A will or testament is a legal document that expresses a person's (testator) wishes as to how their property (estate) is to be distributed after their death and as to which person (executor) is to manage the property until its final distribution. For the distribution (devolution) of property not determined by a will, see inheritance and intestacy.

Though it has at times been thought that a "will" historically applied only to real property while "testament" applied only to personal property (thus giving rise to the popular title of the document as "last will and testament"), the historical records show that the terms have been used interchangeably. Thus, the word "will" validly applies to both personal and real property. A will may also create a testamentary trust that is effective only after the death of the testator.