Does Medicare Cover Preexisting Conditions?

The answers are “yes,” “mostly,” and “it depends,” depending on the Medicare program. See the differences in how each program covers pre-existing conditions below
Alex Enabnit
Licensed Insurance Agent and Medicare Expert Writer
December 12, 2019

Pre-existing condition refers to any health condition (such as cancer, diabetes, or heart disease) you have before joining a health plan. Before the Affordable Care Act of 2014, discrimination against individuals with pre-existing conditions wasn’t uncommon in the private health sector. Fortunately, that isn’t always true anymore in the case of private health insurance.

On the other hand, with Medicare, pre-existing conditions have typically never been taken into consideration when inviting enrollees into the fold. There’s just one exception: individuals with End-Stage Renal Disease (ESRD) get a whole different set of rules with Medicare and Medicare Advantage. We’ll get into that in just a minute.

Does Medicare, Medicare Advantage, and Medigap Cover Pre-Existing Conditions?

Short Answer: Yes

Original Medicare
Medicare Advantage
Yes.For the most part.Yes-if you time it right.

Medigap (Medicare Supplement) is a different beast, with its own unique rules for pre-existing conditions. Skip ahead to that section if you already know you’re looking for a Medicare Supplement plan.

Does Original Medicare cover pre-existing conditions?

Original Medicare doesn’t turn people down for health care coverage based on pre-existing conditions—period. However, they do make a few special rules for people who have End-Stage Renal Disease (ESRD). While most people under 65 must collect Social Security disability for 24 months before they are automatically enrolled in Medicare, those with ESRD get an automatic pass to the front of the line. No matter the individual’s age, Medicare coverage for people who have ESRD generally begins after a patient has been on dialysis for four months. If you have ESRD, read the requirements and your eligibility on

Does Medicare Advantage cover pre-existing conditions?

Yes, Medicare Advantage welcomes anyone with pre-existing conditions—besides End-Stage Renal Disease (ESRD).

If you have ESRD, you won't be able to join a Medicare Advantage plan except in a few particular circumstances:

  • If you were in the Medicare Advantage plan when your ESRD was diagnosed
  • If, through a kidney transplant, you no longer need dialysis but still need Medicare
  • If you’re on a health plan with a company that also offers a Medicare Advantage plan
  • If you find a Medicare Advantage Special Needs Plan specifically for ESRD (more on that below)

If you have ESRD and want to join Medicare Advantage, your best bet may be to find a Medicare Advantage Special Needs Plan (SNP). SNPs are Medicare Advantage plans designed and qualified to treat groups of people with similar illnesses, economic status, or living situations. The availability of these plans varies based on your location, but an experienced representative can help you find out what your SNP options are.

Does Medigap (Medicare Supplement) insurance cover pre-existing conditions?

Medigap (also known as Medicare Supplement) is supplemental insurance you can purchase to complement your Original Medicare coverage. Medigap plans increase your coverage for costs under Original Medicare such as copays, deductibles, coinsurance, and others, depending on which plan you purchase.

Medigap plans are regulated by the federal government and sold by private insurance companies. As such, Medicare offers protections for people who purchase a Medicare Supplement plan, most commonly during a specific timeframe—the six months after you apply for Part B at age 65 (or whenever you sign up for Part B after 65). This once-in-a-lifetime period is the critical time to buy a Medigap policy because, besides this window, there are typically only a few other scenarios where you have protections for pre-existing conditions.

This six-month period, called the Medigap Open Enrollment Period (MOEP), ensures the insured won’t be subject to medical underwriting (medical underwriting is a fancy way to say, “discriminated against based on health”). Outside of that six-month window after you sign up for Part B, insurance companies have the liberty to medically underwrite your policy based on pre-existing conditions (except for in a few states or in select circumstances).

Here are a few examples of the medical underwriting allowed by Medigap issuers if you buy a Medigap plan outside of your 6-month MOEP:

  • A company may charge you more for a policy.
  • A company may require you to wait up to six months before your policy begins.
  • A company may deny you a policy altogether.

There is one tricky bit of fine print regarding pre-existing conditions during the MOEP, however.

Can there still be a waiting period for Medigap, even if I get it within six months of signing up for Part B?

