This just in: No good deed goes unpunished. 

“If you co-sign with someone on a loan or a credit card, you’ve got a 40 percent chance of losing money and a 26 percent chance of damaging your relationship,” said Matt Schultz, senior industry analyst at CreditCards.com. It commissioned a survey of 2,003 adults of whom 388 had co-signed a loan. 

The conclusion: Never help anyone ever. 

“Twenty-eight percent experienced a drop in their credit score because the other person paid late or not at all,” Schultz said.

That drop in credit score can cost a co-signer for decades, worsening the terms of everything from car loans to mortgages. 

Jill Schlesinger, a CBS News business analyst and certified financial planner, said that perhaps it’s OK to help people out in certain circumstances. 

“Your child, who has a very good job but doesn’t have enough credit history to purchase, say, an apartment? OK, I can live with that,” she said.  

Co-signers might be wise to take a trust-but-verify approach, demanding to have access to all relevant accounts so they can monitor the finances of the person they’re supporting.

In general, Schlesinger said, “If someone cannot get a loan, usually there’s some reason behind it. If a lender isn’t willing to extend money, why should you?”

Ultimately, don’t offer to help someone get a loan unless you’re willing to pay that loan back yourself.