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I cant imagine her student loan payments will dramatically increase.
You will save money on income tax.
Even if you have to pay $100-$200 more on student loans, you will be better off married since you have to pay the loans anyway and they will be accumulating compound interest on the balances.
Again, I doubt they will dramatically increase based on your current income level assuming she does not make dramatically less than you.
You can find SL calculators online to get a guestimate.
Happy wife, happy life.
GL.
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My boss and his wife file separately because of student loan repayments - but he makes a whole lot more than your combined incomes (and his wife's is far less), so it's a pretty significant impact for them - they've worked out the math (I think it's nuts for the reasons Shooting-for-800 says - neither are on PSLF/Repaye, so they'll just end up paying more in the long run).
You can speak with a tax/financial advisor to see how the math works out, or you can do the math yourself - there are repayment calculators on the Dept of Ed website that can calculate the differences for you, and also use the IRS tax calculator for 2019 to figure it out.
Good luck.