The Arizona State Retirement System (ASRS) pays pension benefits to the state’s public school teachers, but the system is substantially underfunded. This report uses an actuarial model to estimate how much taxpayer contributions to ASRS will likely have to increase to close the system’s financing gap under current benefit rules and various investment return scenarios. Our results show that annual employer contributions to ASRS may have to more than double in coming years to make the system solvent under the current benefit structure. In addition, teachers who spend less than a full career in the system receive only limited pension benefits.