Reporting a backdoor Roth conversion isn’t always easy on your taxes. Turbotax requires a 2 part solution where you enter it as a 1099-R conversion, then characterize it in your income section as a conversion within 60 days.

As of Jan 2025, the form has *already* changed again; but this is the closest set of dialogs that matches what you need to do:

https://ttlc.intuit.com/turbotax-support/en-us/help-article/retirement-benefits/enter-backdoor-roth-ira-conversion/L7gGPjKVY_US_en_US