It’s that time of year again when the nation’s 54 million Medicare beneficiaries have the chance to swap Medicare Advantage and Part D prescription drug plans during Medicare’s annual open enrollment period.

In addition to the challenge of sifting through the dizzying array of plan options, experts say Medicare open enrollment is also prime time for Medicare scams.

“Right now … everyone is being inundated with TV commercials, brochures and other official-looking documents in the mail about all the Medicare Advantage plans. It’s so confusing and in an environment like that, fraud is rampant,” says Micki Nozaki of the California Senior Medicare Patrol, which is part of a nationwide network of outreach and education programs that work to prevent and report health care fraud.

There are a few quick tips when it comes to protecting yourself against scams, experts say.

First is to guard your Medicare number — which in most cases is your Social Security number — the same way you would protect your bank and credit card information. Don’t give it to anyone you don’t know for certain is part of your health care team.

“That Medicare number is precious and should not be given under any circumstances,” says Ronald Bolding, president of Inter Valley Health Plan, which sells Medicare Advantage plans.

Second, keep in mind that Medicare will never call or email you with product offers.

“The moment you get a call or email asking for your [Medicare] number by someone claiming they’re from Medicare, you’re dealing with an automatic scam,” says James Quiggle, director of communications at the nonprofit Coalition Against Insurance Fraud. That should be an immediate tip-off to hang up the phone, he says.

Also, if an insurance agent calls or visits your home to sell or endorse any Medicare product, he or she is acting illegally. “If someone comes to your door and they haven’t set up an appointment or been invited, that’s an abuse,” Bolding says.

Finally, keep an eye out for these five common Medicare open enrollment scams:

1. Switching plans is a must. According to Nozaki, one common scam involves insurance agents telling you that open enrollment isn’t just an opportunity to change your Medicare Advantage and Part D prescription drug plans, it’s a must, and that failing to do so could cause you to lose your current coverage.

Although experts say shopping your options each year is the best way to ensure you’re still covered by the best plan for you, you’re entitled to stay with your current policy and not make any changes at all if that’s your preference.

“Don’t ever believe somebody who says you have to change your Medicare Advantage or Part D prescription drug plan,” Nozaki says.

Once you give them your Medicare number, nefarious insurance agents then enroll you in a plan that doesn’t suit your needs.

“[Scam victims] find out later they can’t see their doctor or get their medication,” Nozaki says. “Or worse, the agent obtains their information and enrolls them in a plan without their knowing it.”

2. Medicare is changing cards. Quiggle says to be on the lookout for anyone who tells you Medicare cards are changing and that to get your new card you just need to update your information.

The common line, he says, is to tell you that you “just need to update [your] file with credit card information and Social Security information so Medicare can issue [you] a new card.”

It’s a scam. Again, Medicare will never call you or show up at your door — or ask you for personal information via email.

3. For you, a special price. High-pressure pitches for Medicare insurance policies that come with especially low costs are common during open enrollment.

Here’s how it goes down: Insurance agents tell seniors that for a limited time, they can sign up for an early bird discount — which amounts to a much lower monthly premium for a particular health plan. “Most of the time it’s B.S.,” Nozaki says.

To shop for or enroll in legitimate Medicare Advantage or Part D prescription drug plans, check out the Medicare plan finder at http://www.medicare.gov or call 800-MEDICARE, or 800-633-4227.

For free personalized counseling services, contact your State Health Insurance Assistance Program at shipnpr.shiptalk.org, or call 800-677-1116.

4. Health fair scams. Health fairs or other events that take place during Medicare open enrollment can be ripe with opportunities for fraud.

A common tactic by vendors with bad intent is to staff a table at a health fair and advertise a free gift, like nutrition supplements. To enter into a drawing for a free prize, you’ll be asked to sign up by giving your name and Medicare number, and to come in back in a little while to see if you’ve won.

“If you go to a senior’s fair, there is no reason you should give your Medicare number to a vendor for a free prize,” Nozaki says.

5. Phony organizations. Finally, experts say to be on the alert for any calls from people saying they’re from your doctor’s office, or state or local health agencies that are often given a phony, official-sounding name.

Sometimes crooks will get illegal access to your medical information from your doctor’s office and call with enough detail about your personal situation to lure you into sharing more personal details that can lead to fraud.

“They drop information like a fortune teller,” says Elizabeth T. Gutierrez, who helps seniors who have been victims of Medicare fraud with the Family Care Specialists Medical Group.

“They throw out key words and know the chances of a senior being diabetic or overweight are pretty good … and then say ‘I’m not sure your doctor is taking care of you the way he should,'” she says.

That’s when they try to convince you to give up your Medicare number so they can switch you to a plan in which their doctors participate.

“What’s happening is the brokers are hungry” for money, Gutierrez says.

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How to Protect Yourself Against Common Medicare Scams originally appeared on usnews.com