GBP-eligible dependents—those who can receive GBP health coverage—include eligible state and higher education employees' and retirees' spouses, children up to and including age 25 in several categories, and disabled children age 26 and older. See the Dependent Eligibility Chart
for more information. GBP-eligible dependents are allowed to participate in GBP health coverage, but are not required to.
For the purposes of health coverage, the ACA considers a dependent to be a child or other individual that an adult or married couple may claim as a dependent for federal income tax purposes. In these questions and answers, we refer to dependents in this context as "federal tax dependents."