What is Medicare?
Medicare is a health insurance program run by the U.S. government. It helps people who are 65 years old or older pay for their medical care. Some younger people with disabilities can also get Medicare. This program started in 1965 and has helped millions of Americans get the healthcare they need without going broke.
Many people get confused about Medicare because it has different parts and options. This guide will explain everything so you can understand how Medicare works and what it covers.
Who Can Get Medicare?
Most people become eligible for Medicare when they turn 65 years old. But age is not the only way to qualify. Here are the main groups of people who can get Medicare:
People 65 and Older : If you are 65 or older and you or your spouse worked and paid Medicare taxes for at least 10 years, you can get Medicare.
People with Disabilities : If you are under 65 but have been getting Social Security Disability Insurance (SSDI) for 24 months, you can get Medicare.
People with Specific Diseases : Some people with kidney failure (called End-Stage Renal Disease or ESRD) or ALS (also called Lou Gehrig’s disease) can get Medicare right away, even if they are younger than 65.
The good news is that if you already get Social Security benefits when you turn 65, you will automatically get signed up for Medicare. You don’t have to do anything special.
The Four Main Parts of Medicare
Medicare is divided into four parts: Part A, Part B, Part C, and Part D. Each part covers different types of healthcare services. Think of them like pieces of a puzzle that work together to give you full coverage.
Part A – Hospital Insurance
Part A is sometimes called hospital insurance. It pays for care when you need to stay in a hospital overnight. It also covers some other types of care.
Part B – Medical Insurance
Part B is medical insurance. It pays for doctor visits and other medical services you get as an outpatient, which means you don’t stay overnight in the hospital.
Part C – Medicare Advantage
Part C is also called Medicare Advantage. These are plans sold by private insurance companies that include everything in Part A and Part B, plus extra benefits.
Part D – Prescription Drug Coverage
Part D helps pay for the medications your doctor prescribes that you pick up at the pharmacy and take at home.
What Does Medicare Part A Cover?
Part A covers medical care when you need to stay somewhere overnight or need serious medical help. Here is what Part A pays for:
Hospital Stays : When you need to stay in the hospital as an inpatient, Part A covers your room, meals, nursing care, and medicines you get while you are there.
Skilled Nursing Facility Care : After a hospital stay, if you need rehabilitation or skilled nursing care, Part A can cover up to 100 days in a skilled nursing facility. This is not the same as a nursing home for long-term living.
Hospice Care : If you have a terminal illness and choose hospice care, Part A covers this service. Hospice focuses on comfort and quality of life rather than curing the illness.
Home Health Care : Part A covers some home health services if you need medical care at home after being in the hospital.
Blood Transfusions : If you need blood during a hospital stay, Part A covers this after the first three pints.
Part A does not cover everything though. It does not pay for long-term care in a nursing home if you just need help with daily activities like eating or bathing. It also does not cover private rooms in hospitals unless medically needed.
How Much Does Part A Cost?
Most people do not pay a monthly premium for Part A if they or their spouse worked and paid Medicare taxes for enough time. Here is how it works:
| Work History | Monthly Premium in 2026 |
| 40 quarters or more (about 10 years) | $0 |
| 30 to 39 quarters | $311 |
| Less than 30 quarters | $565 |
Even if you don’t pay a monthly premium, Part A still has other costs you need to know about.
Deductible : In 2026, you pay $1,736 as a deductible for each benefit period. A benefit period starts when you enter the hospital and ends when you have been out of the hospital or skilled nursing facility for 60 days in a row.
Copayments for Long Stays : If you stay in the hospital for more than 60 days, you start paying copayments. The longer you stay, the more you pay each day. These costs can add up, which is why many people get extra insurance to help cover them.
What Does Medicare Part B Cover?
Part B covers medical services and supplies you need to stay healthy or treat health problems, but you don’t have to stay overnight in a hospital. This includes:
Doctor Visits : Regular checkups with your family doctor or visits to specialists are covered by Part B.
Preventive Services : Part B covers many free preventive services like flu shots, cancer screenings, diabetes checks, and wellness visits to help catch health problems early.
