You can use the government’s online calculator to compute the tax-free portion of your annuity. It is at the following link: http://apps.opm.gov/tax_calc/index.cfm. Here you can read about how the tax-free portion of your federal retirement annuity is determined. Your retirement contributions are shown on the 1099R form the government sends you each January for tax filing purposes. You can find information about computing the taxable portion of your annuity by going to IRS Publication 721 (Tax Guide to U.S. Civil Service Retirement Benefits) on the Internal Revenue Service website. Search for Publication 721 and refer to “Part II Rules for Retirees”. You will find detailed information for disability and non-disability retirees, along with worksheets for computing the taxable portion. If your non-disability annuity started on or after July 2, 1986, a portion of each annuity payment is taxable and a portion is considered a tax-free recovery of your contributions to the retirement fund. If you retired under the disability provision, the disability annuity you receive from CSRS or FERS is taxable as wages until you reach your minimum retirement age. Your retirement contributions are shown on the 1099R form the government sends you each January for tax filing purposes.