Can I max out 401k and also contribute to an IRA in order to convert to Roth?

Hello there. My wife and I file jointly, our household income is above the IRA deduction limits and also above the Roth IRA limits. We both maxed out our 401k, but I recently heard that we could still contribute up to $6000 (each) to an IRA and then roll it over to each of our Roth IRA. Is this doable? It sounds like a silly and to-good-to-be-true loophole, but I was made aware of this by a representative of my 401k broker; they are not tax experts though.

 

In summary, can a married filing jointly couple earning more than the phase out limits, max out a 401k and also contribute $6000 to an IRA with the goal of rolling those $6000 into a Roth IRA?

 

Thank you in advance.