RMD for 9/30 FYE Plan

For a September 30 FYE plan, when calculating the RMD can/do you use the 9/30 balance or do you need to determine the 12/31 balance and calculate the distribution based on that year end balance? 

Thanks

Is this a pooled plan, or individual accounts?

Pooled... which is why I am asking and which is why I have in the past just used the 9/30 year end balance.  If they were segregated brokerage accounts using 12/31 would have been easy.  

If the plan has only yearly valuations each September 30, isn't a December 31 balance the same as the preceding September 30 balance?

Unless the plan has quarterly valuations, I would go with the 9/30 balance.

The rule is that you use the balance on the last valuation date in the calendar year immediately preceding the distribution calendar year, with adjustments.

For the 2021 distribution calendar year, you would use the account balance as of the 9/30/2020 valuation date. Increase it by the amount of any contributions allocated to the participant's account, or decrease it by the amount of any distributions made from the participant's account between 10/1/2020 and 12/31/2020.

As C.B. says, this gets you a "pseudo 12/31/2020" account balance that the regulations allow.

Ahh... yes.  Thank you C.B., that is what I was looking for. 

RMDs are part of the basic operation of a plan... something that must be done.   I sometimes second guess my knowledge.

Appreciate the help.