From this website: https://www.healthinsurance.org/faqs/what-are-the-deadlines-for-obamacares-open-enrollment-period/ by Louise Norris

In most states, open enrollment for 2021 health plans ended on December 15, 2020. HealthCare.gov, which is the exchange platform that’s used by the majority of the states, tends to follow this schedule fairly closely, while the states that run their own exchange platforms generally offer slightly longer enrollment windows.

But the Biden administration has announced a COVID-related special enrollment period on HealthCare.gov. It will run from February 15, 2021 through May 15, 2021, and will be available for anyone who is eligible to use the marketplace, including people who are currently uninsured as well as those who already have coverage through HealthCare.gov and would prefer to pick a different plan.

HealthCare.gov is used in 36 states for enrollment in 2021 health plans, and the special enrollment period will be available in all of them. In addition, many of the state-run exchanges are offering similar COVID-related special enrollment periods in 2021:

• California: February 1 to May 15
• Colorado: February 8 to May 15
• DC: Through the end of the pandemic emergency period
• Maryland: Through March 15
• Massachusetts: Through March 23
• New Jersey: Through May 15
• New York: Through March 31
• Washington: February 15 to May 15

Other state-run exchanges, including Minnesota’s, are expected to announce similar special enrollment periods in the coming days.

Outside of open enrollment, plan changes and new enrollments are normally only possible for people who experience a qualifying event, but the COVID-related special enrollment periods in most of the country are providing significant flexibility on this for 2021 coverage.

Native Americans and Alaska Natives can enroll year-round in plans offered in the exchange. Applicants who are eligible for Medicaid or CHIP can also enroll year-round. This is true every year, not just in 2021.

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