. Stat. § 474.337 (Self-proved wills)
• Mo. Rev. Stat. § 474.340 (Nuncupative wills)
• Mo. Rev. Stat. § 474.400 (Revocation)
• Mo. Rev. Stat. § 474.160 (Elective share)