pen and letter

Missouri Will Requirements: What Makes a Will Legally Valid?


Lawyer is shaking hands with the client

Too many Missouri residents go without a will, or try to do one on their own. There are countless websites that will let you do a “free will” or one that seems really cheap. Unfortunately, these are usually created by non-lawyers, often from out-of-state. They often fail to meet the basic legal requirements of a valid Missouri will. So, what are the legal requirements to ensure your will is valid? 

The estate planning attorneys at Mark Harford Law help you create a valid will and build a comprehensive estate plan that makes it truly effective. Let us get started for you.  

Basic Legal Requirements for a Valid Missouri Will

Missouri law sets out several core requirements that every will must meet. These rules apply whether the will is simple or complex, handwritten or typed.

To be legally valid in Missouri, a will must:

  • Be made by someone 18 or older
  • Be created by a person of sound mind
  • Be in writing
  • Be signed by the testator (the person making the will)
  • Be witnessed by two competent witnesses who sign in the testator’s presence

If any of these elements are missing, the will may be challenged or rejected by the probate court.

The Testator Must Be of Sound Mind

Missouri requires that the person making the will understands:

  • The nature and extent of their property
  • The people who would naturally inherit from them
  • The legal effect of signing a will

This standard is not as strict as many people assume. A person can have medical conditions, memory issues, or even a diagnosis of dementia and still have the legal capacity to make a will, as long as they meet the basic understanding required at the time of signing.

The Will Must Be in Writing

Unlike some states, Missouri will not recognize oral wills. It has to be written or typed in some fashion. It must also meet all of the other requirements. Missouri does not allow unwitnessed handwritten wills.

Signature Requirements

The testator has to sign the will. If for some reason they’re unable to sign it themselves, they have to tell someone else to sign it for them. If that happens, the person signing has to do it because the testator told them to, and do it in front of the testator.

Witness Requirements in Missouri

Missouri requires two competent witnesses to sign the will. These witnesses must:

  • Be present when the testator signs or acknowledges the will
  • Sign the will in the testator’s presence
  • Be at least 18 years old

Self-Proving Affidavits

Missouri does allow a self-proving affidavit. This is a notarized statement that is signed by the testator and witnesses. It helps move the will through probate more quickly, because the probate court does not have to find the witnesses later to verify that the will is authentic.

A will without a self-proving affidavit is still valid, but it could take longer to go through probate. 

What Happens If a Will Doesn’t Meet Missouri’s Requirements?

If the will doesn’t meet the legal requirements, it could be invalidated. Then, all the assets are distributed through Missouri’s intestacy laws. This might lead to:

  • Unintended heirs receiving property
  • Excluded relatives inheriting by default
  • Delays and increased legal costs
  • Family disputes or litigation
Lawyer is holding judge's gavel

Updating or Revoking a Missouri Will

A valid will remains in effect until it is replaced or revoked. Missouri allows a will to be revoked by:

  • Creating a new will
  • Physically destroying the old will
  • Making a written revocation

If you make significant life changes, it’s wise to review your will to ensure it still reflects your intentions.

Get Help Creating a Valid Will in Missouri

Drafting a will is more than just writing your thoughts on some paper. There are specific legal requirements you have to follow. Failure to do so could mean your will is wholly unenforceable. 

Let the dedicated estate planning attorneys at Mark Harford Law help you. Contact us today for a consultation.