What are 12 things to consider before signing up for Medicare Advantage plans?

Medicare Advantage open enrollment season ends on March 31. There is a lot of information out there about Traditional Medicare and Medicare Advantage—not to mention all the mailers and TV ads—it can be hard to cut through the noise and know what’s most important when choosing a Medicare Advantage plan.

If you’re considering changing your Medicare Advantage plan, or moving over to Traditional Medicare during open enrollment, here’s an essential list of things to do—and not to do—before you make a decision.

1. Do read Medicare’s comprehensive handbook “Medicare & You 2023” (it’s free) and visit Medicare’s website for specifics about Medicare Advantage plans and Traditional Medicare.

2. Don’t miss the open enrollment period for switching Medicare Advantage plans or switching from Medicare Advantage to Traditional Medicare; it ends March 31.

The open enrollment period from October 15 to December 7 is for joining, switching, or dropping a Medicare Advantage plan or a Medicare Part D prescription drug plan.

3. Do understand the difference between Traditional Medicare and Medicare Advantage. Traditional Medicare, sometimes called Original Medicare, is the federal government’s program that lets you use any doctor or hospital that takes Medicare in the U.S. It includes Part A (hospital insurance) and Part B (medical insurance), and you can buy a Medicare prescription drug plan known as Part D and a supplemental Medicare policy known as Medigap. You pay a monthly Part B premium, and if you buy a Part D plan, a monthly premium for that, too.

Medicare Advantage, or Medicare Part C, is the alternative to Traditional Medicare sold by private health insurers. You must use doctors and other health providers in the plan’s network and service area and may need a referral to see a specialist. Some plans have a $0 premium.

4. Do your research to see if you need a Medigap policy if you will be switching to Traditional Medicare. Medigap, or Medicare Supplemental Insurance, is a policy some people with Traditional Medicare buy from private health insurers to pay for some out-of-pocket health costs for medical services and supplies that Medicare covers as well as some services Traditional Medicare doesn’t cover, like health care when traveling abroad.

5. Do get unbiased information about Medicare Advantage and Traditional Medicare by calling your State Health Insurance Program or SHIP. A SHIP advisor won’t direct you to a particular Medicare plan but will be able to explain the basics to help you make a smart decision. “Some counselors may be Medicare beneficiaries themselves, which gives them personal experience with the situations others are going through,” says Susan DeMarois, director of California’s Department of Aging.

6. Do use Medicare’s free Plan Finder tool on its website to compare Medicare Advantage Plans as well as Medicare Part D prescription drug plans and Medigap supplemental policies. The Plan Finder has Medicare’s Star Ratings for Medicare Advantage and Part D prescription drug plans to help you weed out potential choices. These ratings, on a scale ranging from one to five stars (five is the best) measure how well particular Medicare Advantage and Part D plans perform for beneficiaries. If a plan gets fewer than three stars three years in a row, Medicare’s Plan Finder notes it as a “low-performing” plan.

7. Do call your physicians to see which Medicare Advantage plans they, and their hospitals, are in, advises Darwin Hale, CEO and founder of Advocate Health Advisors, a national firm of Medicare brokers.

8. Do find out whether the prescription drugs you take, and their dosage, are covered by the particular Medicare Advantage plan you’re considering, as well as how much they will cost you out of pocket.

9. Do consider working with a Medicare broker to help find Medicare Advantage (as well as Medigap and Medicare Part D) plans. Just understand that brokers generally only sell policies from a select number of companies and always get paid by commission. They do not work for Medicare.

10. Don’t buy a Medicare Advantage plan solely because you saw a TV commercial for one or with a celebrity urging you to call an 800-number. “In a lot of ways, it’s the Wild West when it comes to selling these products,” says David Lipschutz, associate director of the Center for Medicare Advocacy.

11. Don’t choose a Medicare Advantage plan purely because of its premium, says Diane Omdahl, author of Medicare for You: A Smart Person’s Guide. You’ll also want to compare what your annual out-of-pocket limit will be since Medicare Advantage plans have cost sharing for most medical services. “A lot of people get stuck on the premium and pick one Medicare Advantage plan over another without considering all the factors,” says Hale.

12. Don’t forget that if you travel and need a doctor, that physician may not be in your Medicare Advantage plan’s network. As a result, the doctor might not see you.

This story was originally featured on Fortune.com