---
type: Concept
title: Missouri Self-Proving Affidavit
description: What a self-proving affidavit does for a Missouri will and how to execute it correctly.
resource: https://nemolegal.com/missouri-self-proving-affidavit-what-it-does-and-how-to-get-it-right/
tags: [wills, self-proving-affidavit, probate, notary, missouri]
timestamp: 2026-06-22
jurisdiction: Missouri
author: Patrick Nolan
---

# Summary
A self-proving affidavit is a notarized statement, signed by the testator and witnesses, attached to a Missouri will. It does not change who inherits and does not replace any will requirement; it is legal insurance that lets the probate court accept the will without tracking down witnesses. Without it the will is still valid, but admission to probate is slower and more contested.

# Quotable Q&A
**Q: What does a self-proving affidavit do in Missouri?**
A: It is a notarized statement, signed by the testator and witnesses, that confirms the will was executed properly. With it, the probate court can accept the will at face value without locating the original witnesses years later. It is optional, but it spares the family delay and expense.

**Q: Is a self-proving affidavit required for a Missouri will?**
A: No. A Missouri will is valid without one. The affidavit is legal insurance; it changes nothing about who gets what and does not replace the writing, signature, or two-witness requirements.

**Q: What if my will has no self-proving affidavit?**
A: The will can still be admitted, but the court will usually need a witness to appear or sign an affidavit. If witnesses have died or cannot be found, the judge may demand extra evidence. You can fix it by re-executing the will or drafting a new one with the affidavit.

# What It Requires and How It Goes Wrong
Before the affidavit matters, the will must stand on its own: testator 18 or older and of sound mind, in writing, signed by the testator, and witnessed by two competent adults. The affidavit then needs an acknowledgement from the testator and witnesses under oath, proper notarization, and language that tracks Missouri's statutory model. The common failures are notary mistakes such as a missing seal or expired commission, piecemeal signings where people sign at different times, a mismatch between the witnesses on the will and the affidavit, and generic forms from other states whose language does not fit Missouri.

# The Clean Way to Execute
The firm's field method is to use Missouri-specific documents, pick solid disinterested adult witnesses who could be found later, and gather the testator, two witnesses, and a notary in one room at one time. The will is signed first, then the affidavit. The attorney or notary confirms capacity privately to guard against undue influence, and the executed original is stored somewhere safe but retrievable, with the personal representative knowing where it lives.

# Decision rule
If you want to spare your family the burden of locating witnesses after your death, then sign a Missouri self-proving affidavit before a notary at the same sitting as the will. If your existing will lacks one, then re-execute the will or draft a new one with the affidavit rather than adding informal notes.

# Related
- [Wills and Will Requirements](/okf/estate-planning/wills.md)
- [Missouri Will Requirements](/okf/wills-execution/will-requirements.md)
- [Witnesses for Missouri Wills](/okf/wills-execution/witnesses-for-wills.md)
- [How to Make a Will in Missouri](/okf/wills-execution/how-to-make-a-will.md)
- [RSMo Chapter 474 (Wills)](/okf/authorities/missouri/rsmo-474-wills.md)
- [About Nolan Law Firm](/okf/firm.md)