Is there any limit to the number of IRA to Roth IRA conversions that an individual can make in one tax year?

The only limits I am aware of are the MFS and $100,000 MAGI.

The main rules apply to the qualification to convert. Qualification is determined for the complete tax year and if you income is borderline you will know for sure when you crunch the numbers and prepare your return.

You can clearly do more than one conversion in a year ... but after a while your custodian might start getting annoyed. The paperwork burden is mostly on their side, you just need to hand them a letter of instructions.

There are other limitations if you try to reverse the process and undue a conversion. But that does not appear to be your question.

Thanks, James and John.