Telehealth Improvement for Kids' Essential Services Act or the TIKES Act This bill requires several agencies to promote and evaluate the use of telehealth under Medicaid and the Children's Health Insurance Program (CHIP). Specifically, the bill requires (1) the Centers for Medicare & Medicaid Services to issue guidance to states on ways to increase access to telehealth; (2) the Medicaid and CHIP Payment and Access Commission to study the impact of telehealth on health care access, utilization, costs, and outcomes; and (3) the Government Accountability Office to evaluate federal interagency collaboration with respect to the provision of telehealth services to individuals under the age of 18.