US health care is very expensive. One night in a hospital can cost thousands of dollars, and visitors on a B visa or ESTA pay the full price. Buy visitor insurance before the trip.
Visitors cannot use US public plans
Visitors cannot join Medicare or Medicaid, or buy a plan on healthcare.gov.
A family member's work insurance does not cover visiting parents.
Hospital emergency rooms must examine and stabilize anyone, but they send a bill later.
Buy a visitor or travel medical plan that starts on the day of arrival and covers the whole stay on the I-94. Many can be bought online from abroad or from the US. Insurance bought after someone is already sick will not cover that illness.
Maximum benefit: the most the plan pays. US hospital stays cost a lot, so a low limit runs out quickly. Older travelers often pick a higher amount.
Deductible and coinsurance: what the visitor pays first, and their share after that.
Network: doctors and hospitals that bill the insurer directly. Outside it, you may pay first and claim later.
Age: prices rise sharply with age, and some plans limit benefits after 70 or 80.
Medical evacuation and repatriation: transport home if needed.
Exclusions: read the list of what is not covered.
What is usually not covered
Pre-existing conditions: problems the person already had, such as diabetes, heart disease or high blood pressure. Many plans pay nothing for them.
Some plans cover only a sudden, unexpected flare-up of an old condition (acute onset), often with a low limit. Read the exact words.
Routine check-ups, regular medicines, dental and eye care (some plans add small emergency amounts).
Ask their doctor at home for a written summary of conditions, medicines and allergies, in English if possible.
Bring enough regular medicine for the whole visit, in original packages. See Customs: food, cash, medicines and gifts.
Save the insurance card and claims phone number on your phone and theirs. Print a copy too.
Find an in-network urgent care clinic and a hospital near your home.
For minor problems, call the insurer first and ask for an in-network urgent care. It costs far less than an emergency room.
For a real emergency, call 911 or go to the ER first; call the insurer after.
Show the insurance card at check-in. Keep every bill, receipt and report.
Ask the hospital for an itemized bill and its financial assistance policy. Nonprofit hospitals must have one; ask whether visitors can apply.
File the claim quickly. Plans have deadlines.
Parents with a green card
Parents who become green card holders do not get Medicare right away. Many can buy Medicare after 5 years of living in the US as permanent residents. Plan private insurance for the first years.
Buying the cheapest plan with a very low limit, without reading the pre-existing condition rules.
Assuming a home-country travel card covers US prices fully.