November 1, 2016: Open Enrollment started — first day to enroll, re-enroll, or change a 2017 insurance plan through the Health Insurance Marketplace.
December 15, 2016: Last day to enroll in or change plans for coverage to start January 1, 2017.
January 1, 2017: 2017 coverage started for those who enrolled or changed plans by December 15.
January 31, 2017: Last day to enroll in or change a 2017 health plan. After this date, you can enroll or change plans only if you qualify for a Special Enrollment Period.