Everything You Need to Understand Medicare Before You Choose a Plan
Medicare can feel confusing because it connects to Social Security, employer coverage, Medicaid, Medi-Cal in California, VA benefits, TRICARE, prescription drugs, dental, vision, doctors, hospitals, and enrollment deadlines.
Before choosing any plan, know these 5 things:
- Whether you have Part A and Part B
- Whether your doctors accept the plan
- Whether your prescriptions are covered
- Whether you qualify for Medi-Cal, Medicaid, Extra Help, or a Medicare Savings Program
- Whether employer, VA, TRICARE, or retiree coverage changes your decision
Medicare Guide Menu
1. What Medicare Is 2. Parts A, B, C, D, and Medigap 3. Original Medicare vs Medicare Advantage 4. Medicare Costs 5. Enrollment Periods and Penalties 6. Prescription Drug Coverage 7. Medicaid, Medi-Cal, Dual Eligibility, and D-SNPs 8. Medicare While Still Working 9. Medicare With VA, Veterans Benefits, and TRICARE 10. Special Situations 11. Medicare Decision Checklist 12. FAQWhat Is Medicare?
Medicare is federal health insurance mainly for people age 65 or older. Some people under 65 may qualify because of disability, End-Stage Renal Disease, or ALS. Medicare is individual coverage. It is not a family plan, and spouses may choose different coverage options.
Most People Start at 65
Your first Medicare enrollment window usually begins 3 months before the month you turn 65 and ends 3 months after your birthday month.
Same Medicare Foundation Nationwide
Original Medicare is federal. Medicare Advantage, Part D, and Medigap plans are offered by private companies and vary by area.
No Family Plans
You and your spouse do not have to pick the same Medicare coverage. Each person should review doctors, drugs, budget, and health needs.
The Parts of Medicare Explained
Hospital Insurance
Helps cover inpatient hospital care, skilled nursing facility care, hospice, and some home health care.
Medical Insurance
Helps cover doctor visits, outpatient care, preventive services, durable medical equipment, lab work, and other medically necessary services.
Medicare Advantage
An alternative way to receive Medicare through a private plan. It includes Part A and Part B, and usually includes Part D.
Drug Coverage
Helps cover prescription drugs. You can get it through a stand-alone Part D plan or many Medicare Advantage plans.
Original Medicare vs Medicare Advantage
| Topic | Original Medicare | Medicare Advantage |
|---|---|---|
| How it works | Federal Medicare pays providers directly for covered services. | You receive Medicare benefits through a private Medicare-approved plan. |
| Includes | Part A and Part B. You may add Part D and Medigap separately. | Part A and Part B. Most plans include Part D. |
| Doctor access | You can generally use any doctor or hospital in the U.S. that accepts Medicare. | You may need to use a network, especially with HMO plans. |
| Out-of-pocket limit | No built-in yearly maximum unless you have other coverage like Medigap or Medicaid. | Plans have an annual maximum out-of-pocket limit for covered Part A and B services. |
| Extra benefits | Usually does not include dental, vision, hearing, transportation, OTC, or fitness benefits. | Many plans may include extra benefits such as dental, vision, hearing, OTC, transportation, and fitness. |
| Medigap | You may be able to buy a Medigap plan. | You cannot use Medigap to pay Medicare Advantage plan costs. |
Medicare Costs to Understand
Medicare costs can include premiums, deductibles, copays, coinsurance, drug costs, and possible late enrollment penalties.
Premium
The monthly amount you pay to have coverage. Most people pay no Part A premium, but most people pay a Part B premium.
Deductible
The amount you pay before coverage begins paying for certain services.
Copay / Coinsurance
Your share of the cost when you receive care, fill prescriptions, or use services.
2026 Standard Medicare Cost Examples
| Medicare Cost | 2026 Amount | Plain-English Explanation |
|---|---|---|
| Part B Standard Premium | $202.90/month | Most people with Part B pay this monthly amount unless they qualify for help or pay more because of income. |
| Part B Deductible | $283/year | You generally pay this before Medicare starts sharing certain Part B costs. |
| Part A Inpatient Hospital Deductible | $1,736 per benefit period | This applies when admitted as an inpatient hospital patient under Part A. |
| Part A Premium | $0 for most people | Most people qualify for premium-free Part A because they or a spouse paid Medicare taxes long enough. |
Medicare Enrollment Periods
Initial Enrollment Period
Your first chance to sign up. It lasts 7 months: 3 months before your 65th birthday month, your birthday month, and 3 months after.
