Originally Posted by jazz4cash
Is that accurate? I thought you paid the tax up front at the time of the conversion.
You pay tax on any gains, but it is called an in plan conversion and you pretty much pay no tax (note the money goes into the 401k after tax so there was tax paid at some point).
Essentially it is like this:
Normal folks: $17,500 into 401K, $5500 into Roth
Lucky folks: $17,500 into 401K, $20,000 or more into 401K after tax -> immediately converted to Roth, $5500 into Roth.