Your Social Security number is your most important means of federal identification. Unfortunately, that means if someone gets ahold of that number, they can wreak havoc on your life. Here's how to keep your Social Security number safe.

1. Don't carry your card

The worst place for your Social Security card is in your wallet. If your wallet is stolen or misplaced, your Social Security number could end up in a fraudster's possession. Instead, keep your card in a secure location. A safe deposit box at your local bank would be an excellent choice, and you could keep other important financial documents there as well. If you don't want to get a safe deposit box, consider acquiring a fireproof and waterproof home safe or lockbox to keep your critical documents protected.

Faceless hacker in hoodie

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2. Use it only when you have to

The more often you disclose your Social Security number, the more likely it is that that number will escape into the wild. Sometimes you'll have no choice but to give it out; for example, if you apply for a loan you will almost certainly have to give the lender your number so your credit report can be pulled. Shred any documents containing sensitive financial information, especially those that include your Social Security number; fraudsters have been known to retrieve all kinds of useful information from dumpsters and curbside recycling bins.

By federal law, state tax authorities and government agencies (including the DMV) are allowed to ask you for your Social Security number for identification purposes. And if you make a cash transaction over $10,000, the bank will require your Social Security number so it can report the transaction to the IRS. But for other requesters, getting your Social Security number may just be a convenience -- and if you ask, they may allow you to use other means of identification. And never give out your Social Security number to a stranger who calls or emails asking for it, no matter who they claim to be.

3. Don't make it digital

Once your Social Security number gets on the Internet, there's no telling who will get ahold of it. Never include your Social Security number in an email or social media post (and that includes emailing documents with your Social Security number on them). If a website asks for your Social Security number, don't enter it unless you're positive that the site is using encryption to protect your information. Check that the website's address in your browser's address bar starts with "https," not "http." Most browsers will also include a lock icon in the address bar if you're on a secure site.

4. Be on the lookout

It's important to watch for signs of identity theft; the earlier you catch such problems, the less damage they'll create in your life. Check your credit report on a regular basis (once a year at a bare minimum) and take action if any red flags show up on it, like accounts that you don't remember opening or mysterious charges on your existing accounts. An identity theft protection service can also help by monitoring your accounts for suspicious activity.

Other common signs of identity theft include suddenly not getting any mail (fraudsters will often put in a change of address request for their victims), debt collection calls on accounts you don't recognize, problems with your health insurance (including claims you don't recognize and medical records that include a condition you don't have), and IRS notices saying that you have income from an employer you don't work for or multiple tax returns for the year. If any of these red flags pop up, report them immediately on the Federal Trade Commission's identity theft website. Depending on the scope and nature of the problem, you may also need to notify the IRS, the police, and/or the appropriate state agency. Recovering from identity theft can take months or even years, so the best course of action is to protect yourself to keep it from happening in the first place.

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