AEP (Annual Election Period)
The window from October 15 to December 7 each year when you can join, switch, or drop Medicare Advantage and Part D plans. Changes take effect January 1.
Assignment
An agreement by a doctor or provider to accept the Medicare-approved amount as full payment for a service.
Benefit period
Starts when you enter a hospital and ends after 60 consecutive days without inpatient care. The Part A deductible applies to each benefit period.
CMS
Centers for Medicare & Medicaid Services. The federal agency that runs Medicare and oversees Medicaid.
Coinsurance
Your share of costs after you've paid your deductible. For Part B, this is typically 20% of the Medicare-approved amount.
Copayment (copay)
A fixed dollar amount you pay for a covered service, such as $20 for a doctor visit.
Creditable coverage
Health insurance coverage that is at least as good as Medicare's standard coverage. Employer plans with 20+ employees are typically creditable.
Deductible
The amount you pay out of pocket before your insurance begins to pay. Part B has an annual deductible of $257 in 2026.
Dual eligible
Someone who qualifies for both Medicare and Medicaid. In Colorado, this means having both Medicare and Health First Colorado.
Durable Medical Equipment (DME)
Medically necessary equipment for home use, such as wheelchairs, walkers, hospital beds, and oxygen equipment.
Extra Help (LIS)
A Medicare program that helps people with limited income and resources pay for Part D prescription drug costs. Also called the Low-Income Subsidy.
Formulary
A list of prescription drugs covered by a Part D or Medicare Advantage plan. Drugs are organized into tiers with different costs.
Guaranteed issue rights
Rights that allow you to buy a Medigap policy without medical underwriting. Available during your Medigap open enrollment and in certain other situations.
Health First Colorado
Colorado's Medicaid program, providing health coverage to eligible low-income residents.
IEP (Initial Enrollment Period)
Your first chance to sign up for Medicare — a 7-month window around your 65th birthday (3 months before, your birthday month, and 3 months after).
IRMAA
Income-Related Monthly Adjustment Amount. An additional charge for Part B and Part D premiums for higher-income beneficiaries.
Medicaid
A joint federal-state program providing health coverage to low-income individuals. In Colorado, it's called Health First Colorado.
Medicare Advantage (Part C)
A type of Medicare plan offered by private insurers that bundles Parts A, B, and usually D. Often includes extra benefits like dental and vision.
Medicare Supplement
See Medigap.
Medigap
Supplemental insurance sold by private companies to help pay out-of-pocket costs not covered by Original Medicare. Standardized by letter (A, B, G, N, etc.).
Network
The doctors, hospitals, and other providers that have contracted with a Medicare Advantage plan to provide care at negotiated rates.
OEP (Open Enrollment Period)
January 1 through March 31 each year. If you have a Medicare Advantage plan, you can switch plans or return to Original Medicare.
Original Medicare
The traditional Medicare program (Parts A and B) administered directly by the federal government. Covers hospital and medical services.
Part A
Hospital insurance. Covers inpatient hospital stays, skilled nursing facilities, hospice, and some home health care.
Part B
Medical insurance. Covers doctor visits, outpatient care, preventive services, and durable medical equipment.
Part C
See Medicare Advantage.
Part D
Prescription drug coverage offered through private insurance plans approved by Medicare.
SEP (Special Enrollment Period)
A time outside regular enrollment periods when you can sign up for or change Medicare coverage due to specific life events.
SHIP
State Health Insurance Assistance Program. In Colorado, SHIP provides free Medicare counseling. Call 1-888-696-7213.
SNP (Special Needs Plan)
A type of Medicare Advantage plan for people with specific conditions, limited income, or dual eligibility.
Step therapy
A Part D requirement to try a less expensive drug before the plan covers a more expensive alternative.