Q. I will be retiring from civil service under CSRS with 40 years of service. I will also be drawing my reserve retirement next year when I turn 60. I have three years and nine months of unpaid military service, and it would cost approximately $26,000 to buy back the service. I know when I turn 62, the Social Security windfall elimination provision will reduce my Social Security annuity. I have less than 20 years of significant earnings. I’m wondering if it is worth paying the $26,000 to buy back the three years and nine months.