More answers: Are you eligible to use the Marketplace?
If you’re considered a “resident” of the United States for tax purposes, you’re eligible to use the Marketplace.
Generally, health insurance in the Marketplace covers health care provided by doctors, hospitals, and other providers within the United States. If you're living abroad, it's important to know this before you consider buying Marketplace insurance.
A U.S. national is someone who’s a U.S. citizen or a person who isn’t a U.S. citizen but owes permanent allegiance to the U.S.
With extremely limited exception by which he or she is entitled to be protected, all non-citizen U.S. nationals are people born in American Samoa or abroad with one or more American Samoan parents under certain conditions.
U.S. territories can decide whether to create their own Health Insurance Marketplace® or expand Medicaid coverage. Residents of a U.S. territory aren't eligible to apply for health coverage using the federal or state Marketplace unless they also qualify as a resident within the service area of a Marketplace.