What Counts as a Valid Amendment
A healthcare power of attorney is one of the most important documents in any estate plan. But life changes. You may want to swap agents, adjust the scope of authority, or add instructions about medical care you did not include the first time. Under Arizona law, any substantive amendment must follow the same formalities as the original document.
An amendment to a health care power of attorney shall meet the requirements of section 36-3221, subsection A, paragraphs 2 and 3 unless the amendment is only made to indicate an agent's change of address or telephone number.
A.R.S. § 36-3222Under A.R.S. 36-3221, that means the amendment must be signed, dated, and either witnessed by at least one adult or notarized. This protects against unauthorized changes to your health care decisions. If someone tries to alter your healthcare instructions without following these steps, the amendment is not valid.
The Address and Phone Number Exception
The statute carves out one practical exception. If the only change is your agent's mailing address or phone number, you do not need a witness or notary. This makes sense because contact information changes often. Requiring a formal process for a new phone number would create unnecessary friction.
If you are changing who serves as your agent or modifying what medical decisions they can make, the full signing requirements apply. A mental health care power of attorney follows the same amendment rules. When changing mental health care powers granted to your agent, the formal process is required. When in doubt, follow the formal process. It takes a few minutes, and it removes any question about whether the change is legally valid.