special enrollment period
DEFINITION: A special enrollment period is the time during which you can enroll in an ACA-compliant plan (on or off-exchange) if you have a qualifying life event. In most cases, the special enrollment period lasts for 60 days following the qualifying event.
Read more about special enrollment periods.
In the case of loss of employer coverage (and possibly individual coverage, pending a new HHS regulation), the special enrollment period begins in advance of the loss of coverage so that enrollees can purchase a new plan with no gap in coverage.
If you do not have a qualifying event that triggers a special enrollment period, you can only enroll in an ACA-compliant plan (on or off-exchange) during the regular annual open enrollment period.