When entering the code H Form 1099-R for the rollover from the Roth 401(k), box 5 should have shown your contribution basis which TurboTax would have automatically added to your Roth IRA contribution basis. If the payer failed to show the basis in box 5, click the Continue button on the page that lists the Forms 1099-R that you have entered and entered and add the amount yourself when TurboTax offers the opportunity to check or edit your Roth IRA contribution basis.
If the code on the Form 1099-R includes code B, you must indicate that the money was moved to another retirement account, that it was rolled over and that it was rolled over to a Roth IRA. TurboTax will again treat the box-5 amount as Roth IRA contribution basis.
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