Even though the result seems unreasonable, this is actually not an error by TurboTax. The IRS instructions for Form 8949 say that if rounding is done, all amounts entered must be rounded. TurboTax is following this instruction precisely and the consequence is that you end up with a $1 gain. The same would be true if you prepared Form 8949 yourself and used rounding in the way that the IRS instructs. The only way to end up with $0 of gain or loss in this case while simultaneously following the IRS instructions would be to carry the cents everywhere on the form. TurboTax does not provide an option to carry the cents on this form.
