During Open Enrollment, you can shop for a different plan. You should sign up for new coverage during Open Enrollment in order to remain insured next year and receive the most accurate premium tax credit possible. If you don’t act by the end of Open Enrollment and you live in a HealthCare.gov state, the Marketplace will automatically enroll you in a new plan. The Marketplace will try to pick the lowest cost plan that is as similar as possible to the one you have now.