Missouri Wills: The Real Standards Behind a Legally Binding Last Will and Testament

Who this is for: Missouri adults who want to write a will and need to know the exact legal standards before starting. What it covers: Missouri will basics from the ground up: legal requirements, witness rules, what holographic wills mean in Missouri, and how wills interact with other estate planning documents. Why it matters: Missouri wills must hit every statutory mark or the court treats the decedent as having no will at all. Patrick Nolan is an estate planning attorney at Nolan Law Firm in Kirksville, Missouri.

Quick Answer: Under RSMo 474.320, a valid Missouri will requires: testator must be 18 or older and of sound mind, will must be in writing (typed or handwritten), testator must sign, and two competent adult witnesses must sign in the testator presence. Missouri does not allow unwitnessed holographic wills. A notarized self-proving affidavit is optional but recommended. Without a valid will, RSMo 474.010 intestate succession controls the estate.

Missouri Law on What Makes a Will Hold Up

A last will and testament cuts straight to the heart of what happens after you’re gone. In Missouri, there’s no room for guesswork; state statutes lay out step-by-step directions. Get one detail wrong, and the state takes over. Your property could be chopped up by default intestacy rules, nothing close to the way you wanted.

The rules themselves—RSMo § 474.320 if you want to get technical—don’t leave loose ends. Missouri spells out who can draft a will, who counts as a legitimate witness, and how every signature must land on the page. You either hit every requirement or risk losing control of your own estate.

Who Can Write a Will: Age and State of Mind

If you’re at least 18, or younger but emancipation has already split you from parental authority, you can legally make a will in Missouri. Still, age alone isn’t enough. The law insists on “sound mind.” Those words do most of the heavy lifting. If you can’t understand you’re making a will, can’t name your own assets, or don’t know who you’re leaving things to, the whole document comes apart. Probate court doesn’t blink—they’ll throw it out for lack of capacity.

Writing or Talking: What Counts as a Will

Only what’s on paper counts in Missouri. Some states jump through hoops and accept deathbed declarations or “nuncupative” wills. Not Missouri. Your wishes need hard ink—typed or handwritten, either way, it must exist as a real, physical document. But here’s the catch: even if you handwrite every word (the so-called “holographic will”), you still need proper witnesses. Missouri doesn’t play fast and loose like states that let a handwritten note slide through without someone else in the room.

Who Has to Watch: Missouri Witness Rules

When the moment comes to sign, Missouri says you need two disinterested people in front of you. They have to see you sign—or you can acknowledge your signature, but both must be present at the same time. You can’t do half now, half later. And “disinterested” matters. If one of your witnesses gets anything under your will, Missouri doesn’t void the whole document, but that person could sacrifice their share unless there are two other, uninvolved witnesses as backup. For a clean process, use folks with nothing to gain.

Getting That Signature Right

You—the testator—are the one signing, unless you’re physically unable, and then only someone who you direct, in front of witnesses, can sign for you. Their name, your intent, all of it right there for everyone to see. And—contrary to common rumor—a notary isn’t required. Missouri doesn’t care if a seal’s stamped on the page. That said, if you want to avoid dragging your witnesses into court, you can attach a “self-proving affidavit” with a notary. That document tells the probate judge you were of sound mind and everybody followed the rules. Probate goes faster—less hassle for your executor.

Key Factors When Crafting a Will in Missouri

The “Self-Proving” Shortcut

A self-proving will is built for speed. It adds an affidavit—a sworn statement in front of a notary—where everybody confirms the rules were followed. It’s not required, but it keeps your witnesses from having to show up in court later. Missouri calls that out in RSMo § 474.337. For most families, that extra affidavit keeps arguments to a minimum and probate wheels turning.

Choosing Who Stands By

Pick witnesses who are adults and have zero stake in your estate. Bring in a relative or someone who inherits under your will, and you might end up explaining yourself to a judge—or watching their share get taken away. Missouri does allow interested witnesses, but only if you have two who aren’t gaining anything. Best practice: don’t tempt fate. Find outsiders.

How to Change or Cancel Your Will

Any testator with full mental capacity can revoke their will at any time. Burn it, tear it, or write a new one that clearly revokes the old. But scribbles or margins don’t count unless they’re signed and witnessed in line with state law. If you need big changes—naming a new executor, adjusting inheritances, adding or removing people—it’s cleaner to make a fresh will and leave no debate. The courts respect paperwork, not post-it notes.

If the Paperwork Isn’t Right

Missouri doesn’t forgive broken rules. Miss the mark on signatures or witnesses, a judge will declare your will invalid, and everything falls under the standard intestacy pecking order: spouse, kids, then on down the bloodline. Technicalities matter. Lose sight of the legal steps, and your wishes will die with you.

