A life interest is a form of right, usually under a trust, which lasts only for the lifetime of the person benefiting from that right. A person with a life interest is known as a life tenant. A life interest ends when the life tenant dies.
An interest in possession trust is the most common example. In a typical case, the life tenant receives all the income from the trust for the rest of his or her life. On their death, the trust comes to an end, and the capital of the trust is paid to another person, as specified by the trust document.
A life estate is an ownership interest in property which lasts for the life of the beneficiary. The owner of a life estate has the right to possession of the property, and may use it as any other owner, but with a duty to avoid waste of the property value affecting parties with a future interest.