A nonzero amount in box 2a of a code G Form 1099-R implies to the IRS that the rollover was to a designated Roth account in the plan or to a Roth IRA and represents taxable income that should appear in your AGI. If you indicate to TurboTax that the rollover was not to any type of Roth account, causing TurboTax to treat the rollover as nontaxable, anticipate the IRS to send a letter indicating unreported taxable income and a balance due. If the rollover was to a traditional IRA or to a traditional account in qualified retirement plan, I suggest contacting the payer to obtain a corrected Form 1099-R. If they refuse I would submit a substitute Form 1099-R (Form 4852) with a zero in box 2a and an explanation as to why the rollover is not taxable, although this will prevent e-filing, I believe.
