FNMA = 25%

FHA = the higher of 15% or the appropriate tax rate based on their income & filing status
VA = the appropriate tax rate based on their income & filing status
USDA = 25%
In all cases you must evidence portion of the SSI that is not taxed based on the most recent years filed tax returns. Below is a snip of the 2017 tax brackets

Original question:

I was wondering the percentages for grossing up Social Security Income when it is not taxed. I am not sure when it is 15% and when it is 25%.

I have looked it up but could not find anything on it in the search.

I have been working with her for months and she has currently found a home. I am just wanting to be sure of income.