If the Husband, who is the main wage earner or only the person working, and he has terrible credit and the Wife has perfect credit, it won't make any difference adding the Wife. Because she is not contributing financially to the household income, she bring no weight to the loan application. Most likely he will not qualify unless he does some credit repair. It's not like the ole days when people could just state their income on an application and not be required to substantiate their income. We are leaving in a different world now.