Deductions & credits

I'm not a good source for that situation...I do see some references that if you are filing MFS, the amount you can deduct may be halved too in certain situations.  I have no idea if TTX applies the limit properly or not.

 

There's a bunch of details in the 2019 Pub 936  (didn't find a 2020 version).

 

https://www.irs.gov/pub/irs-pdf/p936.pdf

 

____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*