In general, the law allows children to be covered by Federal Employees Health Benefits program up to age 26, even if they are married but at that point, their FEHB coverage ends. However, coverage can be continued if the child is unmarried and is incapable of self-support due to a disabling condition in existence before that age.
Acceptable evidence includes certification by a state or federal rehabilitation agency that the child is unemployable, receipt of survivor benefits from CSRS or FERS as a disabled child, receipt of benefits from Social Security or OWCP as a disabled child, or a medical certificate documenting that the child is incapable of self-support
If you are an employee, you’ll have to provide that evidence to your personnel office, which will determine if the criteria are met. If they are, it will notify your FEHB plan. If you are retired, you’ll have to notify OPM, which will make the determination and provide it to your plan. Depending on the nature of your child’s disability, it may be necessary to periodically reconfirm that the disabling condition still exists.
The coverage will end if the child marries, recovers from the disability or becomes capable of self-support. They usually can be restored if the marriage ends, the original disability returns or the child is no longer capable of self-support.
Note: The term “incapable of self support” generally means that the child earns less than the equivalent of GS-5, step 1. However, this is not a hard and fast rule. In making a decision, consideration is given to the child’s earnings and condition or prognosis.