When entering the code-G Form 1099-R reporting a rollover to a Roth account, TurboTax asks if the rollover was to a designated Roth account in the same 401(k) plan (an In-plan Roth Rollover) and then, if the answer to the first question is No, TurboTax asks if the rollover was instead to a Roth IRA. Answering these questions incorrectly will result in an incorrectly calculated MAGI for the purpose of a (separate) Roth IRA contribution.
The MAGI for the purpose of a Roth IRA contribution is reduced by the amount of a taxable rollover from the traditional account in a 401(k) to a Roth IRA, but is not reduced by the amount of an In-plan Roth Rollover.