Outpatient Care : Medical care you get in a hospital or clinic without staying overnight is covered.
Medical Equipment : Durable medical equipment like wheelchairs, walkers, hospital beds, and oxygen equipment are covered if your doctor says you need them.
Lab Tests and X-rays : Blood tests, urine tests, X-rays, MRIs, and other diagnostic tests are covered.
Mental Health Services : Counseling and therapy for mental health conditions are covered by Part B.
Ambulance Services : Emergency ambulance rides are covered when other transportation could harm your health.
Second Opinions : If your doctor recommends surgery, Part B covers getting a second opinion from another doctor.
Part B does not cover prescription drugs you pick up at the pharmacy. For that, you need Part
- It also does not cover dental care, eye exams for glasses, or hearing aids in most cases.
How Much Does Part B Cost?
Unlike Part A, everyone pays a monthly premium for Part B. In 2026, the standard premium is
$202.90 per month. However, if you have a higher income, you might pay more.
Deductible : You pay the first $283 of medical costs in 2026 before Part B starts paying its share.
Coinsurance : After you meet the deductible, you typically pay 20% of the Medicare-approved amount for most services. Part B pays the other 80%.
Let me give you an example. Say you go to the doctor and the visit costs $100. If you already met your deductible, you would pay $20 and Part B would pay $80.
The 20% coinsurance can get expensive if you need a lot of medical care, which is why many people choose to get extra coverage through a Medigap plan or Medicare Advantage.
Understanding Medicare Part D
Part D plans help you pay for prescription medications you take at home. These are drugs your doctor prescribes that you pick up at the pharmacy.
Private insurance companies run Part D plans, so the costs and which drugs are covered can be different from one plan to another. Every Part D plan has a list of covered drugs called a formulary. Before you choose a plan, check if your medications are on the formulary.
What Part D Covers
Part D covers most prescription drugs, including:
- Brand-name drugs
- Generic drugs
- Vaccines (some are covered by Part B instead)
- Insulin and diabetes supplies
Each plan must cover at least two drugs in each category and class. Some drug classes are “protected,” which means the plan must cover nearly all drugs in those categories. Protected classes include drugs for cancer, HIV/AIDS, mental illness, seizures, and transplant rejection.
Part D Costs
The costs for Part D depend on which plan you choose. In 2026, the base premium is $38.99 per month, but many plans charge more. If you have a high income, you might pay an extra amount on top of your plan premium.
Here is what you might pay with a Part D plan:
| Cost Type | Amount in 2026 |
| Monthly Premium | Starts at $38.99 (varies by plan) |
| Deductible | Up to $615 (some plans have no deductible) |
| Coinsurance | 25% after deductible |
| Out-of-Pocket Maximum | $2,100 |
After you pay your deductible, you pay 25% of the cost of your drugs and the plan pays 75%. Once you have paid $2,100 out of your own pocket in a year, you pay nothing more for drugs for the rest of that year. This is a new rule that started in 2025 and really helps people who take expensive medications.
What is Medicare Advantage (Part C)?
Medicare Advantage plans, also called Part C, are an alternative way to get your Medicare benefits. Private insurance companies approved by Medicare offer these plans.
A Medicare Advantage plan gives you all the benefits of Part A and Part B in one plan. Most Medicare Advantage plans also include Part D prescription drug coverage. Some plans offer extra benefits that Original Medicare does not cover.
Extra Benefits in Medicare Advantage
Many Medicare Advantage plans include:
- Prescription drug coverage (Part D)
- Dental care (cleanings, fillings, dentures)
- Vision care (eye exams, glasses, contacts)
- Hearing services (hearing tests, hearing aids)
- Fitness programs (gym memberships)
- Transportation to doctor appointments
- Over-the-counter items allowance
These extra benefits make Medicare Advantage attractive to many people. However, there are some trade-offs you should know about.
How Medicare Advantage Plans Work
Medicare Advantage plans usually work like HMOs or PPOs. This means:
Network Restrictions : You typically need to use doctors and hospitals in the plan’s network. If you go to an out-of-network provider, you might have to pay the full cost yourself.
