How to Write a Will in Missouri (2026 Guide)

This is general legal information for Missouri, not legal advice. Will laws change, and specific situations can have exceptions. For any complex case, consult a licensed attorney in Missouri.

Why Having a Will Matters

A will is the simplest, clearest way to say what happens to your property, your minor children, and your affairs after you die. Without one, you die "intestate" and Missouri’s default inheritance rules (called intestate succession) take over. Those rules are rigid and generic — they do not know your relationships, your intentions, or the people you care about most. They follow a fixed formula.

The cost of skipping a will is not hypothetical. It plays out the same way in Missouri as everywhere else: unmarried partners locked out, stepchildren with nothing, pets in shelters, court-appointed administrators, family disputes over items and money, and a probate process that is slower, messier, and more expensive than it needed to be. Whatever you own — even if you think it’s "not much" — someone will have to deal with it after you’re gone. A will decides whether that someone is you or a judge.

A simple Missouri will takes about ten minutes to draft using a free tool and costs nothing. You can start drafting yours now. The rest of this guide walks you through what makes a will legally valid in Missouri and how to avoid the technical mistakes that most commonly cause wills to be thrown out.

Missouri Will Requirements at a Glance

• Minimum age: 18 years old (No statutory exceptions for minors)
• Written form: Must be in writing. Can be typed, printed, or handwritten
• Witnesses required: 2
• Notarization: Not required for a standard signed will
• Self-proving affidavit: Yes — recommended, it speeds up probate later
• Holographic (handwritten) wills: No
• Electronic wills: Yes

Testamentary Capacity

The testator must be of sound mind and over 18 years of age (Mo. Rev. Stat. § 474.310)

Signature Requirements in Missouri

You must personally sign the will. Missouri does allow proxy signing in specific cases: 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

Presence rules: 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

The safest approach in every state, including Missouri, is to use witnesses who are adults, not beneficiaries under the will, and not the person you’ve named as executor. This avoids any question about whether a witness’s inheritance could be "purged" for being an interested party.

Notarization and Self-Proving Affidavits

Missouri does not require a will to be notarized to be valid. A signed and witnessed will is enough. Not required for validity; used for self-proving affidavit

Missouri does allow a self-proving affidavit, which is a short notarized document attached to the will where you and your witnesses swear under oath that everything was signed properly. It is optional, but it is strongly recommended — a self-proving affidavit means the probate court can admit the will without having to contact your witnesses later. Testator and witnesses sign a sworn affidavit before a notary public (Mo. Rev. Stat. § 474.337)

Holographic, Electronic, and Oral Wills in Missouri

Holographic (handwritten) wills: Not recognized in Missouri. A valid will must be typed or printed and signed in front of witnesses.

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

Nuncupative (oral) wills: Recognized in Missouri under very limited circumstances. 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 or Update a Missouri Will

If you already have a will and want to change it, Missouri recognizes these revocation methods: 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

The cleanest approach is to draft a new will that starts with the sentence "I revoke all previous wills and codicils," then sign it with the proper witnesses. Destroy old copies when you do. Small updates can technically be done by codicil (a formal amendment), but a fresh will is usually easier to read and harder to contest.

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

Step-by-Step: Writing a Valid Missouri Will

1. Take inventory. Bank accounts, vehicles, property, valuables, digital assets, pets.
2. Decide who gets what. Be specific for items that matter (names, addresses, account identifiers). Use a residuary clause ("everything else goes to...") to catch anything you forget.
3. Name an executor. The person who handles your estate. Pick someone trustworthy, organized, and likely to outlive you. Name a backup too.
4. Name a guardian for minor children if you have kids under 18. This is the single most important reason for a will if you’re a parent.
5. Draft the document. Our free drafting tool generates a Missouri-specific will in about 10 minutes, with all the correct clauses in the correct order.
6. Print the will. Don’t rely on a digital copy for signing.
7. Sign in front of 2 adult witnesses who are not named as beneficiaries. You all need to be in the same room at the same time. You sign first, they sign while watching.
8. Sign the self-proving affidavit in front of a notary. This is optional but speeds up probate later.
9. Store it somewhere findable. A fireproof home safe is the standard choice. Tell your executor where it is.
10. Review every few years and after major life events (marriage, divorce, new child, moving out of Missouri, major asset changes).

Common Missouri Will Mistakes to Avoid

• Wrong number of witnesses. Missouri requires 2. More is fine; fewer invalidates the will.
• Using a beneficiary as a witness. Can cause the beneficiary’s share to be "purged" (forfeited).
• Not signing in the witnesses’ presence. The signing has to happen as a ceremony, with everyone in the same room.
• Forgetting a residuary clause. Without it, anything you didn’t specifically mention falls into intestate succession.
• Storing the will where nobody can find it. An unfindable will is the same as no will.
• Not updating after major life events. An ex-spouse named in an old will can still inherit in some situations.

Need to Check Details?

You can also read the full Missouri will requirements and the Missouri estate planning guide for background on intestate succession, probate, and related topics.

Start Your Missouri Will Now

The easiest way to get a valid Missouri will done today is our free drafting tool. It walks you through the questions, generates a Missouri-specific document with the correct clauses, and gives you signing instructions tailored to Missouri’s requirements. No account, no cost, nothing stored on our servers. You’ll have a draft ready in about ten minutes.

Whatever you decide, decide. A simple will is one of the most meaningful things you can leave the people you love — and it’s one of the easiest things to put off until it’s too late.