Glossary

Insurance Terms, Explained Simply

Plain-English definitions of the terms that come up most often — no jargon, no fine print.

Medicare Basics Enrollment Medicare Parts Medicare Advantage Medigap Prescription Drugs Healthcare Providers Insurance Costs Government Assistance Claims & Billing Provider Networks Insurance Terms Acronyms Advanced Medicare Topics

10 terms

Medicare Basics

BeneficiaryBeginner: The person or entity designated to receive the benefit from an insurance policy — most commonly the death benefit from a life insurance policy, but the term also applies broadly to anyone covered under a plan, like a "Medicare beneficiary." Keeping beneficiary designations up to date after major life events, like marriage or divorce, is worth revisiting periodically.Related terms:Medicare Beneficiary Identifier (MBI)Policyholder Original Medicare
Benefit PeriodAdvanced: A way some insurance measures your use of certain services, most commonly seen in Medicare Part A hospital coverage. It starts the day you're admitted as an inpatient and ends after you've been out of the hospital or skilled nursing facility for 60 days in a row, and a new benefit period (with its own deductible) can start if you're readmitted after that.Related terms:Medicare Part A Part A Deductible Skilled Nursing Facility (SNF)Lifetime Reserve Days
Dual EligibleIntermediate: A person who qualifies for both Medicare and Medicaid at the same time, with Medicaid typically helping pay Medicare premiums and cost sharing. Dual eligibles can often join special Medicare Advantage plans (D-SNPs) designed to coordinate both programs.Related terms:Medicaid D-SNP (Dual Eligible Special Needs Plan)Medicare Savings Programs (MSPs)QMB (Qualified Medicare Beneficiary)
Medically NecessaryIntermediate: Services or supplies that are needed to diagnose or treat an illness, injury, or condition and that meet accepted standards of medicine — the basic test insurance uses to decide whether something is covered. If a plan decides a service isn't medically necessary, you have the right to appeal.Related terms:Prior Authorization Appeal Advance Beneficiary Notice (ABN)Exclusions
Medicare & You HandbookBeginner: The official annual handbook CMS mails to every Medicare household each fall, summarizing benefits, costs, enrollment windows, and plan options for the coming year. It's the authoritative plain-language reference for what's changing in Medicare.Related terms:CMS (Centers for Medicare & Medicaid Services)Annual Enrollment Period (AEP)Annual Notice of Change (ANOC)
Medicare Beneficiary Identifier (MBI)Beginner: The unique 11-character number on your red, white, and blue Medicare card that identifies you in the Medicare system, which replaced Social Security–based numbers to protect against identity theft. Guard it like a credit card number — scammers actively target Medicare numbers.Related terms:Beneficiary Original Medicare Medicare Summary Notice (MSN)
Medicare Part ABeginner: Hospital insurance that helps cover inpatient hospital stays, skilled nursing facility care, hospice, and some home health care. Most people get Part A premium-free because they (or a spouse) paid Medicare taxes for at least 10 years.Related terms:Medicare Part B Original Medicare Benefit Period Part A Deductible Skilled Nursing Facility (SNF)
Medicare Part BBeginner: Medical insurance that helps cover doctor visits, outpatient care, preventive services, lab tests, and durable medical equipment. Part B charges a monthly premium set annually, and higher-income beneficiaries pay more through IRMAA.Related terms:Medicare Part A Original Medicare Part B Premium Part B Deductible IRMAA (Income-Related Monthly Adjustment Amount)
Medicare Summary Notice (MSN)Beginner: The statement Original Medicare mails every three months showing the services billed to Medicare, what Medicare paid, and what you may owe the provider. It is not a bill — but reviewing it helps you catch billing errors and potential fraud.Related terms:Explanation of Benefits (EOB)Claim Original Medicare
Original MedicareBeginner: The traditional, government-run version of Medicare made up of Part A (hospital insurance) and Part B (medical insurance), where you can see any provider in the U.S. that accepts Medicare. It doesn't include drug coverage or an out-of-pocket maximum, which is why many people add a Part D plan and a Medigap policy.Related terms:Medicare Part A Medicare Part B Medicare Supplement (Medigap)Medicare Part C (Medicare Advantage)Medicare Part D

