What Is a Co-Signer?
A co-signer is a person who signs a loan alongside the main borrower and agrees to repay it if the borrower does not. Lenders may require a co-signer when the borrower has limited credit history or income. The loan typically appears on the co-signer’s credit report as well.
Responsibilities
The co-signer is legally responsible for the full debt. Missed payments can affect both people’s credit, and the loan counts toward the co-signer’s debt when they apply for credit.
Co-Signer vs. Co-Borrower
A co-borrower shares ownership of what the loan buys; a co-signer usually does not, but still shares the obligation.
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🔗 Related Terms
More Loans & Credit Terms
- Amortization
- APR (Annual Percentage Rate)
- Balance Transfer
- Balloon Payment
- Buy Now, Pay Later (BNPL)
- Cash Advance
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Last updated: September 29, 2026. This definition is for general educational purposes only. It is not financial, investment, tax, legal, or medical advice, and it does not recommend any product or course of action. For decisions about your own situation, consult a qualified professional.