Referrals : Some plans require you to get a referral from your primary care doctor before seeing a specialist.
Prior Authorization : The plan might need to approve certain services or procedures before you can get them.
Geographic Limits : Your coverage usually only works in a specific area. If you travel a lot or live in different states at different times of the year, this could be a problem.
The costs for Medicare Advantage plans vary widely. Some plans have $0 monthly premiums, while others charge a premium on top of your Part B premium. You still have to pay your Part B premium even if you choose Medicare Advantage.
What is Medigap (Medicare Supplement)?
Medigap is not actually a part of Medicare, but it is an important option to know about. Medigap plans are sold by private insurance companies and help pay for the out-of-pocket costs that Original Medicare does not cover.
If you have Original Medicare (Parts A and B), you are responsible for deductibles, coinsurance, and copayments. These costs can add up quickly. A Medigap plan helps pay for these expenses so you have more predictable healthcare costs.
Types of Medigap Plans
There are 10 standardized Medigap plans available in most states: Plans A, B, C, D, F, G, K, L,
M, and N. Each plan offers a different level of coverage. Plan F and Plan G also come in high-deductible versions.
The benefits in each plan type are the same no matter which insurance company sells it. For example, Plan G from one company covers the same things as Plan G from a different company. The only difference is the price.
Important Rule : If you became eligible for Medicare after January 1, 2020, you cannot buy Plan C or Plan F. These plans are only available to people who were eligible for Medicare before that date. Plans D and G offer similar coverage if you need an alternative.
When to Buy Medigap
The best time to buy a Medigap plan is during your Medigap Open Enrollment Period. This is a 6-month period that starts when you are 65 or older and enrolled in Part B.
During this time, you have guaranteed issue rights. This means insurance companies cannot deny you coverage or charge you more because of health problems. If you wait and try to buy Medigap later, you might face medical underwriting, higher prices, or even denial of coverage.
Comparing Original Medicare and Medicare Advantage
Choosing between Original Medicare with a Medigap plan or Medicare Advantage can be confusing. Here is a comparison to help you understand the differences:
| Feature | Original Medicare + Medigap | Medicare Advantage |
| Coverage | Parts A and B, plus Medigap supplement | Parts A and B combined, often includes Part D |
| Extra Benefits | Usually need separate Part D plan | Often includes dental, vision, hearing |
| Doctor Choice | See any doctor who accepts Medicare | Usually must use network doctors |
| Costs | Part B premium + Medigap premium + Part D premium | Part B premium + plan premium (sometimes $0) |
| Travel | Works anywhere in the U.S. | Usually limited to plan service area |
| Referrals | Not needed | Sometimes needed for specialists |
Neither option is better than the other. It depends on your personal situation, health needs, budget, and preferences.
How to Sign Up for Medicare
Signing up for Medicare is usually straightforward, but you need to know when and how to do it.
Automatic Enrollment
If you are already getting Social Security benefits when you turn 65, you will be automatically enrolled in Part A and Part B. You will get your Medicare card in the mail about three months before your 65th birthday.
If you don’t want Part B (maybe because you still have employer insurance), you can send the card back with a note saying you want to decline Part B.
Manual Enrollment
If you are not getting Social Security benefits, you need to sign up yourself. You can do this during your Initial Enrollment Period.
Initial Enrollment Period : This is a 7-month period that includes:
- The 3 months before your 65th birthday month
- Your birthday month
- The 3 months after your birthday month
For example, if your birthday is in June, your Initial Enrollment Period would be from March through September.
How to Apply
There are three ways to apply for Medicare:
- Online : Go to the Social Security Administration website and use their online application. This is the fastest and easiest way.
- By Phone : Call Social Security at 1-800-772-1213 (TTY: 1-800-325-0778). You can call Monday through Friday, 8:00 a.m. to 7:00 p.m.
- In Person : Visit your local Social Security office. You can find the nearest office on the Social Security website.
Special Note : If you worked for the railroad and are retired, you should contact the Railroad Retirement Board instead at 1-877-772-5772 (TTY: 312-751-4701).
