In general, you can only enroll in non-group health plan coverage during the Open Enrollment period.
This year the Open Enrollment period begins October 1, 2013 and extends through March 31, 2014. After that, the Marketplace Open Enrollment period will be shorter, lasting from October 15 through December 7. Once the Open Enrollment period is over, individuals and families will not be able to enroll in Marketplace health plans until the next Open Enrollment period. However, if you experience certain changes in circumstances during the year, you will have a special 60-day opportunity to enroll in Marketplace health plans, outside of the Open Enrollment period.
For individuals and families buying non-group coverage on their own, outside of the Marketplace, you can only enroll in coverage during Open Enrollment periods and special enrollment opportunities, as well.
American Indians and Alaska Natives can enroll in coverage throughout the year, not just during Open Enrollment.