Be stingy about giving it out.
"Essentially the Social Security number is the No. 1 key to identity theft. Without a Social Security number, fraudsters are going to be quite limited in what they can do," says Paul Stephens, director of policy and advocacy at the Privacy Rights Clearinghouse. Fraudsters can still access existing accounts, he explains, but it will be hard for them to open new accounts without it.
Learn when you need to disclose your SSN and how you can avoid giving out too much personal information by heeding some simple guidelines.
When not to disclose it
In some situations you should never provide your Social Security number. Doing so may put you at risk of identity theft.
Examples: Beware the unsolicited call, piece of mail or e-mail that asks for personal information in order to verify your identity. Remember that your bank has your Social Security number on file already.
Don't trust your caller ID, either. Criminals can spoof caller ID to make it display a bank's name and phone number, according to Jack Vonder Heide, president and CEO of Technology Briefing Centers.
"If you feel it might be a legitimate call, then call them back at a number that you know to be the correct number for that entity and then provide it," says Stephens.
The confrontationally squeamish need not worry about getting combative. Even if the sheriff calls you, say, "'You know what? I'm going to call back. What's your name and what's your badge number? I will call back and find out if this is really true because that's what I'm advised to do,'" says Mari J. Frank, attorney and author of "Safeguard your Identity."
She says you don't have to get rude -- in fact, you don't want to get feisty in case it's a legitimate call meant to halt fraud.
Never, under any circumstances, provide your Social Security number in an e-mail, even if you initiate the exchange. E-mail is usually unencrypted and anyone can see it, says Stephens.
If a Web site asks for your Social Security number to complete a purchase, don't give it out.
Avoid using public computers or free public Wi-Fi when you need to type in sensitive information. Shared computers may have keystroke loggers on them, which record every key you type. And free public Wi-Fi may connect you to a fake hotspot set up by a hacker.
Tip: "The bottom line is, don't give out information to anybody who calls you or writes you an e-mail or contacts you by mail. Just don't do it," says Frank. Call the entity if you're concerned, using a number verified as authentic.