You don't need to have your last will and testament notarized to make it legal. However, in many states signing an affidavit with your witnesses in front of a notary public can simplify the court procedures necessary to prove your will is valid.
Locating a Notary
Notaries often are found at courts, post offices and banks. If your bank has a notary, it may offer the service free of charge as a courtesy. Traveling notaries will come directly to you for a fee. The cost of having documents notarized varies. For example, in Massachusetts the maximum cost is $1.25 per signature. In California, the standard fee is $10 per signature.
You'll need to bring your identification along with the document you are having notarized. The notary won't be notarizing your actual last will and testament. Instead, you'll need to complete a self-proving affidavit, which is a sworn statement signed by you and your witnesses that attests the will is valid. State laws vary on the specific language requirements, but basically the document must state the witnesses affirm you voluntarily executed the will. You and your witnesses must wait to sign the document until you are in the presence of the notary. You'll typically sign first, followed by your two witnesses. Keep the affidavit with your will, but do not staple the documents together.