The biggest factor is your debt-to-income ratio, or DTI. Lenders compare your total monthly debt obligations against your gross monthly income, and student loan payments count toward that calculation. The catch is that lenders do not always use your actual payment. On conventional loans, when a borrower is on an income-driven repayment plan or has loans in deferment or forbearance, many lenders will use a calculated payment based on the full balance amortized over a standard term, which can be much higher than what you are actually sending each month. FHA takes a different approach and generally allows lenders to use the actual documented payment from your servicer, which is why IDR plans often help FHA borrowers more than conventional ones.
The type of loan you are applying for matters more than most buyers realize. VA loans have their own rules about how to document and calculate student loan payments, and they tend to be more flexible when the borrower can show a history of on-time payments. Conventional loans through Fannie Mae and Freddie Mac have tightened their guidance in recent years, particularly around borrowers with very high balances relative to income. Even a small difference in how your payment is calculated can shift your qualifying amount meaningfully, which is why getting this right before you start house hunting is worth the effort.
There are real strategies that buyers with student debt can use to improve their position. Switching to an income-driven repayment plan can lower the documented monthly payment and improve DTI, though it requires paperwork and a few months of on-time payments before most lenders will accept it. Paying down a chunk of principal before applying reduces both the balance and the calculated payment. For buyers close to the qualifying line, a co-borrower or a different loan program can sometimes make the difference. None of these are quick fixes, but each one has helped move buyers from almost to approved.
Student loan debt is a real factor in mortgage qualification, but it is rarely the deal-breaker people assume it is. With the right loan program, the right repayment plan, and a clear picture of your numbers before you apply, most buyers with student debt can still find a path to homeownership.