Definition - What does Trust Merger mean?
A trust merger is a situation where the beneficiary of a trust, and the trustee of the same trust, are one person. When this happens, the trust ceases to exist. This is because there is no need for the trustee to manage assets on behalf of the beneficiary if the trustee is the beneficiary.
Justipedia explains Trust Merger
A situation where a trust merger could take place would be if a grandfather sets up a trust for his grandson and then names the grandson's father as the trustee. If both the grandfather and the father die, and the grandson was a backup trustee, then he would simultaneously be the beneficiary and the trustee. So, in this case, a trust merger would occur. Once the trust merger occurred, then the trust would cease to exist because it would have no purpose. The assets would simply become the full property of the grandson.