October 15 is the deadline for undoing a 2009 Roth conversion. You’d want to take this action if you’ve learned your conversion didn’t qualify, perhaps because your income was too high that year. (The income limitation was eliminated as of 2010.) You might consider it if your tax situation changed to make it unwise, or if your financial situation makes it difficult for you to do without the tax dollars you had to pay on the conversion.
The most frequent reason for undoing a Roth conversion, though, is a loss of value in the account after the conversion. Relatively few people are in that situation just now: the stock market is higher now than it was at nearly any point in 2009 — and roughly 70% higher than it was at the low point in March of that year. If you made some unfortunate investment choices that leave you with a diminished balance since the date of your conversion you have less than two weeks to evaluate your choices and take action if needed. Most people who converted last year will be able to stick with a decision that worked out well.
