Heck...call the provider of that 1099-R and ask.
I have two 1099-Rs issued from Fidelity...one for a Pension from one company, and one from a 401k from a different company...both handled by Fidelity. There is nothing on the 1099-R forms that indicates which is a 401k...but the original company it represents is at the bottom of the "Payers" address.
But then, I already know which is the 401k and which is the Pension, because my Pension pays the exact same amount every year....and the 401k varies considerably.
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
