The term pour over trust refers to a revocable, living trust which is used to plan for the eventual incapacity of the donor. The assets placed in the trust remain there until the death of the donor, at which time they are distributed to the donor's heirs.
Also referred to as a pourover trust, a pour over trust gets its name from the process that occurs when the donor passes away. At that point in time, the trust's assets will "pour-over" into their estate and be distributed to the donor's heirs.
Normally used to plan for death or incapacitation, the donor provides assets to the trust and oftentimes acts as trustee too. The donor may continue to place assets in the trust, and they will remain there until the donor passes away. If the donor becomes incapacitated, a co-trustee will assume responsibility to protect the trust's assets, and will eventually distribute them upon the death of the donor. This is the primary advantage of a pour over trust. They relieve the donor's family of the responsibility for making what will be difficult decisions when the donor can no longer care for themselves.
Pour over trusts are revocable, and they can be revoked if the donor requires additional assets. For this reason, donors are normally conservative when placing assets into the trust. Another advantage of this type of trust has to do with privacy. Unlike a testamentary trust, pour over trusts are not made public.