TurboTax Online/Mobile: Go to 1099-R or go to magnifying glass at top right of screen and and Search for and select 1099-R.
Enter the details from your 1099-R form. TurboTax will ask for information such as the payer's details, the gross distribution, and the taxable amount.
Continue through the question and TurboTax will guide you.
I guess it depends on what page you are looking at....
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1) IF you are on the initial form selection page...then it's just a standard 1099-R. (i.e. it is NOT a CSA-, CSF- nor RRB-1099-R)
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2) If you've already entered your 1099-R data, and are looking at a follow-up page that asks where the Distribution is from,...then that answer depends on what state you are filing for...because the selections presented are differed for every state with an income tax...(Thus, we can't know what choices you are being given unless you list them)
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*