Why does TurboTax ask what portion of each IRA Distribution goes to my RMD?

[jayw2001]

While filling out my 1099-R forms, for each of my 1099-R IRA distributions, TurboTax asks me "how much of this IRA Distribution goes towards my RMD?" WHY does TurboTax need to know this? Doesn't the IRS only need to know that my TOTAL IRA distributions from all of my IRA accounts in any given year is at least equal to or greater than my RMD amount for that year?

[JosephS1]

TurboTax asks about the RMD simply as a precautionary question.  Many taxpayers are unaware of the RMD requirements and end up paying the 50% excise tax.  You probably are seeing the following screen as you go through the questions:

In addition to the above screen, if there was only a partial RMD or no RMD from that particular distribution the following screen will also appear as you go through the questions.  These questions, please remember, are only cautionary and to assist all in avoiding unnecessary penalties.

@jayw2001

[Opus 17]

There are certain things you can do with your income that you can't do with the RMD portion of a retirement withdrawal.   For example, you can't rollover your RMD to a Roth IRA.  If you withdrew $6000 and your RMD was $5000, you have the option of converting up to $1000 to a Roth IRA but not more.  I can't remember the full list of thing you can't do, but if you really want to know, I think some of the other regulars know.

@dmertz 

@Hal_Al 

In any case, Turbotax asks for the amount of your RMD so it knows that a certain portion of your income is not eligible to be used for these prohibited purposes.  It enters the figure on its internal worksheets, so the information will be available later if you indicate you did one of those things that is limited by the RMD rules. 

[dmertz]

The ONLY reason that TurboTax asks the question during entry of a Form 1099-R is to help determine how much of the distribution is eligible for rollover.  Substitute "ineligible for rollover" for "RMD" in this question being posed by TurboTax and it will make more sense.

Of course there are some distributions that are not eligible for rollover even if they are not RMDs, so the question as asked really doesn't do a good job of accomplishing what it is intended to do.