12 terms

Enrollment

Annual Enrollment Period (AEP)Beginner: The October 15 – December 7 window each year when anyone with Medicare can join, switch, or drop a Medicare Advantage or Part D drug plan, with changes taking effect January 1. It's the main opportunity to review whether your plan still fits your doctors, drugs, and budget.Related terms:Medicare Advantage Open Enrollment Period (MA OEP)Annual Notice of Change (ANOC)Initial Enrollment Period (IEP)Special Enrollment Period
Automatic EnrollmentBeginner: When Medicare signs you up for Parts A and B without you applying — this happens if you're already receiving Social Security benefits at least 4 months before turning 65, or after 24 months of Social Security disability benefits. Everyone else must actively apply through Social Security.Related terms:Initial Enrollment Period (IEP)SSA (Social Security Administration)Medicare Part A Medicare Part B
Creditable CoverageIntermediate: Health or drug coverage considered at least as good as what Medicare provides — for example, an employer plan or TRICARE — meaning you can delay enrolling in Medicare Part B or Part D without facing a late enrollment penalty later. Whether a specific plan counts as creditable is usually stated in a notice your plan sends you each year.Related terms:Late Enrollment Penalty Medicare Part D COBRA Initial Enrollment Period (IEP)
DisenrollmentIntermediate: The process of leaving a Medicare Advantage or Part D plan — either by switching to another plan during a valid enrollment window, returning to Original Medicare, or being removed for reasons like moving out of the service area or nonpayment. Timing rules control when you can voluntarily disenroll.Related terms:Medicare Advantage Open Enrollment Period (MA OEP)Annual Enrollment Period (AEP)Service Area Grace Period
Effective DateBeginner: The date your insurance coverage actually begins — which is often later than the day you enroll. Knowing your effective date matters for avoiding gaps between an old plan ending and a new one starting.Related terms:Qualifying Life Event General Enrollment Period (GEP)Grace Period
General Enrollment Period (GEP)Intermediate: The January 1 – March 31 window when you can sign up for Medicare Part A and/or Part B if you missed your Initial Enrollment Period and don't qualify for a Special Enrollment Period, with coverage starting the month after you enroll. Late enrollment penalties may apply.Related terms:Initial Enrollment Period (IEP)Late Enrollment Penalty Special Enrollment Period Effective Date
Initial Enrollment Period (IEP)Beginner: Your first chance to sign up for Medicare: a 7-month window that starts 3 months before the month you turn 65, includes your birthday month, and ends 3 months after. Missing it can mean late enrollment penalties and gaps in coverage unless you have creditable coverage.Related terms:Annual Enrollment Period (AEP)General Enrollment Period (GEP)Late Enrollment Penalty Creditable Coverage
Late Enrollment PenaltyIntermediate: An extra amount added to your Medicare premium — usually for life — if you sign up for Part B or Part D after your initial window without having creditable coverage in between. The Part B penalty grows 10% for each full 12-month period you delayed; the Part D penalty accrues monthly.Related terms:Creditable Coverage Initial Enrollment Period (IEP)General Enrollment Period (GEP)Part B Premium
Medicare Advantage Open Enrollment Period (MA OEP)Intermediate: A January 1 – March 31 window when people already enrolled in a Medicare Advantage plan can switch to a different Medicare Advantage plan or return to Original Medicare (and add a Part D plan) one time. You can't use it to jump from Original Medicare into Medicare Advantage.Related terms:Annual Enrollment Period (AEP)Medicare Part C (Medicare Advantage)Disenrollment Original Medicare
Open Enrollment (ACA Marketplace)Beginner: The annual window — generally November 1 through January 15 in most states — when anyone can enroll in or change ACA Marketplace health insurance without needing a qualifying life event. Outside this window, you need a Special Enrollment Period to sign up.Related terms:Special Enrollment Period Qualifying Life Event ACA (Affordable Care Act)Metal Tiers (Bronze, Silver, Gold, Platinum)
Qualifying Life EventBeginner: A major life change — like losing job-based coverage, getting married, having a baby, turning 26, or moving to a new coverage area — that unlocks a Special Enrollment Period to sign up for or change health insurance outside the normal windows. Most events give you a 60-day window to act.Related terms:Special Enrollment Period Open Enrollment (ACA Marketplace)COBRA Effective Date
Special Enrollment PeriodIntermediate: A window outside the normal annual enrollment times when you're allowed to sign up for or change insurance coverage, triggered by a specific qualifying event like losing other coverage, moving, or a change in household. The exact triggers, length of the window, and rules differ depending on whether you're talking about Medicare, ACA Marketplace, or employer coverage.Related terms:Qualifying Life Event Annual Enrollment Period (AEP)Open Enrollment (ACA Marketplace)Initial Enrollment Period (IEP)

6 terms

Medicare Parts

IRMAA (Income-Related Monthly Adjustment Amount)Advanced: A surcharge added to your Part B and Part D premiums if your income from two years ago exceeds set thresholds — the higher your income bracket, the bigger the surcharge. You can appeal IRMAA if a life-changing event like retirement has since lowered your income.Related terms:Part B Premium MAGI (Modified Adjusted Gross Income)Appeal SSA (Social Security Administration)
Medicare Part C (Medicare Advantage)Beginner: The part of Medicare that lets private insurance companies bundle your Part A, Part B, and usually Part D coverage into one plan, often with extras like dental or vision, in exchange for using the plan's provider network and rules. You must still be enrolled in Parts A and B to join.Related terms:MAPD (Medicare Advantage Prescription Drug Plan)Original Medicare Maximum Out-of-Pocket (MOOP)Special Needs Plan (SNP)Star Ratings
Medicare Part DBeginner: Medicare's prescription drug benefit, offered through private stand-alone drug plans (PDPs) or built into Medicare Advantage plans (MAPDs). Each plan has its own formulary, pharmacy network, and costs, and federal law now caps your annual out-of-pocket drug spending.Related terms:PDP (Stand-Alone Prescription Drug Plan)Formulary Part D Out-of-Pocket Cap Late Enrollment Penalty Extra Help (Low-Income Subsidy / LIS)
Part A DeductibleIntermediate: The amount you pay when admitted to the hospital as an inpatient before Medicare Part A starts covering costs — charged per benefit period, not per year, so you could pay it more than once in the same year. Medigap plans typically cover some or all of it.Related terms:Medicare Part A Benefit Period Deductible Medicare Supplement (Medigap)
Part B DeductibleBeginner: The annual amount you pay for Part B–covered services (like doctor visits and outpatient care) before Medicare begins paying its 80% share. It resets each calendar year and is set annually by CMS.Related terms:Medicare Part B Deductible Coinsurance Medigap Plan G
Part B PremiumBeginner: The monthly amount most people pay for Medicare Part B, set by CMS each year and usually deducted directly from your Social Security check. Higher-income beneficiaries pay more through IRMAA surcharges.Related terms:Medicare Part B IRMAA (Income-Related Monthly Adjustment Amount)Premium Medicare Savings Programs (MSPs)

