During the annual FEHB Open Season, anyone eligible to participate in the FEHB Program may enroll, change health plans or options, cancel your FEHB enrollment, and change participation in premium conversion (waive or begin participation).
Outside of Open Season, newly eligible employees may enroll within 60 days of their becoming eligible for the program, members who move outside of the area covered by their plan may enroll in a different plan covering their new location, and OPM may announce special Open Seasons affecting members of specific plans only. There are also a number of other circumstances which can make you eligible to enroll or change your FEHB coverage outside of Open Season.
Instructions for Making an Open Season Enrollment Change