A prenuptial (meaning "before marriage" ) agreement is by definition done before a marriage. You could enter into a postnuptial ("after marriage") agreement doing the same thing.
Daniele C. JohnsonDivorce / Separation LawyerAtlanta, GAGA licensed ·
Yes. However, it is called a postnuptial agreement instead of prenuptial. It would still have the same binding effect as if it was signed before the marriage.