Special Enrollment Periods
If you miss your Initial Enrollment Period, you might face late enrollment penalties and a gap in coverage. However, you might qualify for a Special Enrollment Period in certain situations.
Common reasons for Special Enrollment Periods include:
- You have health insurance through your employer or your spouse’s employer
- You are moving out of your plan’s service area
- You lose your current health coverage
- You move back to the U.S. after living abroad
- You are released from prison
If any of these apply to you, contact Medicare or Social Security to find out if you can enroll outside the regular enrollment period.
Choosing the Right Medicare Plan
Picking the right Medicare coverage is a personal decision. What works great for your neighbor might not be the best choice for you. Here are some things to think about:
Look at Your Healthcare Needs
Make a list of your current health conditions. Do you have diabetes, heart disease, arthritis, or other ongoing health problems? How often do you see doctors? Do you take regular medications?
People who are generally healthy might want a plan with lower premiums and are okay with paying more if they need care. People with chronic conditions might prefer a plan with higher premiums but lower costs when they use services.
Check Your Doctors
If you have doctors you really like and trust, find out if they accept Medicare. Also ask which Medicare Advantage plans they work with if you are considering that option.
Going to a new doctor can be stressful, especially if you have been seeing the same doctor for years. Make sure your preferred doctors are covered before you choose a plan.
Consider Your Budget
Add up all the costs, not just the monthly premium. Include:
- Monthly premiums for Part B, Part D, Medigap, or Medicare Advantage
- Deductibles
- Coinsurance and copayments
- Prescription drug costs
Try to estimate how much you spent on healthcare last year. This can help you predict which plan will save you money.
Think About Extra Benefits
Do you need dental work? Do you wear glasses or hearing aids? Would you use a gym membership if it was included?
If these extra benefits are important to you, Medicare Advantage might be worth considering. However, remember that you might have less flexibility in choosing doctors.
Plan for the Future
Think about medical care you might need in the coming year. Are you planning any surgeries? Will you need physical therapy? Are you at risk for certain health conditions? Also think about your lifestyle. Do you travel often? Do you spend winters in a different state? Make sure your coverage will work wherever you are.
What Medicare Does Not Cover
Medicare covers a lot, but not everything. Here are some important things Medicare does not pay for:
Long-Term Care : Medicare does not cover custodial care in nursing homes. If you just need help with daily activities like bathing, dressing, or eating, you will have to pay for this yourself or get long-term care insurance.
Dental Care : Original Medicare does not cover routine dental care like cleanings, fillings, or dentures. Some Medicare Advantage plans include dental benefits.
Eye Exams for Glasses : Medicare covers some eye exams to check for diseases, but it does not cover routine eye exams to get glasses or contacts. It also does not cover eyeglasses or contact lenses (except after cataract surgery).
Hearing Aids : Medicare does not cover hearing aids or exams for fitting hearing aids. Some Medicare Advantage plans include hearing benefits.
Cosmetic Surgery : Procedures that are done purely for appearance are not covered.
Acupuncture : Medicare only covers acupuncture for chronic lower back pain and nothing else.
Most Care Outside the U.S. : Medicare usually does not cover healthcare you get outside the United States, except in very limited situations. If you need any of these services, you will need to pay out of pocket or get additional insurance that covers them.
Understanding Medicare Costs and Terminology
Medicare has its own language with terms you need to know. Here is what the most common words mean:
Premium : This is the amount you pay each month for your insurance coverage, even if you don’t use any medical services.
Deductible : This is the amount you pay for healthcare services before your insurance starts paying. You pay 100% of costs until you meet the deductible.
Coinsurance : After you meet your deductible, coinsurance is the percentage of costs you pay. Medicare Part B has 20% coinsurance for most services.
Copayment : This is a fixed dollar amount you pay for a service. For example, you might pay a $10 copayment for each doctor visit.
Out-of-Pocket Maximum : This is the most you will pay in a year. After you reach this amount, your plan pays 100% of covered services. Original Medicare does not have an out-of-pocket maximum, but Medicare Advantage plans do.
