Less than a third of investors are aware of a closing loophole that could allow them to convert a Roth IRA into a traditional IRA.

According to a survey conducted by Fidelity Investments that was released Thursday, 30% of investors who are eligible to complete a Roth IRA conversion are aware that they can “undo” that move.

The process, which is known as “recharacterization,” allows an investor to reverse amounts converted from a Traditional IRA to a Roth IRA and recover any taxes paid. But, this conversion must be completed by Oct. 15.

The telephone survey of 1,0008 adults, wich was conducted in July, also indicated that when investors were asked what circumstances would spur them to convert their Roth IRA, the top reason (54%) cited was an unexpected drop in their taxable income in retirement. Forty-four percent of investors said they would convert if the additional taxable income from a Roth IRA conversion puts them into a higher federal income tax bracket.

Other reasons included not having sufficient cash reserves to cover the tax bill (35%) and a significant drop in the value of investments after converting to a Roth IRA (32%).

“Deciding whether to convert to a Roth IRA or not, as well as the resulting tax implications from the conversion, can be confusing for many investors,“ said Chris McDermott, a senior vice president of investor education, retirement and financial planning at Fidelity. “Knowing that they have the ability to reverse the Roth IRA conversion in the event their financial situation changes can help them be more confident in making a decision.”

According to Fidelity, all or a portion of the amount an investor converted can be recharacterized, and traditional IRA balances can be reconverted back to a Roth IRA in the next tax year or 30 days after the recharacterization, whichever is later.

“The removal of income restrictions on Roth IRA conversions this year opened the door for many investors to have access to this type of account for the first time,” McDermott said. “We encourage investors to do their homework, work with their tax professionals, and fully understand how a Roth IRA might fit into their long-term retirement plans and potentially help minimize taxes and maximize retirement savings.”