The four different parts of Medicare are each identified by a letter: A, B, C and D. The number displayed on your Medicare card, however, is known as the Medicare Beneficiary Identifier and is randomly generated for you.
What is the meaning of these Medicare letters? Here we break them down so that you can have a clearer understanding of your Medicare coverage.
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The Medicare number displayed on your red, white and blue Medicare card (known as an MBI, or Medicare Beneficiary Identifier) is 11 characters long:
The MBI is randomly generated and is “non-intelligent,” which means it contains no hidden or special meaning and is therefore more difficult for someone to use to steal your identity or commit fraud.
The four different parts of Medicare are each identified by a letter.
Medicare Supplement Insurance, also called Medigap, uses a letter system to identify its plans. Medicare Supplement Insurance is used in conjunction with Part A and Part B of Medicare to provide coverage for certain out-of-pocket expenses like some Medicare deductibles and coinsurance.
There are 10 Medicare Supplement Plans to choose from, identified by letters: Plan A, B, C, D, F, G, K, L, M and N. Note that Medigap coverage options are referred to as “plan” (e.g., Medigap Plan A) as opposed to “part” (Medicare Part A hospital insurance).
Do you have more questions about Medicare letters? Would you like to speak with a licensed insurance agent who can answer your Medicare questions and help you compare Medicare Advantage plan options available where you live?
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Christian Worstell is a licensed insurance agent and a Senior Staff Writer for MedicareAdvantage.com. He is passionate about helping people navigate the complexities of Medicare and understand their coverage options.
His work has been featured in outlets such as Vox, MSN, and The Washington Post, and he is a frequent contributor to health care and finance blogs.
Christian is a graduate of Shippensburg University with a bachelor’s degree in journalism. He currently lives in Raleigh, NC.
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