Almost any adult can serve as your health care agent, as long as they are at least 18 years old and mentally competent. A health care agent (also called a health care proxy) is the person you legally designate to make medical decisions on your behalf if you become unable to speak for yourself. You don’t need to choose a family member, and the person doesn’t need any medical or legal background.
Basic Eligibility Requirements
The core requirement across most states is simple: your health care agent must be at least 18 years old. Beyond that, the person needs to be of sound mind, meaning they can understand medical information and communicate decisions to your care team. There’s no requirement for any specific education, certification, or professional qualification.
You can choose a spouse, adult child, sibling, close friend, neighbor, religious leader, or anyone else you trust. Domestic partners, unmarried partners, and people with no biological or legal relationship to you are all eligible. The law does not limit this role to family members.
Who Cannot Serve as Your Agent
While the rules vary by state, certain categories of people are generally restricted or outright prohibited from acting as your health care agent. The American Bar Association recommends avoiding the following:
- Your health care provider or their spouse or employee. A doctor currently treating you has a potential conflict of interest. Texas law, for example, explicitly bars your health care provider and their employees from serving as your agent unless that employee is a relative.
- The owner or operator of your care facility. If you live in a nursing home, assisted living facility, or similar residential setting, the people who run or work at that facility generally cannot be your agent. Again, some states make an exception if the person is a relative.
- A government employee financially responsible for your care. This applies to people working for agencies that fund or oversee your treatment, such as Medicaid caseworkers in certain roles.
- A professional evaluating your decision-making capacity. If someone has been appointed to assess whether you can make your own choices, they cannot simultaneously serve as the person making those choices for you.
- Your court-appointed guardian or conservator, in some states.
- Someone already serving as agent for 10 or more other people. This prevents one person from being stretched too thin to meaningfully advocate for you.
The common thread in these restrictions is conflict of interest. The law aims to ensure that the person making your medical decisions has no financial stake in your care and no competing loyalties.
Friends and Non-Family Members
Choosing a friend or someone outside your family is completely legal in every state. In some situations, a close friend is actually a better choice than a relative. What matters most is that the person understands your values, can handle stressful conversations with medical staff, and will follow your wishes even when those wishes are difficult to carry out. A sibling who lives across the country and avoids hard conversations may be a weaker choice than a trusted friend who lives nearby and knows exactly how you feel about life-sustaining treatment.
If you don’t have anyone in your personal life who fits the role, some states allow you to appoint a professional fiduciary or patient advocate. These are paid professionals who specialize in managing health care decisions, though availability and regulations vary by state.
Naming a Backup Agent
Most states allow you to name one or more alternate (successor) agents in your health care proxy form. This is a practical safeguard. If your primary agent is unreachable, becomes incapacitated, or is unwilling to serve when the time comes, the backup steps in automatically without any need for a court proceeding. Naming at least one alternate is strongly recommended.
Co-agents, where two people share decision-making authority at the same time, are allowed in some states but can create problems. If your two co-agents disagree on a treatment decision, medical providers may not know whose instructions to follow. Most estate planning attorneys advise naming a single primary agent and one or two alternates in order of priority.
Who Can Witness the Document
Naming a health care agent requires a signed legal document, and most states require one or two witnesses. The witnessing rules have their own set of restrictions, which are separate from agent eligibility.
Your health care agent cannot also serve as a witness to the document. In many states, the following people are also disqualified from witnessing: relatives, anyone who stands to inherit from your estate (whether through a will or by default under state law), your health care providers, and anyone with a financial claim against your estate. Texas, for instance, requires that at least one witness have no financial connection to your estate whatsoever.
Some states allow you to use a notary public instead of witnesses. Kentucky, for example, permits notarization as an alternative. Check your state’s specific requirements, as the rules on witnessing vary more than the rules on who can be an agent.
What Makes Someone a Good Choice
Legal eligibility is the minimum bar. The more important question is whether the person will actually do the job well. A few qualities to prioritize: the person should live close enough (or be reachable enough) to show up at a hospital on short notice. They should be comfortable asking doctors pointed questions and pushing back if they feel your wishes aren’t being respected. They need emotional steadiness, because these decisions often involve end-of-life care, pain management, ventilators, and feeding tubes.
Most importantly, your agent needs to know what you want. That means having direct, specific conversations before anything happens. Tell them how you feel about resuscitation, mechanical ventilation, artificial nutrition, and comfort-focused care. Write those preferences in a living will or advance directive so your agent has a reference point, not just a memory of a single conversation. The legal authority to act on your behalf only works if the person holding it knows what you would choose.