Good news! If your friends have strong credit and are solid, upstanding citizens, it might be easier for you to get a loan. That’s because banks and other lenders are increasingly turning to Facebook to get a handle on potential borrowers.

No, they’re not just looking at what you post or share; they’re looking at who your friends are. If you’re hanging around with the right people (read: those with a high credit score), it looks good for you.

And, of course, if a bank knows that you’re a good customer, well, your “friends” might be as well.

From the New York Observer’s Beta Beat:

“There is this concept of ‘birds of a feather flock together,’” said Ken Lin, CEO of the San Francisco-based credit scoring startup Credit Karma. “If you are a profitable customer for a bank, it suggests that a lot of your friends are going to be the same credit profile. So they’ll look through the social network and see if they can identify your friends online and then maybe they send more marketing to them. That definitely exists today.”

So you know how everyone is telling teenagers and 20-somethings to watch what they post to Facebook (because it could cost them a job)? Well, now that applies to seasoned pros as well: Watch what you post to Facebook — and who your friends are — because it could cost you a loan (or get your friends’ mailboxes full of marketing).

But there’s a nightmare scenario: if banks learn how to use social media, they could gather information they aren’t allowed to ask for on a credit application—including race, marital status and receipt of public assistance—or worse, to redline segments of the social graph.

Read the whole story at the Observer, “As Banks Start Nosing Around Facebook and Twitter, the Wrong Friends Might Just Sink Your Credit“.