@dmertz wrote:
Since the original question as about a mega backdoor Roth and just the after-tax subaccount was in-plan rolled over to the designated Roth account, it appears that the taxable amount of the In-plan Roth Rollover is $0.
OK, assuming that "401K AT" means "after-tax 401(k)", I guess I don't know the difference between an "after tax" 401(k) and a designated Roth 401(k) account. If the money was always after tax, it would not be taxed now.
