The period of time during which individuals who are eligible to enroll in a Qualified Health Plan can enroll in a plan in the Marketplace. For coverage starting in 2015, the Open Enrollment Period is November 15, 2014–February 15, 2015. Individuals may also qualify for Special Enrollment Periods outside of Open Enrollment if they experience certain events. (See Special Enrollment Period and Qualifying Life Event)
You can apply for Medicaid or CHIP, at any time of the year.