Thank you for the reply.
The 'internal' 1099-R (which is on the website but was not mailed to my son) has code H.
The version mailed to my son has code J.
So, you are suggesting we provide a value for box 2a (for the lesser amount we know is taxable) even though the form was provided with this field blank and with box 2b "Taxable amount not determined" was checked?
If so, do we then 'uncheck' this box for the input in TurboTax?
Do we also need to enter the details for the 'internal' version of the 1099-R which wasn't actually provided to him?
Thank you.