Annual Open Enrollment
October 15 through December 7. You can change Medicare Advantage or Part D coverage for January 1.
Medicare Advantage Open Enrollment
January 1 through March 31. People already in a Medicare Advantage plan may switch MA plans or return to Original Medicare.
Special Enrollment Period
Available in certain life events, such as losing employer coverage, moving, qualifying for Medicaid/Medi-Cal, or losing Extra Help.
General Enrollment Period
January 1 through March 31 for people who missed signing up for Part A or Part B and do not qualify for a Special Enrollment Period.
Medigap Open Enrollment
A 6-month window that starts when you are 65 or older and enrolled in Part B. This is usually the best time to buy Medigap.
Prescription Drug Coverage
Prescription drug coverage is usually handled through Medicare Part D. You can get Part D through a stand-alone drug plan with Original Medicare or through many Medicare Advantage plans that include drug coverage.
Formulary
The list of covered drugs. Every plan has its own formulary, and it can change each year.
Drug Tiers
Plans group drugs into tiers. Lower tiers usually cost less, while higher tiers may cost more.
Pharmacy Network
Costs can change depending on whether the pharmacy is preferred, standard, or out-of-network.
Prior Authorization
The plan may require approval before covering certain medications.
Step Therapy
The plan may require trying a lower-cost drug first before covering another medication.
Quantity Limits
The plan may limit how much medication you can receive at one time.
Medicaid, Medi-Cal, Dual Eligibility, and D-SNPs
Medicaid is the state and federal health program for people with limited income and resources. In California, Medicaid is called Medi-Cal. Someone who has both Medicare and Medicaid/Medi-Cal is often called “dual eligible.”
Medicare + Medicaid
Medicare usually pays first for Medicare-covered services. Medicaid may help with premiums, copays, coinsurance, deductibles, and services Medicare does not fully cover.
Medicare + Medi-Cal in California
In California, people with both programs may be called “Medi-Medi.” Full-scope Medi-Cal may help cover Medicare cost sharing and additional benefits.
D-SNP Plans
Dual Eligible Special Needs Plans are Medicare Advantage plans designed for people with both Medicare and Medicaid/Medi-Cal.
Medi-Medi Plans
In California, Medi-Medi Plans coordinate Medicare and Medi-Cal benefits through one plan structure in participating counties.
Common Help Programs
| Program | What It May Help With |
|---|---|
| Medicaid / Medi-Cal | Medical costs, Medicare cost sharing, long-term services, personal care, and other state-based benefits. |
| Medicare Savings Program | May help pay Part B premium and sometimes deductibles, copays, and coinsurance depending on eligibility level. |
| Extra Help | Helps people with limited income and resources pay Medicare Part D drug costs. |
| D-SNP | A Medicare Advantage plan designed to coordinate benefits for people with Medicare and Medicaid/Medi-Cal. |
Medicare If You Are Still Working
Medicare decisions are different if you or your spouse still has employer group health coverage. Do not assume you can delay Medicare safely without checking.
Large Employer Coverage
If you or your spouse are actively working and covered by a qualifying employer group health plan, you may be able to delay Part B without penalty.
Small Employer Coverage
Some smaller employer plans may require Medicare to pay first once you are eligible. Ask HR or the benefits administrator before delaying Part B.
COBRA
COBRA is not the same as active employer coverage. COBRA usually does not protect you from Part B penalties if you delay Medicare after employment ends.
HSA Warning
If you contribute to an HSA, Medicare enrollment can affect contribution eligibility. Many people need to stop HSA contributions before Medicare starts.
Medicare With VA Benefits, Veterans Benefits, and TRICARE
Medicare and VA Benefits
VA benefits and Medicare do not usually pay for the same service at the same time. You generally choose which benefit you are using when you receive care.
