IRA RMD apportion between two states

[Twostates]

If IRA RMD is taken in December is the entire amount apportioned to the state one lives in on December 31st

[MaryK4]

Yes, retirement income (including RMDs) are taxable by the resident state when you received the income, so in your case you can allocate it all to the state where you lived in December.

[neilsklarew]

can I choose to apportion an IRA RMD to either of the other state I lived in during the year, and not to the one I lived in on December 31st?

[JohnB5677]

No, that would be incorrect.  The retirement withdrawal should be allocated to the state you were living in at the time of payment.