Formulary : This is the list of prescription drugs a Part D plan covers. Different plans have different formularies.
Prior Authorization : Some plans require you to get approval before receiving certain services or medications.
Network : These are the doctors, hospitals, and other providers that have an agreement with your insurance plan. Using in-network providers usually costs less.
Medicare Coverage Database and Resources
If you are not sure whether Medicare covers something specific, you have several ways to find out:
Ask Your Doctor : Your doctor’s office deals with Medicare all the time and can usually tell you if a service is covered.
Search Online : Medicare has a coverage database on their website at Medicare.gov. You can search for specific items or services to see if they are covered.
Call Medicare : You can call 1-800-MEDICARE (1-800-633-4227) to speak with someone who can answer your questions. TTY users can call 1-877-486-2048. They are available 24 hours a day, 7 days a week.
State Health Insurance Assistance Program (SHIP) : Every state has a SHIP that provides free Medicare counseling. They can help you understand your options and make decisions about coverage.
Don’t be afraid to ask questions. It is better to get clear answers before you enroll than to find out later that something you need is not covered.
Tips for Managing Your Medicare Coverage
Once you have Medicare, here are some tips to get the most out of your coverage:
Review Your Coverage Every Year : Your health needs can change, and plan benefits and costs change every year. During the Annual Enrollment Period (October 15 to December 7), review your current coverage and see if a different plan might work better.
Keep Good Records : Save all your medical bills, explanation of benefits statements, and receipts. This helps you track your spending and can be useful if you need to dispute a bill.
Use Preventive Services : Medicare covers many preventive services at no cost to you. Take advantage of annual wellness visits, cancer screenings, and other preventive care to catch health problems early.
Ask About Generic Drugs : Generic medications cost much less than brand-name drugs but work the same way. Ask your doctor if generic versions of your medications are available.
Understand Your Rights : You have the right to appeal if Medicare denies coverage for something. You also have the right to see any doctor who accepts Medicare if you have Original Medicare.
Watch Out for Fraud : Never give your Medicare number to someone who calls you or comes to your door. Medicare will never call you and ask for your number. Report suspected fraud to 1-800-MEDICARE.
How Medicare Billing Works for Healthcare Providers
Understanding how healthcare providers bill Medicare can help you make sense of your medical bills and avoid surprises.
The Medicare Billing Process
When you receive medical care, here is what happens behind the scenes:
Step 1 – Service Provided : You see your doctor or receive medical care. The provider’s office records all the services you received.
Step 2 – Claim Submitted : The healthcare provider submits a claim to Medicare. This claim includes codes that describe your diagnosis and the services provided.
Step 3 – Medicare Reviews the Claim : Medicare checks if the services are covered, if the provider followed proper procedures, and if the claim is coded correctly.
Step 4 – Medicare Pays Their Share : If approved, Medicare pays the provider their portion of the bill (usually 80% for Part B services after you meet your deductible).
Step 5 – You Get Billed : The provider bills you for any remaining amount, such as your deductible, coinsurance, or copayment.
You should receive a Medicare Summary Notice (MSN) every three months. This document shows all the services Medicare was billed for and what they paid. Review this carefully to catch any errors.
Understanding Medicare Claim Codes
Medical billing uses standard codes to describe services:
CPT Codes : These are Current Procedural Terminology codes that describe medical procedures and services. For example, a routine office visit might be coded as 99213.
ICD Codes : These are International Classification of Diseases codes that describe your diagnosis or health condition. For example, Type 2 diabetes is coded as E11.
HCPCS Codes : These are Healthcare Common Procedure Coding System codes used for equipment, supplies, and services not covered by CPT codes.
You don’t need to memorize these codes, but understanding that they exist helps you make sense of your medical bills and explanation of benefits.
What to Do If Medicare Denies a Claim
Sometimes Medicare denies coverage for a service or item. This can happen for several reasons:
- The service is not medically needed
- The service is not covered by Medicare
- The claim was coded incorrectly
- Required documentation is missing
If Medicare denies a claim, you have the right to appeal. The denial notice will explain why the claim was denied and how to file an appeal. Many denials are overturned on appeal, especially if the denial was due to a coding error or missing paperwork.
