Federal Retirement Fairness Act This bill modifies the federal civilian service that is creditable service under the Federal Employees Retirement System (FERS). Specifically, it expands the nondeduction service that may be creditable under FERS. Nondeduction service is federal service where an employee's pay is not subject to retirement deductions (e.g., service under a temporary appointment). Currently, nondeduction service performed before January 1, 1989, is creditable under FERS so long as a deposit is made into the retirement fund to cover the period of nondeduction service. This bill allows nondeduction service performed on or after January 1, 1989, to be creditable under FERS so long as a deposit is made into the retirement fund.