If a decedent (person who is deceased) has real property or tangible personal property in a state other than the state where the decedent lived at the time of death (primary residence or domicile), an ancillary probate proceeding in the other state where the property is located will probably be necessary to transfer title to the property—unless, for example, the decedent took steps to transfer title to the property before death. After the domiciliary probate process is initiated in the state of the decedent’s primary residence, the executor or administrator of the estate may open an ancillary probate proceeding in the state where the property is located.

The ancillary probate is usually an abbreviated process that relies in whole or in part on the domiciliary probate court’s admission or acceptance of the will for probate. Thus, any challenges to the validity of the will generally must be made in the domiciliary probate court. And once the domiciliary probate court admits the will to probate and grants the executor or administrator authority to act on behalf of the estate (letters testamentary, letters of administration), the executor may file a copy of the will and the letters testamentary or letters of administration in the ancillary probate court. The ancillary probate court will then admit the will to probate in that state as a foreign will, giving the executor or administrator the authority to transfer or sell the property in the ancillary probate state.

In Michigan, if a decedent owned real estate or tangible personal property in a state other than their state of domicile at the time of death, an ancillary probate proceeding is typically required in the state where the property is located to transfer title. This is necessary unless the decedent arranged for the transfer of title prior to death. After starting the primary probate process in the state of the decedent's domicile, the executor or administrator can initiate an ancillary probate in the state with the other property. Ancillary probate in Michigan is a streamlined process that often depends on the primary probate court's actions, such as admitting the will to probate and issuing letters testamentary or administration. Challenges to the will's validity are generally handled in the domiciliary state. Once the primary probate court admits the will and grants authority to the executor, they can present these documents to the ancillary probate court in Michigan. The Michigan court will recognize the will as a foreign will and authorize the executor or administrator to manage the property within the state.