Reference

Medicare glossary for Arizona

Plain-language definitions of the Medicare words you'll see on notices, plan documents and enrollment forms, including the Arizona names that come up for people who also qualify for AHCCCS (Arizona's Medicaid program), ALTCS long-term care or the American Indian Health Program.

Jump to a letter: A · B · C · D · E · F · G · H · I · L · M · N · O · P · Q · R · S · T · U · V

ABN (Advance Beneficiary Notice of Noncoverage)

A form a doctor, lab or supplier with Original Medicare gives you before a service when they think Medicare may not pay for it. If you sign it and get the service, you may have to pay if Medicare denies the claim. You can still ask them to bill Medicare so you keep your right to appeal.

AEP (Annual Enrollment Period)

October 15 to December 7 each year. You can join, switch or drop a Medicare Advantage plan or a Part D drug plan, and changes start January 1. Medicare also calls it the Open Enrollment Period. The AEP for 2027 coverage runs October 15 to December 7, 2026. See enrollment periods.

AHCCCS (Arizona Health Care Cost Containment System)

Arizona's Medicaid program, pronounced "access." It covers people with limited income and runs the state's Medicare Savings Programs and the ALTCS long-term care program. People with both Medicare and AHCCCS are called dual eligible. See AHCCCS and Medicare.

AIHP (American Indian Health Program)

An AHCCCS fee-for-service program for eligible American Indian and Alaska Native members, covering physical and behavioral health. AHCCCS says these members may choose AIHP or an AHCCCS Complete Care health plan and can switch at any time. See Tribal Nations and IHS.

ALTCS (Arizona Long Term Care System)

The part of AHCCCS that pays for long-term care, such as a nursing facility, assisted living or care at home, for people who meet its income, resource and medical rules. A medical assessment checks whether you need a nursing-facility level of care. Tribal ALTCS serves members living on reservations.

Appeal

A request to review a decision not to cover or pay for a service, item or drug. Medicare appeals have five levels, and the first step and deadline are printed on your notice. See Medicare appeals in Arizona.

Assignment

A provider's agreement to accept the Medicare-approved amount as full payment for covered services. If your doctor accepts assignment, you pay only your deductible and coinsurance, and the doctor bills Medicare for you.

Benefit period

How Original Medicare measures your use of hospital and skilled nursing care. It starts the day you're admitted as an inpatient and ends when you've had no inpatient or skilled nursing care for 60 days in a row. You pay the Part A deductible ($1,736 in 2026) for each benefit period, so you can owe it more than once a year.

CMS (Centers for Medicare & Medicaid Services)

The federal agency that runs Medicare, approves Medicare Advantage and Part D plans, and oversees state Medicaid programs such as AHCCCS. Social Security handles Medicare sign-up.

Coinsurance

Your share of a covered cost, as a percentage. After the Part B deductible, you usually pay 20% of the Medicare-approved amount for doctor visits and outpatient care under Original Medicare.

Copayment (copay)

A set dollar amount you pay for a service or prescription, such as a doctor visit or a 30-day supply of a drug. Medicare Advantage and Part D plans set their own copays.

Coverage determination

A Part D plan's decision about whether it will cover a drug and how much you pay. You can ask for one, including an exception to the plan's formulary or rules, and appeal if the answer is no.

Creditable coverage

Drug coverage expected to pay on average at least as much as standard Part D. Keeping creditable coverage, for example from a job, the VA, TRICARE or the Indian Health Service and tribal programs, protects you from the Part D late enrollment penalty. Your plan tells you each year in a creditable coverage notice.

D-SNP (Dual Eligible Special Needs Plan)

A Medicare Advantage plan only for people who have both Medicare and Medicaid (in Arizona, AHCCCS). D-SNPs coordinate the two programs and must have a contract with the state. AHCCCS publishes its D-SNP agreements.

Deductible

What you pay before Medicare or your plan starts to pay. In 2026 the Part B deductible is $283 a year, the Part A deductible is $1,736 per benefit period, and Part D plans can have a deductible of up to $615.

DIFI (Arizona Department of Insurance and Financial Institutions)

The state agency that licenses insurance companies and agents in Arizona and regulates Medigap policies sold here. You can check an agent's license or file a complaint about an insurance company with DIFI.

