I'm doing a tax return for someone who died in 2020. Her CSA-1099-R has "unknown" in box 2a (Taxable Amount). How do I determine the taxable amount?

[chris-s-madden]

By the time she passed away she had used 256 of the 260 months credit from Worksheet A. Simplified Method. Can I reduce the taxable amount by the 4 months she still had to go?

[chris-s-madden]

IRS publication 721, part II Rules for Retirees, states, 

"Deduction of unrecovered cost.

If your annuity starting date is after July 1, 1986, and the cost of your annuity hasn't been fully recovered at your (or the survivor annuitant's) death, a deduction is allowed for the unrecovered cost. The deduction is claimed on your (or your survivor's) final tax return as an "Other Itemized Deduction." If your annuity starting date is before July 2, 1986, no tax benefit is allowed for any unrecovered cost at death."