Thank you for your response. I also couldn't find the amount from box 5 anywhere else in the (previous year) tax return. I thought that perhaps it could have affected the non-taxable amount of the annuity, but that doesn't seem to be the case. Do you know where the difference between the gross distribution in box 1 and and taxable amount in box 2a come from? I suspect that it may somehow be related to the Total Employee Contribution in box 9b.
