July 16, 2021 18:22 Updated Follow There are several things that factor into the final cost of extra service. We suggest you read Buying Extra Service Credit if you are a member of PERF or TRF. For other funds, . Related articles Do you accept credit cards? I was a substitute teacher. How can I add this service to my account? How many years of creditable service must I have in order for my spouse or child to receive a survivor benefit from PERF? Are credit cards and prepaid debit cards for gas given out to participants in court programs allowed? What is needed for payment of credit card charges?