Lawyers, accountants and financial advisors have long promoted joint tenancy and joint bank accounts as a quick and easy estate-planning tool. The advantage: no probate fees. This is because of a legal principle called survivorship; it means that money and property held jointly automatically become the property of one joint owner upon the death of the other.

The pitfall, however, lies in another legal concept known as the presumption of resulting trust. When applied to joint property, this concept forces the recipient of any money or property through survivorship to prove that the deceased intended for that asset to be a gift to them. If the recipient can’t provide proof, the asset is forfeited to the deceased’s estate and distributed among the beneficiaries. This applies whenever money or property is transferred from a parent to an adult child.

Where a parent has failed to make his or her intentions clear, the question will often arise as to whether the parent intended the child to receive the asset as a gift or whether the parent intended for the asset to be distributed to the other children or beneficiaries of the estate. Such uncertainty can lead to costly litigation and bitter disputes among family members.

How to avoid this pitfall: make your intentions clear in your will. While keeping assets jointly owned has its uses as an estate planning tool, it is no substitute for a comprehensive and up-to-date will, ensuring that all of your family members, friends, and most importantly, the court, understand to whom you intended to give a gift of money or property. There are few things which breed family disputes and even litigation more readily than uncertainty – so don’t leave any in your estate!