the info on the 1099R instructions says as much
Box 2a. This part of the distribution is generally taxable. If there is no entry in this box, the payer may
not have all the facts needed to figure the taxable amount. In that case, the first box in box 2b should
be checked. You may want to get one of the free publications from the IRS to help you figure the
taxable amount. See Additional information. For an IRA distribution, see IRAs and Roth IRAs above.
For a direct rollover, other than from a qualified plan, sec. 403(b) plan, or governmental sec. 457(b)
plan to a designated Roth account in the same plan or to a Roth IRA, zero should be shown, and you
must enter zero (-0-) on the "Taxable amount" line of your tax return. If you roll over a distribution
(other than a distribution from a designated Roth account) from a qualified plan, section 403(b) plan,
or governmental section 457(b) plan to a Roth IRA, you must include on the "Taxable amount" line of
your tax return the amount shown in this box plus the amount in box 6, if any.
Box 2b. If the first box is checked, the payer was unable to determine the taxable amount, and box 2a
should be blank, except for an IRA. It is your responsibility to determine the taxable amount. If the
second box is checked, the distribution was a total distribution that closed out your account.