Your doctor’s office can help you with the appeal process. They may need to provide additional documentation showing that the service was medically needed.
Common Medicare Billing Mistakes to Avoid
Mistakes in medical billing happen more often than you might think. Here are some common errors and how to avoid them:
Duplicate Billing : Sometimes the same service gets billed twice by accident. Always check your Medicare Summary Notice to make sure you only paid for services once.
Upcoding : This happens when a provider bills for a more expensive service than what was actually provided. For example, billing for a comprehensive exam when you only had a basic checkup.
Services Not Received : Occasionally you might be billed for services you never received. This could be a simple error or, in rare cases, fraud.
Wrong Information : Billing errors can occur if your personal information is incorrect, such as your name, Medicare number, or date of birth.
To protect yourself, keep detailed records of all medical appointments and services. Compare your own records with the Medicare Summary Notice and medical bills. If you spot an error, contact the provider’s billing department right away.
Medicare Billing Rights and Protections
As a Medicare beneficiary, you have important rights when it comes to medical billing:
Right to Itemized Bills : You can request an itemized bill that shows exactly what services you were charged for and how much each service cost.
Right to Appeal : If Medicare denies coverage or you disagree with the amount they paid, you have the right to appeal the decision.
Right to Privacy : Your medical information is protected by law. Providers must keep your health information private and secure.
Right to Quality Care : You have the right to receive quality healthcare and to be treated with respect by healthcare providers.
Protection from Balance Billing : If your doctor accepts Medicare assignment (which most do), they cannot charge you more than the Medicare-approved amount. They can only bill you for your deductible, coinsurance, and any non-covered services.
If you feel your rights have been violated, you can file a complaint with Medicare or contact your State Health Insurance Assistance Program for help.
Understanding Medicare takes time, but it gets easier once you learn the basics. The most important thing is to make sure you have the coverage you need for your health and your budget. Take your time, ask questions, and don’t hesitate to get help from Medicare counselors or trusted healthcare providers.
Remember that you can change your Medicare coverage during certain times of the year, so if something is not working for you, you have options to make it better. Medicare is there to help you get the healthcare you need as you get older, and knowing how it works puts you in control of your health and your finances.
How Healthcare Providers Can Join Medicare Network
If you are a doctor, nurse, therapist, or other healthcare provider, you might want to join the Medicare network so you can treat Medicare patients. This process is called getting your Medicare enrollment or becoming a Medicare provider.
To join Medicare as a provider, you need to apply through the CMS (Centers for Medicare & Medicaid Services). You can apply online using the PECOS system, which stands for Provider Enrollment, Chain, and Ownership System. You will need your National Provider Identifier (NPI) number, which is like a special ID number for healthcare providers. If you don’t have an NPI yet, you must get one first from the National Plan and Provider Enumeration System website.
During the application, you will provide information about your practice, your medical license, where you went to school, and your work history. Medicare will check your background to make sure you are qualified and have not had problems with fraud or patient safety. This background check can take 30 to 90 days or sometimes longer.
Once Medicare approves you, you will get a Medicare provider number. This number is what you use when you bill Medicare for services you provide to patients. You also need to decide if you will accept Medicare assignment. If you accept assignment, you agree to accept the Medicare-approved amount as full payment. Most providers accept assignment because it makes billing easier and patients prefer doctors who accept assignment.
After you are enrolled, you must follow Medicare rules about documentation, coding, and billing. You need to keep good records of patient visits and use the correct medical codes when you submit claims. Medicare audits providers regularly to make sure they are following the rules. If you make mistakes or bill for services incorrectly, you could face penalties or lose your Medicare privileges.
Being in the Medicare network means you can treat millions of patients who have Medicare coverage. For many medical practices, Medicare patients make up a large portion of their business. The payment rates from Medicare are set by the government and are usually lower than private insurance, but the steady patient volume makes it worthwhile for most providers.
