Joint ownership of bank accounts — i.e., where more than one person is designated as an owner — is a common form of ownership. It is usually done out of convenience or as a basic form of estate planning to ensure that any funds in the jointly owned bank account pass to a surviving co-owner.
Missouri has a detailed law addressing joint deposit accounts in Section 362.470, RSMo. Among other things, it makes clear that (1) a deposit in a joint account is the property of the joint owners, (2) the interest belongs to the owners and (3) the funds are to be used exclusively for the owners.
Things can become complex and go awry when there is an agreement between the co-owners with respect to how to use the jointly owned funds. “During the lives of the parties the joint interest ‘readily yields’ to the real intention of the parties.” Carroll v. Hahn, 498 S.W.2d 602, 607 (Mo. Ct. App. 1973). As such, agreements between owners of a joint account may be relevant as to how the funds should be used during the owners’ lifetimes.