Maybe you should “Just say no” the next time a friend or family member asks if you will co-sign on a loan or to get a credit card. Results of a new survey by CreditCards.com reveal that

• 38% of co-signers end up with out of pocket costs because the primary borrower did not pay on the co-signed debt,
• 28% of co-signers had their credit score lowered in exchange for their troubles, and
• 26% of respondents said the relationship was hurt as a result (that gets a big DUH).

On a co-signed obligation, the party with more financial security always has more to lose, which is why co-signing as a “favor” for a person with shaky credit can easily backfire. And since the debt is in the primary borrower’s name, your credit score can be damaged before you even learn that the borrower is behind on payments.

Another mistake is to co-sign for student loans. Doing so for your kids not only relieves them of responsibility but can endanger your retirement security. Help them figure out a budget and explain that they have 40 years to recover from bad decisions but you don’t.

Because student loans are relieved in the event of death,. you should never co-sign for your SO’s student loans. If the worst happens, you don’t want to be dealing with grief and a few hundred thousand dollars in unnecessary debt.