A person who makes a will (a testator) may update or revise the will at any time during their lifetime if the testator has the required mental capacity (is of sound mind) and the document is executed or signed with the required formalities (such as witnesses and signatures), as provided by the state’s laws.

There are generally two ways to update a will—execute a new will (usually the best option) with the required witnesses, signatures, and other formalities—or execute a codicil (a supplement to an earlier will), with the required witnesses, signatures, and other formalities, as provided by the state’s laws.

Laws regarding the use of codicils and the required formalities for wills and codicils vary from state to state and are usually located in a state’s statutes—often in the estates code or probate code.

A testator who updates their will by executing a new will should usually destroy the previous will to avoid questions regarding which will reflects the testator’s true intent and to avoid competing wills being offered for probate (recognition by the court).

In Alabama, a testator has the right to update or revise their will at any time as long as they have the mental capacity to do so and adhere to the state's legal formalities. To execute a new will or a codicil (an amendment to the will), the testator must follow specific requirements, such as having the document witnessed and properly signed. These formalities are outlined in Alabama's statutes, particularly in the Alabama Code Title 43 (Wills and Decedents' Estates). When a testator chooses to execute a new will, it is recommended that they destroy any previous versions to prevent confusion and ensure that only the most recent will is recognized during probate proceedings. If a codicil is used, it must also meet the same formalities as a new will to be legally valid.