7 terms

Medicare Advantage

D-SNP (Dual Eligible Special Needs Plan)Advanced: A Medicare Advantage plan exclusively for people who have both Medicare and Medicaid, designed to coordinate the two programs' benefits and often including extra help with things like dental, transportation, or over-the-counter allowances. Many dual eligibles can switch D-SNPs outside normal enrollment windows.Related terms:Special Needs Plan (SNP)Dual Eligible Medicaid Supplemental Benefits
MAPD (Medicare Advantage Prescription Drug Plan)Intermediate: A Medicare Advantage plan that includes Part D drug coverage in the same package — the most common type of Medicare Advantage plan. If you join an MAPD, you get medical and drug coverage under one card, one premium, and one set of rules.Related terms:Medicare Part C (Medicare Advantage)PDP (Stand-Alone Prescription Drug Plan)Formulary Maximum Out-of-Pocket (MOOP)
Maximum Out-of-Pocket (MOOP)Intermediate: The yearly cap on what you can spend on covered medical services in a Medicare Advantage plan — a protection Original Medicare alone doesn't offer. Once you reach the MOOP, the plan pays 100% of covered medical costs for the rest of the year (drug costs are capped separately under Part D).Related terms:Out-of-Pocket Maximum Medicare Part C (Medicare Advantage)Part D Out-of-Pocket Cap Cost Sharing
Service AreaIntermediate: The geographic region — usually specific counties — where a Medicare Advantage or Part D plan is offered and where you must live to enroll and stay enrolled. Moving out of your plan's service area triggers a Special Enrollment Period to pick new coverage.Related terms:Medicare Part C (Medicare Advantage)Special Enrollment Period Disenrollment Network
Special Needs Plan (SNP)Intermediate: A type of Medicare Advantage plan designed for people with specific situations — chronic conditions (C-SNP), dual Medicare/Medicaid eligibility (D-SNP), or living in an institution (I-SNP) — with benefits, networks, and drug formularies tailored to that group. Enrollment is limited to people who meet the plan's qualifying criteria.Related terms:D-SNP (Dual Eligible Special Needs Plan)Medicare Part C (Medicare Advantage)Dual Eligible Medicaid
Star RatingsBeginner: Medicare's 1-to-5-star quality scores for Medicare Advantage and Part D plans, based on measures like preventive care, member complaints, and customer service. A 5-star plan can be joined almost any time of year through a special enrollment opportunity.Related terms:Medicare Part C (Medicare Advantage)CMS (Centers for Medicare & Medicaid Services)Annual Enrollment Period (AEP)PDP (Stand-Alone Prescription Drug Plan)
Supplemental BenefitsBeginner: Extra benefits many Medicare Advantage plans include beyond what Original Medicare covers — commonly dental, vision, hearing, fitness memberships, over-the-counter allowances, or transportation to appointments. Exactly what's included, and the limits, vary widely from plan to plan and year to year.Related terms:Medicare Part C (Medicare Advantage)MAPD (Medicare Advantage Prescription Drug Plan)Star Ratings Annual Notice of Change (ANOC)

8 terms

Medigap

Community Rating (Medigap Pricing)Advanced: One of three ways Medigap premiums are priced: community-rated plans charge everyone the same regardless of age, issue-age plans price by your age when you buy, and attained-age plans raise premiums as you get older. Knowing which method an insurer uses helps you predict how your premium will change over time.Related terms:Medicare Supplement (Medigap)Premium Underwriting
Guaranteed IssueIntermediate: A requirement that an insurer sell you a policy without denying coverage or charging more based on your health, regardless of pre-existing conditions. This concept shows up across different types of insurance under different rules — for example, all ACA Marketplace plans are guaranteed issue year-round, while Medigap is only guaranteed issue during specific windows or qualifying situations.Related terms:Medigap Open Enrollment Period Underwriting Medigap Birthday Rule Pre-Existing Condition
High-Deductible Plan GAdvanced: A version of Medigap Plan G with a much lower monthly premium in exchange for a yearly deductible (set annually by CMS) you must meet before the plan pays. It can suit people who want catastrophic protection and are comfortable covering routine cost sharing themselves.Related terms:Medigap Plan G Deductible Medicare Supplement (Medigap)Premium
Medicare Supplement (Medigap)Beginner: Private insurance that works alongside Original Medicare to pay some or all of your share of costs — deductibles, coinsurance, and copays — in exchange for a monthly premium. Plans are standardized by letter (like Plan G or Plan N), so benefits are identical across companies; only the price and service differ.Related terms:Medigap Plan G Medigap Plan N Medigap Open Enrollment Period Original Medicare Guaranteed Issue
Medigap Birthday RuleAdvanced: A rule in a handful of states that gives Medigap policyholders a yearly window around their birthday to switch to another Medigap plan with equal or lesser benefits without medical underwriting. Most states — including Wyoming and Utah — don't have a birthday rule, which makes your initial Medigap window especially important there.Related terms:Medigap Open Enrollment Period Underwriting Guaranteed Issue Medicare Supplement (Medigap)
Medigap Open Enrollment PeriodIntermediate: The one-time, 6-month window starting the month you're 65 or older and enrolled in Part B, during which you can buy any Medigap policy sold in your state without medical underwriting. Outside this window, insurers in most states can review your health and charge more or decline coverage.Related terms:Medicare Supplement (Medigap)Guaranteed Issue Underwriting Medicare Part B
Medigap Plan GIntermediate: The most comprehensive Medigap plan available to people new to Medicare, covering everything Original Medicare doesn't except the annual Part B deductible. After that deductible, Plan G leaves you with essentially no bills for Medicare-covered services.Related terms:Medigap Plan N High-Deductible Plan G Part B Deductible Medicare Supplement (Medigap)
Medigap Plan NIntermediate: A popular lower-premium Medigap option that covers most of your Medicare cost sharing but asks you to pay small copays for some office and ER visits, the annual Part B deductible, and any Part B excess charges. It trades slightly more cost sharing for a meaningfully lower monthly premium than Plan G.Related terms:Medigap Plan G Part B Excess Charges Medicare Supplement (Medigap)Copay