Dual eligible

A person who has both Medicare and Medicaid. Full dual eligibles get full AHCCCS benefits; partial dual eligibles get help only through a Medicare Savings Program. Medicare pays first, then AHCCCS.

EOB (Explanation of Benefits)

A statement from a Medicare Advantage or Part D plan showing the services or drugs it paid for, what it paid and what you may owe. It is not a bill. Part D EOBs also show your progress toward the yearly out-of-pocket cap.

EPD (Elderly and Physically Disabled)

The ALTCS program for people 65 or older, blind or with a physical disability who need a nursing-facility level of care. AHCCCS enrolls EPD members with a program contractor in their county, or with a tribal contractor for American Indian members living on a reservation.

Evidence of Coverage (EOC)

The full legal description of what a Medicare Advantage or Part D plan covers, what you pay, and your rights and appeal steps. Plans send it each fall for the next year. It has more detail than the Summary of Benefits.

Excess charge

The extra amount a doctor who doesn't accept assignment can bill you, above the Medicare-approved amount, under Original Medicare. Federal law caps it at 15% over the amount Medicare allows for that doctor. Medigap Plans F and G cover excess charges.

Extra Help

A federal program, also called the Part D Low-Income Subsidy, that helps pay Part D premiums, deductibles and copays. In 2026 the yearly income limit is $23,940 for one person. People in AHCCCS or a Medicare Savings Program qualify automatically. You can apply through Social Security.

Formulary

A plan's list of covered drugs, usually sorted into tiers. Formularies differ from plan to plan and can change each year, so check that your drugs are on it before you join.

GEP (General Enrollment Period)

January 1 to March 31 each year, for people who missed their Initial Enrollment Period and don't qualify for a Special Enrollment Period. Coverage starts the month after you sign up, and a late enrollment penalty may apply.

Guaranteed issue rights

Situations in which a Medigap company must sell you a policy and can't charge more for health conditions, for example when your Medicare Advantage plan leaves your area. Federal law sets these rights. See when you can buy Medigap in Arizona.

Health-e-Arizona Plus

Arizona's online application portal at healthearizonaplus.gov for medical, nutrition and cash assistance, including AHCCCS and the Medicare Savings Programs. You can apply, upload documents and renew there.

HMO (Health Maintenance Organization)

A type of Medicare Advantage plan that generally requires you to use doctors and hospitals in its network, except for emergencies and urgently needed care. Some HMOs require referrals to see specialists.

IEP (Initial Enrollment Period)

Your first chance to sign up for Medicare: seven months that start three months before the month you turn 65 and end three months after it. Signing up before your birthday month means coverage starts the month you turn 65.

IHS (Indian Health Service)

The federal agency that provides health care to members of federally recognized tribes. Arizona is served by the Phoenix, Navajo and Tucson IHS Areas, along with tribal and urban Indian programs. Medicare generally pays before IHS. See using IHS and Medicare.

Inpatient

Formally admitted to a hospital on a doctor's order. Inpatient care is covered by Part A. Staying overnight doesn't by itself make you an inpatient; see observation status.

IRMAA (Income-Related Monthly Adjustment Amount)

An extra amount added to Part B and Part D premiums for people with higher income. For 2026 it applies when modified adjusted gross income from your 2024 tax return was above $109,000 (single) or $218,000 (married filing jointly). The brackets are cliffs: one dollar over a line moves you to the next amount. Try the IRMAA calculator.

Late enrollment penalty

An amount added to your premium if you sign up late. For Part B it is 10% for each full 12 months you could have had Part B but didn't, usually for as long as you have Part B. For Part D it applies after 63 days or more in a row without Part D or creditable coverage. See the penalty calculator.

Lifetime reserve days

Sixty extra hospital days Original Medicare covers over your lifetime after day 90 of a hospital stay. In 2026 you pay $868 for each one you use. Once used, they don't come back.

MA OEP (Medicare Advantage Open Enrollment Period)

January 1 to March 31 each year. If you're in a Medicare Advantage plan, you can switch to another one or go back to Original Medicare (and join a Part D plan) once during this time. People new to Medicare Advantage also get it during their first three months of Medicare.

