This answer is from I have been researching IBR for student loans, I am married and we both have loans
Mark Kantrowitz said
Yours and his loans are treated separately. If you file your income tax returns as married filing joint your income is combined for IBR. If you file as married filing separate, only your own income will be considered for your loans.
If you will be pursuing public service loan forgiveness, it would be advantageous for you to file as married filing separate so that only your income is considered when calculating the monthly payment on your loans.


