A Medicare Evidence of Coverage (EOC) notice is a document that a person’s Medicare Advantage (Part C) plan or Medicare Part D plan sends to them each year.

The document contains important information about the plan’s benefits and payments. It may help a person decide whether they want to keep or change their health insurance coverage.

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An EOC document is a detailed explanation of each aspect of a person’s medical insurance policy. It includes information about costs, coverage, access to certain services, and a person’s rights as a member of a certain health plan.

Insurance companies usually send an EOC document to policyholders in September.

Glossary of Medicare terms

  • Out-of-pocket cost: This is the amount a person must pay for care when Medicare does not pay the total amount or offer coverage. Costs can include deductibles, coinsurance, copayments, and premiums.
  • Premium: This is the amount of money someone pays each month for Medicare coverage.
  • Deductible: This is an annual amount a person must spend out of pocket within a certain period before Medicare starts to fund their treatments.
  • Coinsurance: This is the percentage of treatment costs that a person must self-fund. For Medicare Part B, coinsurance is 20%.
  • Copayment: This is a fixed dollar amount a person with insurance pays when receiving certain treatments. For Medicare, this usually applies to prescription drugs.

Medicare requires companies that offer Part C (Medicare Advantage) plans and Part D (prescription drug) plans to send an EOC once per year. But a person enrolled in Original Medicare (parts A and B) will not get an EOC notification.

Companies send EOC documents in September because the Medicare open enrollment period (OEP) runs from October 15 to December 7. This gives a person sufficient time to review any plan changes.

If a person does not like the plan changes or wants to switch plans, they can do so during the OEP. If they wish to keep their current plan, they do not have to do anything because their plan will automatically reenroll them.

Learn about the pros and cons of Medicare Advantage plans, and get more information about Part D plans.

Some EOC documents can be more than 100 pages in length. They generally include the following information:

  • Costs: An EOC should include an explanation of the policy’s costs, including monthly premiums, copays for doctor’s visits, and coinsurance percentages when a person seeks certain health services.
  • Emergencies: An EOC should outline some of the instances that are considered a medical emergency and explain when the plan will pay for care. This section may describe coverage if a person seeks emergency care for a problem that is not a medical emergency.
  • In-network vs. out-of-network payments: The EOC should explain the key differences in costs (such as copays) when a person gets care from an out-of-network professional.
  • Noncovered services: Just as an EOC will list covered services, it will also list those that the plan does not cover.
  • Directions to a listing of in-network providers and pharmacies: An EOC will include how a subscriber can find the plan’s list of in-network professionals, facilities, and pharmacies. A person generally gets the greatest cost savings by choosing in-network professionals, facilities, and pharmacies.
  • Directions for filing a grievance or appeal: An EOC will also include information on how to file an appeal if the plan rejects payment for a particular service and how to file a grievance with the health plan. A grievance is a complaint regarding the plan’s services or the provider’s customer service.

Other key EOC elements may include rights and responsibilities, legal notices, instructions on ending a person’s membership, and definitions of key terms.

Insurance companies will typically make these documents available in paper format or online. If, for any reason, a person misplaces or loses a portion of their EOC document, they can request a new one from their plan provider.

A person will usually get their member identification card together with their EOC from either their Medicare Advantage (Part C) plan provider or their Medicare Part D plan provider.

A person should note that an EOC for a prescription drug plan does not usually include the plan’s prescription drug list, called a formulary. A person can request a paper copy of the formulary, though.

Most commonly, the EOC describes potential benefit changes and overall benefits that become effective on January 1 of the following year.

For example, if a person gets an EOC notice in September 2024, they can expect the benefits that the EOC outlines to take effect starting on January 1, 2025.

If a person has specific questions regarding health plan changes or the wording of something in their EOC, they can ask their plan provider to explain it to them.

Such details may include how an insurance company defines or reimburses some services. Contact phone numbers should be in the EOC document.

Providers of Medicare Advantage and Part D plans send out an EOC document in September each year.

It provides details of plan coverage, benefits, and costs. A person should contact their plan provider if they do not get an EOC in September.