Neither a notary nor witnesses is required, but typically you want two witnesses and a notary. The reason is that prenuptial agreements often affect real estate (like how the house will get divided in a divorce), and Florida law requires that any contract that affects real estate have two witnesses and a notary. If your prenuptial only, for example, says that no one gets alimony, it doesn't affect real estate, and the notary and witnesses would be recommended but not required. Having witnesses and a notary help prevent a person from denying they signed.
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Rose is right and right as rain. It is best to have the agreement witnessed and notarized but not required. You do need an attorney for a pre nuptial agreement to make sure that there are no invalid provisions.
R. Jason de Groot, Esq., 386-337-8239
You are flirting with disaster if you do not have 2 witnesses and a notary. When it comes time to enforce the agreement, the other side with allege that their signature was forged. Best practice if for any contract to 1) be in writing and 2) signed in the presence of two witnesses and a notary. The notary can technically be one of the witnesses. A will or trust on the other hand requires that the notary not be one of the witnesses.
These comments are not intended to create any attorney-client relationship and the information provided is based only upon the limited facts given. It is recommended that you consult with counsel of your choosing.