[arcastroe]

Wait. I refinanced a mortgage and naively filed my taxes with TurboTax this year. What's the bug?

[Rebelgecko]

I actually haven't seen anyone complaining about the bug, so maybe it's been fixed after multiple years?

There's a good rundown of the bug here: https://www.reddit.com/r/personalfinance/comments/lqkcdv/how...

tl;dr is that the mortgage interest deduction is prorated if your mortgage(s) have a total principal > 750k. If you refinanced, TurboTax would do the proration calculation assuming your mortgage were twice as large, because the refinance was being treated as a separate mortgage