You do not have to be a US citizen to purchase health insurance, but you do have to be a documented (lawful) permanent resident or green card holder. If you do not have legal status in the US, there are still some options available to you (see #2 below).
1. If you are documented, or fall into any of the following categories below, you can get traditional coverage, and take advantage of discounted (subsidized) plans:
- Lawful Permanent Residents (LPR/Green Card Holders)
- Individuals with non-immigrant status (worker visas, student visas, and citizens of Micronesia, the Marshall Islands, and Palau)
- Victims of Trafficking
- Lawful Temporary Resident
People with the following statuses and who have employment authorization qualify for the Marketplace:
- Registry Applicants
- Order of Supervision
- Applicant for Cancellation of Removal or Suspension of Deportation
- Applicant for Legalization under Immigration Reform and Control Act (IRCA)
- Legalization under the LIFE Act
(You can see a more detailed list with descriptions of these statuses here.)
2. If you are not documented and do not fall into any of these categories, you are not eligible for coverage through healthcare.gov or any State or Federal marketplaces. You can, however try a private insurer for short term medical and accident insurance here.
If you go uninsured, there are a couple of other options for health care. You are eligible for emergency care under Federal law. You may also seek non-emergency health services at community health centers, which do not ask about immigration status. You can find your nearest health center here.