VA coverage may work best inside VA-authorized care. Medicare may help when you use Medicare-approved providers outside the VA system.
Medicare and TRICARE
Many people with TRICARE who become Medicare-eligible need both Part A and Part B to keep TRICARE For Life. If not on active duty, Medicare generally pays first and TRICARE may pay second.
If you have TRICARE drug coverage, you may not need a Medicare Part D plan.
Special Situations Connected to Medicare
Retiree Coverage
Some retiree plans require you to enroll in Part A and Part B. Joining a non-employer Medicare plan may affect retiree benefits.
Marketplace Coverage
Once eligible for Medicare, Marketplace subsidies may be affected. Review before keeping Marketplace coverage after Medicare eligibility.
Disability
Some people qualify for Medicare before age 65 after receiving disability benefits for a required period or due to certain conditions.
ESRD
People with End-Stage Renal Disease may qualify for Medicare under special rules. Coordination with other coverage can be different.
Moving
Moving to a new county, state, or service area can trigger a Special Enrollment Period for Medicare Advantage or Part D.
Low Income Help
Extra Help, Medicaid/Medi-Cal, and Medicare Savings Programs can reduce costs for eligible beneficiaries.
Medicare Decision Checklist
- Confirm whether you have Medicare Part A and Part B.
- Check if you are still working or covered through a spouse’s employer.
- Ask whether your employer coverage is creditable and whether Medicare should be primary or secondary.
- List every doctor, specialist, hospital, and medical group you want to keep.
- List every prescription, dosage, frequency, and preferred pharmacy.
- Decide whether you prefer Original Medicare with possible Medigap or a Medicare Advantage plan.
- Check if you qualify for Medicaid, Medi-Cal, Extra Help, or Medicare Savings Programs.
- Review dental, vision, hearing, transportation, OTC, and fitness needs.
- Compare premiums, copays, deductibles, maximum out-of-pocket, and drug costs.
- Review plan ratings, network rules, referrals, and prior authorization requirements.
- Do not cancel employer, VA, TRICARE, retiree, or union coverage without understanding the impact.
Frequently Asked Medicare Questions
Do I have to enroll in Medicare at 65?
Not always. If you or your spouse are actively working and you have qualifying employer group health coverage, you may be able to delay Part B. If you do not have qualifying coverage, delaying may cause penalties or gaps.
Can I have Medicare and employer insurance at the same time?
Yes. One plan usually pays first and the other pays second. Which one pays first depends on employer size, active employment, disability, ESRD, and the type of coverage.
Can I have Medicare and Medicaid?
Yes. People with both are called dual eligible. In California, Medicaid is called Medi-Cal, and people with both Medicare and Medi-Cal may be called Medi-Medi.
Can I have Medicare and VA benefits?
Yes. However, Medicare and VA generally do not pay for the same service at the same time. You usually choose which benefit you are using when receiving care.
Do I need Part B if I have TRICARE?
Many people with TRICARE who are entitled to premium-free Part A need Part B to keep TRICARE For Life. Always confirm with TRICARE before delaying Part B.
What is the difference between Medicare Advantage and Medigap?
Medicare Advantage is an alternative way to receive Medicare benefits through a private plan. Medigap is supplemental insurance used with Original Medicare to help pay certain out-of-pocket costs.
Can I have Medicare Advantage and Medigap together?
No. Medigap does not work with Medicare Advantage and cannot be used to pay Medicare Advantage copays or deductibles.
Do Medicare Advantage plans include prescription drugs?
Many do, but not all. Medicare Advantage plans that include drug coverage are often called MAPD plans. Always check your medications before enrolling.
What happens if I miss Part D?
If you go too long without creditable drug coverage, you may owe a Part D late enrollment penalty when you enroll later.
What should I review every year?
Doctors, hospitals, prescriptions, pharmacy, premiums, copays, maximum out-of-pocket, dental, vision, hearing, transportation, OTC, and any plan notices of change.
Need Help Choosing the Right Medicare Option?
A licensed Medicare professional can help you compare your options, check your doctors, review prescriptions, look for financial assistance programs, and explain how Medicare works with employer, Medi-Cal, Medicaid, VA, or TRICARE coverage.