Michigan's Estates and Protected Individuals Code defines a will as an "instrument that appoints a personal representative, revokes or revises another will, nominates a guardian, or expressly excludes or limits the right of an individual or class to succeed to the decedent's property that is passing by intestate succession," according to Michigan Compiled Laws section 700.1108. A document that does any one of these things may be considered a will in Michigan, as long as it is in a valid will format.
A Michigan will is valid only if it is in writing and signed by the testator and at least two witnesses, according to Michigan Compiled Laws section 700.2502. Michigan law makes an exception for holographic, or handwritten, wills. In Michigan, a will that is signed, dated, and has "material portions" written in the testator's handwriting may be a valid will even if it is not witnessed, according to Michigan Compiled Laws section 700.2502.
A Michigan will may be "self-proved" if it includes a sworn and notarized statement by the testator, or person who made the will, and each of the two witnesses. Section 700.2504 of the Estates and Protected Individuals Code, or EPIC, gives the proper wording for the sworn and notarized statements. Although a Michigan will does not have to be notarized to be valid, the self-proving clauses make probate easier by eliminating the need for the will's witnesses to testify in court to prove the will is valid.
In Michigan, a will can be revoked either by making a new will that says it revokes any current wills or by destroying all or part of a will, according to Michigan Compiled Laws section 700.2507. If the new will does not say it revokes a previous will, the Michigan probate courts will assume the new will revokes the previous will if the new will covers all of the testator's property. The probate court will assume the new will supplements or replaces only part of the previous will if the new will only covers part of the testator's property or only addresses part of what is covered in the previous will such as the name of the personal representative or guardian.