Letters testamentary are governed by state probate laws, which vary by state. When a court appoints an executor of administrator of a deceased's estate, the administrator or executor will receive a document called “Letters of Testmentary” or “Articles of Administration” which will be issued by the court, outlining the administrator’s or executor’s authority and responsibility. Before money or assets are transferred to the executor or administrator, certified copies of the letters are often required by banks and other financial institutions, the federal government, stock transfer agents or other courts.
