When a tribal employer chooses to participate in the Federal Employees Health Benefits (FEHB) Program, the Initial Enrollment Opportunity occurs. It is the time period for eligible tribal employees to enroll in the FEHB Program. Please check with your tribal employer to see if they have elected to participate in FEHB and if they have, when your Initial Enrollment Opportunity occurs.
During the annual FEHB Open Season, which is held mid-November through mid-December, anyone eligible to participate in the FEHB Program may enroll, change health plans or options, cancel FEHB enrollment, and change participation in premium conversion (waive or begin participation). If the tribe, tribal organization or urban Indian organization participates in premium conversion, employees may change their premium conversion status.
Outside of Open Season, newly eligible employees may enroll within 60 days of their becoming eligible for the FEHB program, members who move outside of the area covered by their HMO may enroll in a different FEHB plan covering their new location. OPM may announce special enrollment opportunities affecting members of specific plans only. There are also a number of other circumstances (qualifying life events) which can make you eligible to enroll or change your FEHB coverage outside of Open Season.
Instructions for Making an Open Season Enrollment Change
To Make Any of These Changes
Employees:
You can submit Standard Form 2809, Employee Health Benefits Election Form 
[849 KB], to your Human Resources Office: