Questions about entering inherited IRA information

[mdcbk]

I inherited 50% of an IRA from my mother who passed in 2025. My brother and I each took the entire amount of our shares in a lump sum distribution. Two questions:

1. Box 9a displays 50%. Turbotax states "Box 9a is only used if the box 1 amount on this Form 1099-R was split between two or more people." My 1099-R box 1 only reflects what I received, not the original amount that was split between the two of us. Am I interpreting Turbotax incorrectly? Is my 1099-R incorrect?

2. How do I answer the RMD interview question: "we need to know the amount that was required to be distributed by December 31, 2025?" I don't have th  at info. I could estimate the amount using an online calculator, or I could just enter the full amount that I received. I know the question is just to evaluate if I'm subject to any penalty, but I'm not sure what to put there. 

Thanks.

[DavidD66 · Accepted solution]

Box 9a does not have any impact on the taxable amount of your IRA distribution.  If the amount in Box 1 was not the actual amount you received and instead was 100% of the Inherited IRA the percentage in this box would be used to calculate your taxable amount.  Your 1099-R is correct. 

You are correct, the question is just to determine whether or not a penalty should be calculated.  It doesn't matter what you enter.  The total amount of the distribution would be fine, as would $0 (which is the correct amount if your mother had not yet reached the age requiring RMDs).