Foster Youth Independence Act of 2017 This bill amends part E (Foster Care and Adoption Assistance) of title IV of the Social Security Act to allow the chief executive officer of a state to certify that the state will provide assistance and services under the John H. Chafee Foster Care Independence Program to youths who have aged out of foster care and have not attained age 23 if: the state has elected to extend the eligibility for foster care up to age 21, or the responsible state agency uses state or other funds not provided under the program to provide assistance and services comparable to those such youths would receive if the state had made such an election.