A letter of testamentary—also known as letters testamentary—is a written order from a probate court approving the appointment of an executor under a will and authorizing the executor to administer the will and the decedent’s estate—including collecting amounts due to the estate, paying any outstanding debts of the estate, and distributing the assets of the estate in accordance with the provisions of the will.

Banks, brokerages, and mortgage and title companies rely on the court-ordered authority of the executor—as demonstrated by a letter of testamentary—when transferring ownership and control of assets in the testator’s estate.

When a deceased person (decedent) dies without a will (intestate) or the decedent’s will is found to be invalid by the probate court, the court may appoint an administrator to manage the estate, assets, and liabilities of the decedent. The administrator must be qualified or approved by the court and in some instances may be required to post a bond to secure the assets of the estate.

Upon appointment of an administrator by the probate court the court may issue letters of administration that authorize the administrator to administer the decedent’s estate by collecting amounts due to the estate, paying any outstanding debts of the estate, and distributing the assets of the estate in accordance with the state’s intestate succession laws.

Laws and procedures vary from state to state but an administrator—and the administrator’s administration of the estate—may be supervised or unsupervised by the probate court and may be with or without a bond required from the administrator.

In Texas, a letter of testamentary is a legal document issued by a probate court that grants an executor the authority to manage the estate of a deceased person as specified in their will. This includes the power to collect debts owed to the estate, pay the estate's debts, and distribute the remaining assets according to the will's instructions. Financial institutions and other entities require this document to ensure they are transferring assets to the authorized individual. If a person dies intestate (without a valid will), or if the will is deemed invalid, the court may appoint an administrator for the estate. The administrator is tasked with similar responsibilities as an executor but must act in accordance with Texas's intestate succession laws. The court may issue letters of administration to authorize the administrator's actions. Whether the administration of the estate is supervised by the court and whether a bond is required from the administrator can vary. In Texas, the probate process, including the issuance of letters testamentary or administration, is governed by the Texas Estates Code.