06/20/2026
Adding a co-borrower changes your entire qualifying picture. Lenders combine both borrowers’ gross monthly income and both borrowers’ monthly debts into one debt-to-income (DTI) calculation — so a co-borrower only helps if their income improves the blended ratio after their debts are included. A partner with significant monthly obligations can actually raise the combined DTI instead of lowering it. Before bringing someone onto the loan, run the numbers: (your gross monthly income + their gross monthly income) ÷ (all monthly debts + projected mortgage payment). If the result falls below your program’s DTI threshold, the co-borrower helps. If it stays the same or increases, adding them may not achieve your goal. Bottom line: do the math first, then decide. Ken Claude | SC Real Estate Broker-in-Charge & Licensed Loan Officer | Carolina Coastal Realty Group, LLC | Summit Lending Group | NMLS #2476547 | 843-900-1254 | Equal Housing Lender | Powered by C2 Financial Corporation.