"All they need is a field for total RMD required, then compare the sum of the amounts withdrawn against that figure to determine shortages and/or penalties."
It's nowhere near that simple. While RMDs for traditional IRAs are permitted to be combined and RMDs for 403(b)s are permitted to be combined, RMDs for IRAs and 403(b)s are not permitted to be combined with each other. Also, RMDs for inherited accounts are not permitted to be combined with RMDs for owned accounts, although RMDs for accounts inherited from the same beneficiary and subject to the same RMD calculation can be combined. RMDs for other types of retirement accounts are not permitted to be combined. As a result, TurboTax developers put on the user the responsibility for determining what RMDs can be combined RMDs.
