For 2018 coverage and beyond, there is a 45-day window for enrollees to return to the marketplace and renew their coverage. In most states, open enrollment for 2018 coverage is from November 1, 2017 to December 15, 2017. You must return to the marketplace to update your eligibility and enroll into a health plan by December 15, 2017. Some states may have a longer open enrollment so check with your state marketplace. (45 C.F.R. § 147.104; 82 Fed. Reg. 18346, April 18, 2017).