It depends. To reverse a conversion by recharacterizing an account back to traditional IRA status you must submit the required form to your Roth IRA trustee or custodian by October 15 of the year after the conversion takes place. If October 15 falls on a weekend, the deadline is the following Monday. This flexibility makes the conversion idea that much more appealing.
If you’ve already filed your tax return for the year of the conversion but it isn’t yet October 15, you still have until that date to reverse the conversion (with extra days in years when October 15 falls on a weekend). To get back the tax you paid on the conversion you would then need to file an amended tax return (using Form 1040X) by the due date for amended returns. (Usually you have three years after the date you filed the original return, but you shouldn’t wait that long to seek a refund from reversing a Roth conversion.)
can reverse a Roth IRA conversion.
Here is a TurboTax article with more information.