10 terms

Prescription Drugs

Brand-Name DrugBeginner: A medication sold under a trademarked name by the company that developed it, usually placed on higher formulary tiers with higher copays than generic equivalents. Some brand drugs have no generic version yet, which is where formulary exceptions and manufacturer programs can matter.Related terms:Generic Drug Drug Tier Formulary Exception
Drug TierBeginner: The cost level a plan assigns to each drug on its formulary — typically preferred generics on the cheapest tiers and specialty drugs on the most expensive. The tier, not the drug's retail price, usually determines your copay or coinsurance.Related terms:Formulary Generic Drug Brand-Name Drug Copay
FormularyIntermediate: The specific list of prescription drugs a health or drug plan covers, usually organized into cost tiers that determine your copay or coinsurance for each medication. Formularies vary by plan and can change from year to year.Related terms:Drug Tier PDP (Stand-Alone Prescription Drug Plan)Formulary Exception Step Therapy
Formulary ExceptionAdvanced: A formal request asking your drug plan to cover a medication that isn't on its formulary, or to relax a rule like step therapy or a quantity limit, backed by a statement from your doctor. Plans must respond within set timeframes, and you can appeal a denial.Related terms:Formulary Step Therapy Appeal Quantity Limits
Generic DrugBeginner: A medication with the same active ingredient, strength, and effect as a brand-name drug, sold at a much lower price after the brand's patent expires. Plans place generics on their cheapest tiers, and asking your doctor about generic options is one of the simplest ways to cut drug costs.Related terms:Brand-Name Drug Drug Tier Formulary
Part D Out-of-Pocket CapIntermediate: The annual federal limit (adjusted each year) on what you pay out of pocket for covered Part D drugs — once you reach it, you pay nothing more for covered prescriptions the rest of the year. This cap replaced the old 'donut hole' coverage gap structure.Related terms:Medicare Part D Donut Hole (Coverage Gap)Maximum Out-of-Pocket (MOOP)Extra Help (Low-Income Subsidy / LIS)
PDP (Stand-Alone Prescription Drug Plan)Intermediate: A private Part D plan that covers only prescription drugs, designed to pair with Original Medicare (and often a Medigap policy). Each PDP has its own premium, formulary, and pharmacy network, and comparing them annually often reveals meaningful savings.Related terms:Medicare Part D MAPD (Medicare Advantage Prescription Drug Plan)Formulary Preferred Pharmacy
Preferred PharmacyIntermediate: A pharmacy that has negotiated lower cost sharing with your drug plan — filling prescriptions there usually means lower copays than at standard in-network pharmacies. Checking whether your pharmacy is 'preferred' (not just 'in-network') can save hundreds per year.Related terms:PDP (Stand-Alone Prescription Drug Plan)Network Copay Formulary
Quantity LimitsIntermediate: A restriction on how much of a medication a plan will cover in a given period — for example, 30 tablets per month. Your doctor can request an exception if you medically need more than the limit allows.Related terms:Step Therapy Formulary Formulary Exception Prior Authorization
Step TherapyIntermediate: A plan rule requiring you to try a cheaper, proven medication first before the plan will cover a more expensive one for the same condition. If the first-step drug doesn't work for you, your doctor can request an exception.Related terms:Prior Authorization Formulary Exception Formulary Quantity Limits