Medicare Advantage (Part C)

Plans from private companies approved by Medicare that provide your Part A and Part B coverage, usually with drug coverage, through a network. Plans are approved county by county; for 2027, 16 companies offer Medicare Advantage plans in Arizona (CMS plan data). See Medicare Advantage in Arizona.

Medicare-approved amount

The amount Medicare sets as payment for a covered service. Your coinsurance is figured from it. A provider who accepts assignment takes it as full payment.

Medicare Summary Notice (MSN)

A statement Original Medicare mails every four months if you had services, listing what providers billed, what Medicare paid and the most you may owe. It's not a bill, and it explains how to appeal. You can also see claims in your Medicare.gov account.

Medigap (Medicare Supplement Insurance)

Private insurance that works with Original Medicare to pay some of what it leaves, such as deductibles and the 20% coinsurance. Plans are standardized by letter (A, B, C, D, F, G, K, L, M, N), so the same letter has the same benefits from every company; prices differ. DIFI regulates Medigap in Arizona. See Medigap in Arizona.

Medigap open enrollment period

Six months that start the first month you're both 65 or older and enrolled in Part B. During it, a Medigap company must sell you any policy it offers in Arizona at its standard rate, regardless of your health.

MOOP (maximum out-of-pocket limit)

The most you pay in a year for covered Part A and Part B services in a Medicare Advantage plan. CMS sets the highest limit plans may use ($9,250 for in-network services in 2026); each plan sets its own. Original Medicare has no such limit.

MSP (Medicare Savings Programs)

State programs that pay Medicare premiums, and for some people deductibles and coinsurance. In Arizona, AHCCCS runs three: QMB, SLMB and QI-1. See Medicare Savings Programs in Arizona.

Network

The doctors, hospitals, pharmacies and other providers a plan contracts with. Medicare Advantage networks are local, which matters if you split the year between Arizona and another state.

Observation status

Hospital care as an outpatient while doctors decide whether to admit you. It's billed under Part B, and days under observation don't count toward the three inpatient days needed for Original Medicare to cover skilled nursing care. If you're under observation more than 24 hours, the hospital must give you a Medicare Outpatient Observation Notice (MOON).

Original Medicare

Part A and Part B, run by the federal government. You can use any doctor or hospital in the U.S. that accepts Medicare, and you can add a Medigap policy and a Part D plan.

PACE (Program of All-Inclusive Care for the Elderly)

A Medicare and Medicaid program that provides medical care and long-term services through one local organization, for people 55 and older who need a nursing-home level of care but can live safely at home. PACE is offered only where a PACE organization operates; check Medicare.gov or AHCCCS for whether one serves your ZIP code.

Part A (hospital insurance)

Covers inpatient hospital stays, skilled nursing care after a qualifying stay, hospice and some home health care. Most people pay no premium for Part A because they or a spouse paid Medicare taxes for at least 10 years. See Part A.

Part B (medical insurance)

Covers doctor visits, outpatient care, lab tests, durable medical equipment and preventive services. The standard premium is $202.90 a month in 2026. See Part B.

Part D (prescription drug coverage)

Drug coverage from private plans, either a standalone Part D plan with Original Medicare or as part of a Medicare Advantage plan. In 2026 your out-of-pocket costs for covered drugs are capped at $2,100 for the year, and covered insulin costs no more than $35 for a month's supply. See Part D in Arizona.

PFFS (Private Fee-for-Service plan)

A type of Medicare Advantage plan that sets how much it pays providers. Some PFFS plans have networks; with others you can see any Medicare provider who agrees to the plan's terms before each visit.

PPO (Preferred Provider Organization)

A type of Medicare Advantage plan with a network that also pays for covered care outside the network, usually at a higher cost to you.

Premium

The amount you pay each month for coverage, such as the Part B premium or a plan's premium. If you have a Medicare Advantage plan, you keep paying your Part B premium.

Preventive services

Care to prevent illness or find it early, such as flu shots, screenings and the yearly wellness visit. Many are covered by Part B with no cost to you when the provider accepts assignment.

Prior authorization

Approval you or your provider must get from a plan before it will cover a service or drug. Medicare Advantage and Part D plans use it; Original Medicare uses it only for a few services.

QI-1 (Qualifying Individual)

A Medicare Savings Program that pays your Part B premium. In Arizona it's called the QI1 Part B Buy-In, for incomes above 120% and up to 135% of the federal poverty level. You can't get QI-1 if you qualify for other AHCCCS coverage.

