Original Medicare (Part A and Part B) is the federal health insurance program primarily for individuals age 65 and older, as well as certain younger people with qualifying disabilities.
It consists of Part A, which helps cover inpatient hospital care, skilled nursing facility care, hospice, and some home health services, and Part B, which helps cover doctor visits, outpatient care, preventive services, and medically necessary treatments.
While Original Medicare provides broad access to healthcare providers nationwide who accept Medicare, it does not cover every healthcare expense.
Initial Enrollment Period (IEP)
Lasts 7 months—begins 3 months before your 65th birthday month, includes your birthday month, and ends 3 months after. If your birthday falls on the 1st of the month, Medicare considers you to reach age 65 the month before, so your IEP begins 4 months before your birthday month and ends 2 months after your birthday month.
General Enrollment Period (GEP)
January 1 – March 31 each year for those who missed their Initial Enrollment Period and don’t qualify for a Special Enrollment Period. Coverage begins the month after enrollment.
Special Enrollment Periods (SEP)
Available year-round for individuals who qualify due to certain life events, such as losing employer coverage or moving outside their plan’s service area.
Late Enrollment Penalty
If you miss your initial enrollment window and lack qualifying “creditable” coverage (like an employer plan).
Part A Penalty:
- If you have to buy Part A, and you don’t buy it when you’re first eligible for Medicare, your monthly premium may go up 10%.
- You’ll have to pay the penalty for twice the number of years you didn’t sign up.
Part B Penalty:
- You’ll pay an extra 10% for each year you could have signed up for Part B, but didn’t.
- You may also pay a higher premium depending on your income.
Generally, you won’t have to pay a Part B penalty if you qualify for a Special Enrollment Period, or you enroll in a Medicare Savings Program.
Medicare Advantage (Part C) plans combine your Medicare Part A (Hospital Insurance) and Part B (Medical Insurance) into one comprehensive plan offered by private insurance companies approved by Medicare.
Many plans also include prescription drug coverage (Part D) and may provide additional benefits not covered by Original Medicare, such as routine dental, vision, hearing, fitness programs, and transportation services.
Plan costs, provider networks, and benefits vary by location, making it important to compare your options each year to find the coverage that fits your healthcare needs and budget.
Initial Enrollment Period (IEP)
Lasts 7 months—begins 3 months before your 65th birthday month, includes your birthday month, and ends 3 months after. If your birthday falls on the 1st of the month, Medicare considers you to reach age 65 the month before, so your IEP begins 4 months before your birthday month and ends 2 months after your birthday month.
Annual Enrollment Period (AEP)
October 15 – December 7 each year. Enroll in, switch, or leave a Medicare Advantage plan. Coverage begins January 1.
Medicare Advantage Open Enrollment Period (MA OEP)
January 1 – March 31 each year. If you’re already enrolled in a Medicare Advantage plan, you may switch to another Medicare Advantage plan or return to Original Medicare. If you return to Original Medicare, you may also enroll in a standalone Part D Prescription Drug Plan.
Medicare Supplement Insurance, also known as Medigap, is designed to help cover many of the out-of-pocket costs that Original Medicare doesn't pay, such as: deductibles, copayments, and coinsurance.
These plans are offered by private insurance companies and work alongside Original Medicare (Parts A and B) to help make healthcare expenses more predictable.
With a Medicare Supplement Insurance plan, you can enjoy the freedom to see any doctor or specialist nationwide who accepts Medicare without worrying about provider networks or referrals.
Medigap Open Enrollment Period
Begins the first month you’re age 65 or older and enrolled in Medicare Part B and lasts 6 months. If your birthday is on the 1st of the month and your Medicare eligibility begins the month before, your Medigap Open Enrollment Period may also begin one month earlier, provided you’re enrolled in Part B. During this period, you generally have guaranteed issue rights and cannot be denied coverage based on health.
Prescription Drug Coverage (Medicare Part D) helps cover the cost of prescription medications and is available through private insurance companies approved by Medicare. It is designed to help reduce out-of-pocket costs for both brand-name and generic prescription drugs.
Part D plans are available as standalone Prescription Drug Plans (PDPs) for individuals with Original Medicare or may be included as part of many Medicare Advantage (Part C) plans.
Each Part D plan has its own list of covered medications (called a formulary), pharmacy network, monthly premium, deductible, and copayments or coinsurance. Because plans vary, it’s important to compare your prescription needs each year to ensure you’re enrolled in the plan that offers the best value.
Initial Enrollment Period (IEP)
Lasts 7 months—begins 3 months before your 65th birthday month, includes your birthday month, and ends 3 months after. If your birthday falls on the 1st of the month, Medicare considers you to reach age 65 the month before, so your IEP begins 4 months before your birthday month and ends 2 months after your birthday month.
Annual Enrollment Period (AEP)
October 15 – December 7 each year. Enroll in a Part D plan, switch to a different Part D plan, or drop your prescription drug coverage. Coverage begins January 1.