8 terms

Healthcare Providers

Medicare AssignmentIntermediate: An agreement by a doctor or supplier to accept the Medicare-approved amount as full payment for covered services, so you only owe your normal deductible and coinsurance. Providers who don't accept assignment can charge up to 15% more — the Part B excess charge.Related terms:Part B Excess Charges Participating Provider Medicare Part B Balance Billing
Part B Excess ChargesAdvanced: The up-to-15% above the Medicare-approved amount that non-participating providers are allowed to bill you for Part B services. They're uncommon in practice, and some Medigap plans (like Plan G) cover them entirely while Plan N does not.Related terms:Medicare Assignment Medigap Plan G Medigap Plan N Balance Billing
Participating ProviderIntermediate: A doctor or facility that has agreed to always accept Medicare assignment (or a plan's contracted rates) for covered services. Seeing participating providers keeps your costs predictable and eliminates surprise excess charges.Related terms:Medicare Assignment Part B Excess Charges Network Provider Directory
Primary Care Physician (PCP)Beginner: The doctor who manages your overall health, handles routine and preventive care, and coordinates your care with specialists. HMO plans typically require you to choose a PCP and get referrals through them.Related terms:Specialist Referral HMO (Health Maintenance Organization)Provider Directory
ReferralBeginner: Written approval from your primary care doctor for you to see a specialist or get certain services, required by most HMO plans before the visit is covered. PPO plans generally don't require referrals.Related terms:Primary Care Physician (PCP)Specialist HMO (Health Maintenance Organization)PPO (Preferred Provider Organization)
Skilled Nursing Facility (SNF)Intermediate: A facility providing skilled nursing or rehabilitation care — like physical therapy after a hospital stay — that Medicare Part A covers for limited periods after a qualifying 3-day inpatient hospital stay. Coverage is measured per benefit period, with daily coinsurance after day 20.Related terms:Medicare Part A Benefit Period Observation Status Hospice Care
SpecialistBeginner: A doctor focused on one area of medicine — like a cardiologist, dermatologist, or oncologist. Depending on your plan type, seeing a specialist may require a referral from your primary care doctor and usually carries a higher copay.Related terms:Primary Care Physician (PCP)Referral Copay Network
TelehealthBeginner: Medical care delivered remotely by phone or video — for visits like follow-ups, mental health care, and chronic condition check-ins. Medicare and most private plans now cover many telehealth services, which is especially valuable in rural areas like much of Wyoming.Related terms:Medicare Part B Primary Care Physician (PCP)Network

11 terms

Insurance Costs

CoinsuranceBeginner: The percentage of a covered service's cost you're responsible for paying after you've met your deductible, with your insurance covering the rest. For example, 20% coinsurance means you pay 20% of the bill and your plan pays 80%.Related terms:Copay Deductible Out-of-Pocket Maximum Cost Sharing
CopayBeginner: A fixed dollar amount you pay for a specific covered service, like $25 for a primary care visit, regardless of the total cost of that service. Copays are usually simpler to predict than coinsurance, since the amount doesn't change based on the bill.Related terms:Coinsurance Premium Cost Sharing Drug Tier
Cost SharingBeginner: The umbrella term for the portion of healthcare costs you pay yourself — deductibles, copays, and coinsurance — as opposed to the premium you pay just to have coverage. Plans balance cost sharing against premiums: lower premiums usually mean more cost sharing when you use care.Related terms:Deductible Copay Coinsurance Cost-Sharing Reduction (CSR)
Cost-Sharing Reduction (CSR)Intermediate: An extra ACA subsidy that lowers your deductibles, copays, and out-of-pocket maximum — on top of the premium tax credit — if your income qualifies and you choose a Silver plan. It can turn a standard Silver plan into coverage that rivals Gold or Platinum at a Silver price.Related terms:Premium Tax Credit Metal Tiers (Bronze, Silver, Gold, Platinum)Federal Poverty Level (FPL)Cost Sharing
DeductibleBeginner: The amount you pay for covered healthcare services before your insurance plan starts to pay its share. Plans with lower deductibles usually have higher monthly premiums, and vice versa.Related terms:Premium Coinsurance Out-of-Pocket Maximum Part B Deductible
Federal Poverty Level (FPL)Intermediate: The income benchmark the government updates yearly and uses to set eligibility for programs like Medicaid, ACA subsidies, and Extra Help — usually expressed as a percentage, like '138% of FPL.' Where your household income falls relative to FPL largely determines which assistance you qualify for.Related terms:Medicaid Premium Tax Credit Extra Help (Low-Income Subsidy / LIS)MAGI (Modified Adjusted Gross Income)
MAGI (Modified Adjusted Gross Income)Advanced: The income measure used to determine ACA subsidy eligibility, Medicaid eligibility in most states, and Medicare IRMAA surcharges — roughly your adjusted gross income plus tax-exempt interest, non-taxable Social Security, and excluded foreign income. Small MAGI changes near a threshold can meaningfully change what you pay.Related terms:Premium Tax Credit IRMAA (Income-Related Monthly Adjustment Amount)Federal Poverty Level (FPL)Medicaid
Metal Tiers (Bronze, Silver, Gold, Platinum)Beginner: The four ACA Marketplace plan levels that describe how costs are split on average: Bronze plans have the lowest premiums but highest cost sharing, while Platinum is the reverse. Silver plans are special — they're the only tier where cost-sharing reductions apply if your income qualifies.Related terms:ACA (Affordable Care Act)Cost-Sharing Reduction (CSR)Premium Tax Credit Catastrophic Plan
Out-of-Pocket MaximumBeginner: The most you'll have to pay for covered services in a plan year through deductibles, copays, and coinsurance combined. Once you hit that limit, your plan pays 100% of covered costs for the rest of the year.Related terms:Maximum Out-of-Pocket (MOOP)Deductible Coinsurance Cost Sharing
PremiumBeginner: The amount you pay, usually monthly, to keep an insurance policy active — regardless of whether you use any healthcare services that month. It's separate from deductibles, copays, and coinsurance, which you only pay when you actually use care.Related terms:Deductible Copay Coinsurance Part B Premium
Premium Tax CreditIntermediate: The ACA subsidy that lowers your monthly Marketplace premium based on your household income and family size, paid directly to your insurer in advance or claimed at tax time. Your final credit is reconciled on your tax return against your actual income for the year.Related terms:ACA (Affordable Care Act)MAGI (Modified Adjusted Gross Income)Federal Poverty Level (FPL)Cost-Sharing Reduction (CSR)

