Enrolled in Medicare?  If you haven’t already received a new Medicare card, you will soon.

The old cards, which are still valid until December 31, 2019, contain members’ Social Security numbers. In response to a law passed back in 2015, the federal government is issuing new Medicare cards with an 11-character member identifier in place of the Social Security info. The cards are going out from April 2018 through April 2019.

Hopefully the new cards will reduce the risk that someone who gets a hold of your Medicare card will be able to easily steal your identity using your Social Security number, says Sue Greeno, a beneficiary advocate at the Center for Medicare Advocacy

And that’s an important change, since identity theft is a problem that affected 16.7 million people in 2017, up from 12.6 million in 2012, according to research firm Javelin Strategy & Research.

That said, while new Medicare cards are a step in the right direction, they are by no means foolproof. You still need to take care that your new Medicare number doesn’t fall into the wrong hands. Here’s what to keep in mind.

If your new card hasn’t arrived yet

Watch the mail.  Your new card will come via the postal service. Stealing personal information from mail boxes is an old trick, but it’s still a favorite among identity thieves. 

Worried you might not have been on the receiving end of a mailing? First, check here for a list of states that shows where new cards have been sent and where they have yet to go.

If you live in a state on the mailed list but haven’t received your card yet, you can check your Medicare account  (sign up for one at Medicare.gov) to see if yours has been mailed. 

Check your address. The Centers for Medicare and Medicaid Services (CMS), which issues the cards, uses the mailing address for your Social Security account. To update your address, create an online account, or call Social Security at 1-800-772-1213.

If you’re new to Medicare you’ll be automatically issued the new version of the card when you enroll.

If you already have your new card

Keep the number safe. Shredding your old card with a shredder that cross cuts will help protect your Social Security number. But your new Medicare number is still vulnerable to medical identity theft, or when medical insurance information is used to falsely obtain medical care or drugs.

In extreme cases, this could end up mixing your medical records with those of someone else, which can be dangerous and difficult to untangle, says Brian Karimzad, vice president of research at Lending Tree.

Thieves can also use Medicare information to fraudulently bill Medicare in your name for services you never received, putting you at risk of erroneously hitting your maximum coverage limits.

While the new Medicare cards are a step in the right direction, they are by no means foolproof.

Always keep your Medicare card and number in a safe place when you aren’t using it, and disclose it only to trusted medical professionals.

If you are enrolled in Medicare Advantage or have Part D prescription drug coverage, be sure to keep those ID cards and identifying numbers safe as well.

Remember: Medicare isn’t calling. As CMS says on its website: “Medicare will never call you uninvited and ask you to give us personal or private information to get your new Medicare Number and card.”

That doesn’t stop fraudsters from trying, though. Already CMS reports that thieves are calling posing as the federal government and asking consumers for their new ID numbers.

The caller often tells the person answering that their coverage won’t start unless he or she “confirms” the new number. Others are calling and demanding a fee for access to the new Medicare cards, when the cards are free.

If you get a scam call like this, hang up and report it to 1-800-MEDICARE  (1-800-633-4227).

Check your statements. Your best protection from medical fraud of all kinds is to go over your medical bills and explanation of benefit statements carefully for unfamiliar charges. Something seems suspicious? Report it to Medicare or your Medicare Advantage provider immediately.

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