QMB (Qualified Medicare Beneficiary)

A Medicare Savings Program that pays Part A premiums (if you owe one), Part B premiums, and Medicare deductibles, coinsurance and copays. AHCCCS calls it QMB Only, for incomes up to 100% of the federal poverty level. Providers may not bill people in QMB for Medicare-covered cost sharing.

Referral

An order from your primary care doctor to see a specialist. Some Medicare Advantage HMOs require one; Original Medicare doesn't.

SEP (Special Enrollment Period)

A chance to sign up for or change coverage outside the usual windows because of a life event, such as moving, losing job-based coverage, your plan leaving your area, or getting AHCCCS or Extra Help. See when you can change your plan.

Service area

The counties where a Medicare Advantage or Part D plan is offered. You must live in the service area to join, and a plan can disenroll you if you're away more than six months.

Skilled nursing facility (SNF)

A facility with skilled nursing or rehab staff. Original Medicare covers up to 100 days per benefit period after a qualifying inpatient stay of at least three days; in 2026 you pay $217 a day for days 21 to 100. Medicare doesn't cover long-term custodial care; in Arizona, ALTCS may.

SLMB (Specified Low-Income Medicare Beneficiary)

A Medicare Savings Program that pays your Part B premium. AHCCCS calls it the SLMB Part B Buy-In, for incomes above 100% and up to 120% of the federal poverty level.

SNP (Special Needs Plan)

A Medicare Advantage plan limited to people with certain needs: both Medicare and Medicaid (D-SNP), certain chronic conditions (C-SNP), or living in an institution (I-SNP). For 2027 there are 57 special needs plans in Arizona (CMS plan data).

Step therapy

A plan rule that you try a lower-cost drug first before it covers a similar, higher-cost drug. You or your prescriber can ask for an exception.

Summary of Benefits

A short document showing a Medicare Advantage or Part D plan's main costs and covered services. Read it with the Evidence of Coverage before you choose.

Tier

A level on a plan's formulary. Drugs on lower tiers usually cost you less than drugs on higher tiers.

TPMO (third-party marketing organization)

CMS's term for agents, agencies and companies that sell Medicare plans for insurance companies. Benefits Life, the publisher of this site, is a TPMO, which is why each page shows the CMS disclaimer about the plans we represent.

TRICARE For Life

Coverage for military retirees and eligible family members with Medicare that pays after Medicare. You must have Part A and Part B to keep it. See veterans and military.

Urgently needed care

Care for a sudden illness or injury that isn't an emergency but can't wait. Medicare Advantage plans must cover it when you're temporarily outside the plan's service area, in the U.S.

VA health care

Care from the Department of Veterans Affairs, including the Phoenix, Tucson and Prescott VA systems. VA and Medicare don't coordinate payment: VA pays for care at VA facilities, Medicare for care elsewhere. VA drug coverage is creditable for Part D.

Visitor/traveler program

An option some Medicare Advantage plans offer that lets you stay enrolled while you're out of the service area within the U.S. for more than six months, up to 12. See snowbirds and Medicare plans.

Sources

Frequently asked questions

What is the difference between AHCCCS and Medicare?

Medicare is the federal health insurance program for people 65 and older and some younger people with disabilities. AHCCCS is Arizona's Medicaid program, which is based on income and other rules. Some Arizonans have both; Medicare then pays first, and AHCCCS can help with premiums and costs Medicare leaves.

What does ALTCS stand for?

ALTCS is the Arizona Long Term Care System, the part of AHCCCS that covers long-term care, such as nursing home care or care at home, for people who meet its financial and medical rules. People 65 and older and people with physical disabilities apply through the EPD (Elderly and Physically Disabled) program.

Where can I look up a Medicare term that isn't on this page?

Medicare.gov has a full glossary, and 1-800-MEDICARE can explain any term on a Medicare notice. A licensed insurance agent with Benefits Life can also help you read plan documents, at no cost to you.

Licensed insurance agents for Arizona

These independent insurance agents are licensed in Arizona and work with Benefits Life, the publisher of this site. When they enroll you in a plan, the agent and Benefits Life may be paid by the insurance company. Learn more.