7 terms

Government Assistance

Extra Help (Low-Income Subsidy / LIS)Intermediate: A federal program that pays most Medicare Part D costs — premiums, deductibles, and copays — for people with limited income and resources, and eliminates the Part D late enrollment penalty. You apply free through Social Security, and qualifying automatically gives you a Special Enrollment Period.Related terms:Medicare Part D Medicare Savings Programs (MSPs)Federal Poverty Level (FPL)SSA (Social Security Administration)
MedicaidBeginner: The joint federal-state health program for people with limited income and resources, covering services Medicare doesn't (like long-term care) and helping pay Medicare costs for those who qualify for both. Eligibility rules vary by state — Utah expanded Medicaid under the ACA while Wyoming did not.Related terms:Dual Eligible Medicare Savings Programs (MSPs)Federal Poverty Level (FPL)QMB (Qualified Medicare Beneficiary)
Medicare Savings Programs (MSPs)Intermediate: State-administered programs that pay some or all of your Medicare costs — most commonly the Part B premium — if your income and assets fall under the limits. The main types are QMB, SLMB, and QI, and qualifying for any of them also automatically qualifies you for Extra Help with drug costs.Related terms:QMB (Qualified Medicare Beneficiary)SLMB (Specified Low-Income Medicare Beneficiary)Extra Help (Low-Income Subsidy / LIS)Part B Premium Medicaid
PACE (Program of All-Inclusive Care for the Elderly)Advanced: A Medicare-Medicaid program that provides coordinated medical care, meals, transportation, and social services — usually through an adult day health center — so frail seniors who qualify for nursing home care can keep living at home. Availability depends on whether a PACE organization serves your area.Related terms:Medicaid Dual Eligible Skilled Nursing Facility (SNF)
QMB (Qualified Medicare Beneficiary)Advanced: The most comprehensive Medicare Savings Program: it pays your Part A and Part B premiums plus deductibles, coinsurance, and copays, and providers are prohibited from billing you for Medicare cost sharing at all. It's meant for beneficiaries with the lowest incomes.Related terms:Medicare Savings Programs (MSPs)SLMB (Specified Low-Income Medicare Beneficiary)Dual Eligible Balance Billing
SHIP (State Health Insurance Assistance Program)Beginner: The federally funded network of free, unbiased Medicare counselors in every state — volunteers who help beneficiaries understand options, compare plans, and resolve problems, with no sales involved. Every state runs one, including Wyoming and Utah.Related terms:CMS (Centers for Medicare & Medicaid Services)Medicare & You Handbook Medicare Savings Programs (MSPs)
SLMB (Specified Low-Income Medicare Beneficiary)Advanced: A Medicare Savings Program that pays your monthly Part B premium if your income is slightly above the QMB limit. Getting SLMB also automatically enrolls you in Extra Help for prescription drug costs.Related terms:Medicare Savings Programs (MSPs)QMB (Qualified Medicare Beneficiary)Extra Help (Low-Income Subsidy / LIS)Part B Premium

8 terms

Claims & Billing

Advance Beneficiary Notice (ABN)Advanced: A form a provider gives you before delivering a service they believe Original Medicare may not cover, so you can decide whether to receive it and accept responsibility for the cost. Signing an ABN doesn't mean you must pay — you can still ask for the claim to be submitted and appeal a denial.Related terms:Medically Necessary Appeal Claim Original Medicare
AppealIntermediate: Your formal right to challenge a coverage or payment decision — like a denied claim, service, or medication — through a multi-level review process with strict deadlines at each step. Many denials are overturned on appeal, so it's almost always worth filing the first level.Related terms:Grievance Prior Authorization Medically Necessary Formulary Exception
Balance BillingIntermediate: When a provider bills you for the difference between their charge and what your insurance paid — generally prohibited for in-network care, Medicare assignment providers, and QMB enrollees, and restricted for emergencies under the federal No Surprises Act. If you get an unexpected balance bill, it's often worth challenging.Related terms:Medicare Assignment Out-of-Network QMB (Qualified Medicare Beneficiary)Part B Excess Charges
ClaimBeginner: The formal request for payment your provider (or you) submits to Medicare or your insurance plan after you receive care. Most providers file claims for you; tracking them on your MSN or EOB helps catch errors early.Related terms:Explanation of Benefits (EOB)Medicare Summary Notice (MSN)Appeal Balance Billing
Coordination of BenefitsAdvanced: The rules that decide which insurance pays first when you have more than one — for example, Medicare plus an employer plan, retiree coverage, or workers' compensation. The 'primary payer' pays your claims first and the secondary may pick up remaining costs, and getting the order wrong causes claim denials.Related terms:Medicare Secondary Payer Claim COBRA Creditable Coverage
Explanation of Benefits (EOB)Beginner: The statement your insurance plan sends after processing a claim, showing what the provider billed, what the plan paid, and what you may owe. It is not a bill — compare it against any bill you receive before paying.Related terms:Claim Medicare Summary Notice (MSN)Balance Billing Appeal
GrievanceIntermediate: A formal complaint to your plan about anything other than a coverage decision — like poor customer service, long waits, or how a plan communicated with you. It's different from an appeal, which challenges what the plan will or won't pay for.Related terms:Appeal Star Ratings CMS (Centers for Medicare & Medicaid Services)
Prior AuthorizationIntermediate: A requirement that your insurance plan approve a specific service, procedure, or medication before you receive it, in order for it to be covered. It's a way plans confirm a treatment is medically necessary before agreeing to pay for it, and it applies across many types of insurance, not just Medicare.Related terms:Appeal Medically Necessary Step Therapy Referral