Where to Store the Original

Once you sign, put your will where it’s both safe and findable. A home safe, attorney’s office, even the county probate court (though that’s an optional filing). Tell your executor exactly where it lives. Make no mistake—Missouri probate courts want the original, not a photocopy. If the original’s destroyed, the process grinds to a halt.

Practical Issues: Missouri FAQs and Real-World Hurdles

Wills from Other States

Missouri will honor a will from out of state—so long as that will met the law wherever it was made. Still, differences crop up: weird signature rules, witnesses, or property rights can trip things up. If you move to Missouri, run your old will by a Missouri attorney. Better safe than sorry.

Handwritten Wills and the Rules

A plain handwritten will only has teeth if two disinterested witnesses sign on. Write out what you want, sign it, but skip the witnesses? Won’t hold water. Missouri won’t let even an obviously genuine note skip past the witness requirement, no matter how clear your intent.

Does a Will Need a Notary?

No notary is legally necessary to create a valid Missouri will. The only advantage is if you want it “self-proving.” In that case, all parties sign an affidavit with a notary public. That extra step smooths probate. Skip it, and your witnesses might end up called to testify in court after you die.

Out-of-State Executors: Permitted or Problem?

You can pick a non-resident to be your executor, but Missouri may ask them to post a bond or appoint someone local for legal notices—unless they’re immediate family. Naming someone nearby, or at least adding a co-executor who lives in Missouri, sidesteps red tape.

Do Married Couples Need Separate Wills?

Missouri lets spouses prepare individual wills. But if you hold property jointly or with rights of survivorship, that asset likely won’t pass under your will at all. There are also rules to protect a surviving spouse who gets left out—they can claim an “elective share” under the law. And if you’re aiming for something unusual, like excluding a spouse or kids, careful planning with legal advice isn’t just smart, it’s necessary.

Why the Details Matter When Making a Missouri Will

Estate planning is supposed to solve problems, not hand out new ones. Skipping a rule here—a witness, a signature, a missed instruction—can turn the next chapter for your family into a court fight. Get it right from the start by facing the requirements with clear eyes, not wishful thinking.

DIY forms may look like a shortcut, but they skip the lived realities—second marriages, uneven families, farms, and real loss. Get real legal help for what matters. A Missouri will done right is built to last and to stand up in the face of doubt. You only get one clean shot.

Frequently Asked Questions: Missouri Will Basics

What does it take to write a valid will in Missouri?

Missouri law under RSMo 474.320 requires four things: the testator must be at least 18 and of sound mind, the will must be in writing, the testator must sign it, and two competent adult witnesses must sign in the testator presence during the same signing event. That is the complete list. No notary is required, though a self-proving affidavit signed before a notary speeds up probate after death.

Are holographic (handwritten) wills valid in Missouri?

Missouri does not recognize unwitnessed holographic wills. A handwritten will in Missouri must still be signed by the testator and witnessed by two competent adults, exactly the same as a typed will. This differs from states like California or Texas where a fully handwritten and self-signed will may be valid without witnesses. In Missouri, no witnesses means no valid will, regardless of how clearly the document expresses the testator wishes.

What happens in Missouri if you die without a valid will?

If you die without a valid will in Missouri, you are considered intestate and your estate is distributed under RSMo 474.010. The statute follows a strict hierarchy: surviving spouse and children come first, then parents and siblings, then more distant relatives. If no eligible relatives are found, the estate escheats to the state of Missouri. Your friendships, promises, and preferences carry no legal weight without a valid will.

Can I update or revoke my Missouri will after signing it?

Yes. A Missouri will can be updated at any time by executing a new will or a formal amendment called a codicil. Both must meet the same signing and witnessing requirements as the original will. A will can also be revoked by physically destroying it with intent to revoke. Under Missouri law, divorce automatically revokes provisions in favor of an ex-spouse, and remarriage may affect prior wills as well.

How does a Missouri will interact with a living trust?

A will and a living trust serve different functions in a Missouri estate plan. A will controls probate assets and goes through the court process. A funded living trust controls assets transferred into it and avoids probate entirely. Most complete Missouri estate plans include both: a trust for major assets and a pour-over will to capture any assets left outside the trust at death and pour them in. The will and trust work together, not in competition.

Does a Missouri will control what happens to my retirement accounts?

No. Retirement accounts (IRA, 401k, pension) pass to named beneficiaries directly, outside of probate and outside the control of your will. If you name your estate as beneficiary or fail to name one, the account may be forced into probate and lose tax advantages. Keeping beneficiary designations current and coordinated with your will is an essential part of Missouri estate planning.