There is still time to enroll in or change 2018 Marketplace health insurance. The 2018 Open Enrollment Period runs until December 15, 2017. It's important to act quickly. If you don't act by December 15, you can't get 2018 coverage unless you qualify for a Special Enrollment Period. Go online to healthcare.gov or call 1-800-318-2596 where someone is available to help 24 hours a day.