7 terms

Provider Networks

EPO (Exclusive Provider Organization)Intermediate: A hybrid plan type: like an HMO, it only covers care within its network (except emergencies), but like a PPO, it usually doesn't require referrals to see specialists. EPOs are common in ACA Marketplace offerings.Related terms:HMO (Health Maintenance Organization)PPO (Preferred Provider Organization)Network ACA (Affordable Care Act)
HMO (Health Maintenance Organization)Beginner: A plan type that covers care only from its own provider network (except emergencies), usually requires choosing a primary care doctor, and needs referrals to see specialists. HMOs typically trade that flexibility for lower premiums and out-of-pocket costs.Related terms:PPO (Preferred Provider Organization)Primary Care Physician (PCP)Referral Network
NetworkBeginner: The group of doctors, hospitals, and other providers that have agreed to specific rates with your insurance plan. Staying in-network usually means lower costs, while going out-of-network can mean higher costs or, with some plans, no coverage at all.Related terms:HMO (Health Maintenance Organization)PPO (Preferred Provider Organization)Out-of-Network Provider Directory
Out-of-NetworkBeginner: Care from providers who don't have a contract with your plan — covered at a higher cost by PPO and POS plans, and usually not covered at all (except emergencies) by HMO and EPO plans. Always confirm a provider's network status before scheduled care; directories can lag reality.Related terms:Network Balance Billing PPO (Preferred Provider Organization)HMO (Health Maintenance Organization)
POS (Point of Service)Intermediate: A plan type that blends HMO and PPO features: you choose a primary care doctor and need referrals like an HMO, but you can go out-of-network at a higher cost like a PPO. Less common than HMOs and PPOs, but they appear in both Medicare Advantage and employer coverage.Related terms:HMO (Health Maintenance Organization)PPO (Preferred Provider Organization)Referral Out-of-Network
PPO (Preferred Provider Organization)Beginner: A plan type that lets you see any provider without referrals — paying less in-network and more out-of-network. PPOs cost more than HMOs on average but suit people who travel, split time between states, or want to keep specific doctors.Related terms:HMO (Health Maintenance Organization)Out-of-Network Network EPO (Exclusive Provider Organization)
Provider DirectoryBeginner: A plan's official list of in-network doctors, hospitals, and pharmacies, available on the plan's website or by request. Directories change mid-year, so the safest practice is to verify with both the directory and the provider's office before you book.Related terms:Network Out-of-Network Primary Care Physician (PCP)Preferred Pharmacy

9 terms

Insurance Terms

Catastrophic PlanIntermediate: A low-premium, very-high-deductible ACA Marketplace plan available mainly to people under 30 (or those with a hardship exemption), covering three primary care visits and preventive care before the deductible. It protects against worst-case medical bills while you pay routine costs yourself.Related terms:Metal Tiers (Bronze, Silver, Gold, Platinum)Deductible ACA (Affordable Care Act)Essential Health Benefits
Essential Health BenefitsIntermediate: The ten categories of care — including hospitalization, prescription drugs, maternity, mental health, and preventive services — that every ACA Marketplace plan must cover by law. Plans sold outside the Marketplace, like short-term policies, don't have to include them.Related terms:ACA (Affordable Care Act)Metal Tiers (Bronze, Silver, Gold, Platinum)Exclusions Catastrophic Plan
ExclusionsIntermediate: Services, conditions, or situations a policy specifically does not cover, listed in the policy documents. Reading the exclusions section before buying — especially for supplemental products like cancer, accident, or short-term plans — tells you more about a policy than the marketing does.Related terms:Rider Waiting Period Medically Necessary Essential Health Benefits
Grace PeriodIntermediate: The window after a missed premium payment during which your coverage stays active while you catch up — its length varies by product, and ACA enrollees receiving subsidies get a longer one. If the grace period ends unpaid, the policy can be terminated back to the missed date.Related terms:Premium Effective Date Disenrollment Policyholder
PolicyholderBeginner: The person who owns an insurance policy and is responsible for its premiums — who may or may not be the person covered. On a family health plan, the policyholder is typically the person who enrolled the household.Related terms:Beneficiary Premium Grace Period
Pre-Existing ConditionBeginner: A health issue you had before new coverage starts. ACA Marketplace plans and Medicare can't deny you or charge more for pre-existing conditions, but Medigap insurers can consider them if you apply outside protected windows, and some other products (like short-term plans) still exclude them.Related terms:Guaranteed Issue Underwriting Medigap Open Enrollment Period ACA (Affordable Care Act)
RiderIntermediate: An optional add-on to an insurance policy that changes or expands its coverage, usually for an extra cost. Common examples include a waiver-of-premium rider on a life insurance policy, or a rider that adds a specific benefit not included in the base policy.Related terms:Policyholder Exclusions Underwriting
UnderwritingIntermediate: The process an insurance company uses to evaluate risk before issuing a policy — reviewing factors like health history, age, or lifestyle to decide whether to approve coverage and at what price. Some insurance, like Medigap during your initial enrollment window or ACA Marketplace plans, is guaranteed regardless of underwriting; other insurance, like most life insurance, relies on it heavily.Related terms:Guaranteed Issue Pre-Existing Condition Medigap Open Enrollment Period
Waiting PeriodIntermediate: A stretch of time after coverage starts during which certain benefits aren't yet payable — common in dental, vision, and final expense policies for major services. Knowing the waiting periods before you buy prevents unpleasant surprises when you need care.Related terms:Effective Date Exclusions Pre-Existing Condition

