A "self-proving" will is one that comes with something extra: a sworn statement from the witnesses who watched the will-maker sign the will. In many states, probate courts will accept this statement as evidence that the will is valid. That eliminates the need, after the will-maker has died, for the witnesses to come to court and testify about watching the will being signed.
If there’s a dispute about the validity of a contract or a lease, the people whose signatures are on the document can take the stand and testify about whether or not their signature is genuine. But because a will doesn’t have any legal effect until the person who signed it has died, that’s not possible in probate court. There has to be another way to prove that a will is valid.
That’s why witnesses are crucial to proving the validity of a will. After someone dies, and the will is submitted to the probate court, the court requires testimony from two adult witnesses that they:
Witnesses can usually convey their knowledge to the court either in the form of live testimony or in sworn written statements (affidavits), signed in front of a notary public.
The only exception to the witness requirement is that in some states, wills that are written and signed entirely in the will-maker’s handwriting, but not witnesses, can be admitted to probate. In that case, the proof that the document is valid comes from people who testify about the will-maker’s handwriting and the circumstances under which the will was written.
It can be troublesome (or impossible) to find the witnesses to a will and get them to either come to court or sign affidavits describing how they watched the will being signed—especially if the will was written many years before the death, as is common.
That’s where the self-proving affidavit comes in. If a sworn statement from the witnesses is attached to the will, the witnesses won’t have to come to court and testify.
In most states, the statement must be notarized—that is, signed in front of a notary public, who also signs the document and stamps an official seal on it. A few states, however, allow witnesses to sign a statement "under penalty of perjury." A notary doesn’t have to be present, but the witnesses state that they are making a truthful statement—and that if they aren’t, they realize they are committing the crime of perjury, or lying under oath.
A typical self-proving affidavit looks something like this:
We, _______ and_______, the witnesses, sign our names to this instrument, being first duly sworn, and do hereby declare to the undersigned authority that the testator signs and executes this instrument as [his] [her] will and that [he] [she] signs it willingly (or willingly directs another to sign for [him] [her] ), and that each of us, in the presence and hearing of the testator, hereby signs this will as witness to the testator's signing, and that to the best of our knowledge the testator is 18 years of age or older, of sound mind, and under no constraint or undue influence.
Typically, witnesses sign the self-proving affidavit at the same time that they sign the will itself, immediately after watching the will-maker (called by the legal term "testator" in the sample statement) sign it. But many courts will accept an affidavit that was signed later.
Not every state allows for self-proving wills. In the District of Columbia, Maryland, Ohio, and Vermont, the self-proving option is not available.
In California, Indiana, and New Hampshire, it’s not necessary to have a separate affidavit for witnesses to sign. The will itself can include a statement that under penalty of perjury, the witnesses state that to the best of their knowledge, the will-maker was old enough to make a will, mentally competent to do so, and not under undue influence. That’s enough to make the will self-proving.