"Some say if box 7 has the number 7 it’s tax free if you met the plans retirement age"
@Terry0803 , it's almost certain that some, if not most, of a distribution from FERS or CSRS is taxable, regardless of your age. Distributions almost certainly consist only partly of a portion of your after-tax investment in the plan, with the remainder of the distribution being taxable. It would be extremely unusual, if not impossible, that the distribution was entirely tax free. If you made no after-tax investment in the plan, the entire distribution is taxable.
If you made after-tax investments in the plan, the taxable amount is required to be determined using the Simplified Method, which TurboTax will give you an opportunity to choose. The Simplified Method takes into account your Plan Cost (after-tax investment in the plan) to calculate the portion that is tax free. Once you have received a sufficient number of distributions to have distributed all of your after-tax investment in the plan, subsequent distributions will be entirely taxable.
If the plan knew this amount, they would have simply put the actual taxable amount in box 2a. Since they have effectively lost the records of your investment in the plan, they are putting the responsibility on you determine the amount of your after-tax investment in the plan and provide that when using the Simplified Method to calculate the taxable and nontaxable amounts.