6 terms

Acronyms

ACA (Affordable Care Act)Beginner: The 2010 law — often called Obamacare — that created the Health Insurance Marketplace, premium subsidies, guaranteed coverage of pre-existing conditions, and the requirement that plans cover essential health benefits. It's the main coverage path for people under 65 without job-based insurance.Related terms:Open Enrollment (ACA Marketplace)Premium Tax Credit Metal Tiers (Bronze, Silver, Gold, Platinum)Essential Health Benefits
CMS (Centers for Medicare & Medicaid Services)Beginner: The federal agency that runs Medicare, works with states on Medicaid and CHIP, and oversees the ACA Marketplace — setting each year's premiums, deductibles, and plan rules. When you hear that a Medicare figure 'changed this year,' CMS is who changed it.Related terms:SSA (Social Security Administration)Medicare & You Handbook Star Ratings ACA (Affordable Care Act)
COBRAIntermediate: The federal law letting you keep your employer health plan for up to 18–36 months after leaving a job — but paying the full premium yourself plus a 2% fee. Important Medicare trap: COBRA is not creditable coverage for Part B, so delaying Medicare enrollment because you have COBRA can trigger permanent penalties.Related terms:Creditable Coverage Late Enrollment Penalty Qualifying Life Event Special Enrollment Period
HSA (Health Savings Account)Intermediate: A tax-advantaged savings account paired with a high-deductible health plan, where contributions, growth, and qualified medical withdrawals are all tax-free. Key Medicare rule: you can spend HSA funds in retirement (including on Medicare premiums), but you can no longer contribute once you're enrolled in any part of Medicare.Related terms:Deductible Medicare Part A Premium Initial Enrollment Period (IEP)
SSA (Social Security Administration)Beginner: The federal agency that handles Medicare enrollment, premium collection through benefit checks, IRMAA determinations, and Extra Help applications — as well as retirement and disability benefits. You enroll in Medicare through SSA, not through Medicare itself.Related terms:CMS (Centers for Medicare & Medicaid Services)Automatic Enrollment IRMAA (Income-Related Monthly Adjustment Amount)Extra Help (Low-Income Subsidy / LIS)
TRICARE for LifeIntermediate: The military retiree benefit that acts as automatic secondary coverage to Medicare for those with Parts A and B — Medicare pays first and TRICARE for Life picks up most remaining costs, including drugs through its own pharmacy benefit. Enrolling in Part B on time is essential to keep it.Related terms:Medicare Secondary Payer Creditable Coverage Medicare Part B Coordination of Benefits

7 terms

Advanced Medicare Topics

Annual Notice of Change (ANOC)Intermediate: The letter your Medicare Advantage or Part D plan must send each September detailing exactly what will change January 1 — premiums, copays, the formulary, provider network, and benefits. Reading your ANOC before the Annual Enrollment Period is the single best habit for avoiding unpleasant January surprises.Related terms:Annual Enrollment Period (AEP)Formulary Supplemental Benefits Star Ratings
Donut Hole (Coverage Gap)Intermediate: The old Medicare Part D coverage gap where drug costs jumped after your plan paid a set amount — a structure that no longer exists, replaced by a single annual out-of-pocket cap on covered drugs. The term still circulates widely, so it's worth knowing it describes how Part D used to work, not how it works now.Related terms:Part D Out-of-Pocket Cap Medicare Part D Formulary
ESRD (End-Stage Renal Disease)Advanced: Permanent kidney failure requiring dialysis or a transplant — one of the two conditions (along with ALS) that qualify people for Medicare before age 65 regardless of age. ESRD Medicare has its own enrollment timing and coordination rules with employer coverage.Related terms:Medicare Part A Medicare Part B Coordination of Benefits Automatic Enrollment
Hospice CareIntermediate: Comfort-focused care for people with a terminal illness and a life expectancy of six months or less, covered almost entirely by Medicare Part A — including nursing, medications for symptom relief, equipment, and family respite care. Choosing hospice means shifting from curative treatment to comfort, and you can leave hospice if your condition improves.Related terms:Medicare Part A Skilled Nursing Facility (SNF)Medically Necessary
Lifetime Reserve DaysAdvanced: An extra bank of 60 hospital days Medicare Part A gives you to use — once, over your lifetime — if a single hospital stay runs past 90 days in one benefit period, with a daily coinsurance set each year. Once used, they don't renew, which is one of the gaps Medigap plans cover.Related terms:Benefit Period Medicare Part A Part A Deductible Medicare Supplement (Medigap)
Medicare Secondary PayerAdvanced: Situations where another insurer must pay your claims before Medicare does — most commonly when you're still working past 65 with coverage from an employer with 20 or more employees. The employer-size rule decides whether you can safely delay Part B, so it's a critical detail for people working past 65.Related terms:Coordination of Benefits Creditable Coverage Late Enrollment Penalty Medicare Part B
Observation StatusAdvanced: When a hospital keeps you overnight as an outpatient 'under observation' instead of formally admitting you — which means Part B (not Part A) rules apply, and those days may not count toward the 3-day inpatient stay required for skilled nursing facility coverage. Always ask whether you've been admitted as an inpatient or are under observation.Related terms:Skilled Nursing Facility (SNF)Medicare Part A Medicare Part B Benefit Period