You may be wondering what action you need to take, if any, to ensure you continue TRICARE coverage in 2018. If you’re currently enrolled in or eligible for TRICARE coverage on Dec. 31, 2017, you’ll transition to your respective TRICARE plan on Jan. 1, 2018. If you want to enroll in a TRICARE plan or change coverage after Jan. 1, 2018, you’ll need to take action to enroll in the plan of your choice.