You may have heard about Open Season or Open Enrollment for your Tricare or Federal Employees Dental and Vision Insurance Program (FEDVIP) coverage. But what exactly is it? Open season (also known as open enrollment) is the time each year when you can make changes to your Tricare and FEDVIP dental and vision coverage for the following year. Federal employees can also make changes to their health insurance during this time period. Read more on Military.com.