Definition: A co-signer is an individual other than the borrower who signs a promissory note and in so doing assumes equal liability for it.
Examples:
If you have poor credit a lender may require you to have a co-signer in order to finance the loan. The lender then uses your co-signer’s credit to back up your loan. If you do not pay your loan, the co-signer will be held responsible and the co-signer’s good credit will be on the line.