Even if you get a Medigap policy within your six-month Medigap Open Enrollment Period, insurance companies are legally allowed to make you wait for coverage to begin in one specific situation: if you have a pre-existing condition that was diagnosed (or you received treatment for it) in the last six months, they are allowed to delay coverage for treatments based on that pre-existing condition.

So, for example, if you were diagnosed with diabetes two months before applying for Medigap, the insurance company may choose not to cover copays or deductibles for diabetes treatments for up to six months. Keep in mind, however, that doesn’t mean you don’t have coverage for your pre-existing condition. Since Medigap supplements Original Medicare, your pre-existing condition will still be covered by Medicare. But your copays, deductibles, or coinsurance costs may be on you.

However, there is a way to avoid—or at least reduce—this waiting period.

How do I avoid the Medigap waiting period for pre-existing conditions?

Two words: creditable coverage.

Creditable coverage is health coverage that is at least as good as Medicare, such as from an employer or other group plans.

If you have coverage from an employer, for example, for at least six months leading up to your Medicare enrollment, you won’t be subjected to a waiting period for pre-existing conditions. If your previous coverage lasted less than six months before you get Medigap, your waiting period would deduct your months of creditable coverage from your overall waiting period.

So, in another example, if your previous coverage only lasted for three months before you get Medigap, your waiting period would most likely be the six-month maximum minus your three months of creditable coverage. As a result, you’d have a three month waiting period.

For previous medical coverage to count, there can’t be a gap of longer than 63 days between your previous coverage and your Medigap policy beginning, so time is of the essence. You must also verify that your last coverage was creditable, which you can usually check through your Medigap company.

What if I didn’t enroll in Medigap during my Medigap Open Enrollment Period?

It’s pretty clear the best time to buy a Medicare Supplement plan is during your Medigap Open Enrollment Period, when you can’t be discriminated against for a Medigap policy based on your health. But if you missed that window, what should you do?

If you have pre-existing conditions, your chances of getting a Medigap policy (or the one you want) after the MOEP ends may seem bleak, but that’s not necessarily the case. First, check to see if you could qualify for a Special Enrollment Period (SEP), which comes with Medigap protections—meaning you wouldn’t be subject to medical underwriting. Read more about these scenarios on

But say you don’t qualify for Medigap protections. Then what? Here are a few possible outcomes if you apply for a policy, as well as some of your options:

1. The insurance company quotes you at a higher price for a Medigap policy.

If this is your situation, consider whether you can afford the higher price. If you can, go for it.

You could also get quotes for the same plan from other companies, which may offer it for a different (lower) price.

Another option is to consider a Medigap plan that doesn’t offer as many benefits, which will generally result in lower premiums.

You can do all this plan comparison on your own, but it may be easier to call a representative—see the number below if that’s your preferred method.

2. The insurance company is imposing a waiting period for your coverage to begin.

The insurance company could make you wait up to six months before your Medigap coverage starts for certain pre-existing conditions, but no longer. In that time, Medicare still covers your pre-existing condition, but you’ll be on the hook for any deductibles, copays, or coinsurance your plan might have taken care of. Unfortunately, there’s not a lot you can do in this situation besides wait it out.

3. The insurance company denied you a policy.

You can try again with another company and see if they’ll sell you a policy. If that doesn’t work, perhaps look into Medicare Advantage, which cannot deny you a plan (unless you have End-Stage Renal Disease). Additionally, many Medicare Advantage plans come with Part D prescription drug coverage and may even add benefits Original Medicare doesn’t offer—vision, dental, hearing, or a fitness membership, just to name a few.

The bottom line

When it comes to covering pre-existing conditions, Medicare offers enrollees generous coverage.

To see if a Medigap or Medicare Advantage plan could be a good fit for you, call an agent.

Content on this site has not been reviewed or endorsed by the Centers for Medicare & Medicaid Services, the United States Government, any state Medicare agency, or any private insurance agency (collectively "Medicare System Providers"). is a DBA of Clear Link Technologies, LLC and is not affiliated with any Medicare System Providers.

Alex Enabnit
Written by
Alex Enabnit
Medicare and geriatric care expert, Alex has one motivation behind every word he writes, and that’s finding you the best medical coverage for your situation. Alex has been featured on Bloomer Boomer, Best Company,, the Daily Ledger on the One America News Network, WBAP News radio, and more. Outside of work, you can find him hiking with his wife and pup or (occasionally) going to the gym.
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