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Billing & Insurance Glossary of Terms

Here are some common terms you will encounter when dealing with billing and insurance issues.


Allowed Expenses – The maximum amount a plan pays for a covered service. See Usual and Customary Charges.

Ambulatory Care - Medical services provided on an outpatient (non-hospitalized) basis

(APC) Ambulatory Patient Classifications - A structure for classifying outpatient services and procedures for purposes of payment.

Benefits - These are medical services for which your insurance plan will pay, in full or in part.

Beneficiary - Someone who is eligible for or receiving benefits under an insurance policy or plan.

Claim - A notice to the insurance company that a person received care covered by the plan. A claim is also a request for payment.

Coding - How physician's services are identified and defined.

Co-insurance - A type of cost sharing where the beneficiary and insurance provider share payment of the approved charge for covered services.

Consolidated Omnibus Budget Reconciliation Act (COBRA) - A federal law that requires employers to offer continued health insurance coverage to certain employees and their beneficiaries whose group health insurance coverage has been terminated. Applies to employers with 20 or more eligible employees. Typically, COBRA makes continued coverage available for up to 18 or 36 months. COBRA enrollees may be required to pay 100 percent of the premium, plus an additional 2 percent.

Coordinated Coverage - Integrating benefits payable under more than one health insurance (for example, Medicare and retiree health benefits). Coordinated coverage is typically arranged so the insured benefits from all sources not exceeding 100 percent of allowable medical expenses. Coordinated coverage may require beneficiaries to pay some deductible or co-insurance.

Coordination of Benefits (COB) - A provision that applies when a person is covered under more than one group medical program. (See "Coordinated Coverage" above.)

Co-insurance - A term that describes a shared payment between an insurance company and an insured individual. It's usually described in percentages; for example, the insurance company agrees to pay 80% of covered charges and the individual picks up 20%.

Co-payment - A set fee the member pays to providers at the time services are provided. Co-pays are applied to emergency room visits, hospital admissions, office visits, etc. The patient should be aware of the co-payment amounts prior to services being rendered.

Coverage - What services the health plan does and does not pay for.

Covered Expenses - What the insurance company will consider paying for as defined in the contract. For example, under some plans generic prescriptions are covered expenses while brand name prescriptions are not.


Date Of Service (DOS) - The date(s) healthcare services were provided to the beneficiary.

Deductible - A portion of the covered expenses (typically $100, $200 or $500) that an insured individual must pay before insurance coverage with co-insurance goes into effect. Deductibles are standard in many policies, and are usually based on a calendar year.

Diagnosis-Related Groups (DRGs) - The hospital classification and reimbursement system that groups patients by diagnosis, surgical procedures, age, sex and presence of complications. This is a financing mechanism used to reimburse hospital and selected other providers for services rendered.

Duplicate Coverage Inquiry (DCI) - A request to an insurance company or group medical plan by another insurance company or medical plan to find out whether other coverage exists (see Coordinated Coverage).

Durable Medical Equipment (DME) - Medical equipment which: can withstand repeated use; is not disposable; is used to serve a medical purpose; is generally not useful to a person in the absence of sickness or injury, and is appropriate for use in the home. Examples include hospital beds, wheelchairs and oxygen equipment.

Employee Retirement Income Security Act of 1974 (ERISA) - This law mandates reporting, disclosure of grievance and appeals requirements and financial standards for group life and health. Self-insured plans are regulated by this law.

Enrollee - The person who is covered by health insurance.

Explanation of Benefits (EOB) - The coverage statement sent to covered persons listing services rendered, amount billed and payment made. This normally would include any amounts due from the patient, as described in "Beneficiary Liability," "Co-insurance," "Deductible" and "Co-payment" all listed above.


Health Care Provider - An individual or institution that provides medical services (e.g. a physician, hospital or laboratory). This term should not be confused with an insurance company that "provides" insurance.

Health Insurance - Coverage that provides for the payment of benefits as a result of sickness or injury. Includes insurance for losses from accident, medical expense, disability, or accidental death and dismemberment.

Health Insurance Portability and Accountability Act (HIPAA) - Federal legislation to provide easier portability of medical information by standardizing electronic transaction and code sets, and enacting additional patient privacy provisions.

Health Maintenance Organization (HMO) - An entity that provides, offers or arranges for coverage of designated health services needed by plan members for a fixed, prepaid premium.

International Classification of Diseases, 9th Edition (Clinical Modification) (ICD-9-CM) - A listing of diagnosis and identifying codes used by physicians and hospitals for reporting diagnoses and procedures of health plan enrollees.

Maximum Out of Pocket - The most money you can expect to pay for covered expenses. The maximum limit varies from plan to plan. Once the maximum out-of-pocket has been met, the health plan will pay 100% of certain covered expenses.

Medicaid - A jointly-funded, Federal-State health insurance program for certain low-income and needy people. It covers many individuals including children, the aged, blind, and/or disabled, and people who are eligible to receive federally assisted income maintenance payments.

Medicare - Medicare is a federal insurance program for people age 65 and older and certain disabled people. The Centers for Medicare & Medicaid Services (CMS) operates Medicare. The Medicare program consists of two parts, Medicare Part A (hospital insurance) and Medicare Part B (supplemental medical insurance).

Medicare Benefits Notice - A notice you get after your doctor files a claim for Part A services in the Original Medicare Plan. It says what the provider billed for, the Medicare-approved amount, how much Medicare paid, and what you must pay. You might also get an Explanation of Medicare Benefits (EOMB) for Part B services or a Medicare Summary Notice (MSN).

Medicare Coverage - Made up of two parts: Hospital Insurance (Part A) and Medical Insurance (Part B). (See Medicare Part A (Hospital Insurance); Medicare Part B (Medical Insurance).)

Medicare Part A (Hospital Insurance) - Hospital insurance that pays for inpatient hospital stays, care in a skilled nursing facility, hospice care and some home health care.

Medicare Part B (Medical Insurance) - The part of Medicare that covers doctors' services and outpatient hospital care. It also covers other medical services that Part A does not cover, like physical and occupational therapy.

Medicare Secondary Payer - A statutory requirement that private insurers providing general health insurance coverage to Medicare beneficiaries pay beneficiary claims as primary payers.

Medicare Supplement Policy (Medsupp) - The insurer will pay a policyholder's Medicare co-insurance, deductible and co-payments for Medicare Part A and B and may provide additional supplement benefits according to the supplement policy selected.

Medigap Insurance - Privately purchased individual or group health insurance policies designed to supplement Medicare coverage. Benefits may include payment of Medicare deductibles, co-insurance and balance bills, as well as payment for services not covered by Medicare.

Medigap Plan - Purchased by Medicare enrollees to cover co-payments, deductibles and healthcare goods or services not paid for by Medicare. Also known as a Medicare supplements policy.

Medigap Policy - Aa privately purchased insurance policy that supplements Medicare coverage.


Network - Physicians, hospitals, and other health care providers that an HMO, PPO or other managed care network has selected to provide care for its members.

Non-Participating Provider - Also known as out-of-network provider. A healthcare provider who has not contracted with the carrier of a health plan to be a participating provider of health care.

Open Enrollment - A specified period of time in which employees may change insurance plans and medical groups offered by their employer and have the new insurance effective at a later date.

Out of Network (OON) - Coverage for treatment obtained from a non-participating provider. Typically, it requires payment of a deductible and higher co-payments and co-insurance than for treatment from a participating provider. Insurer may also deny entire bill.

Out-of-Pocket-Costs/Expenses (OOPs) - The portion of payments for covered health services required to be paid by the patient, including co-payments, co-insurance and deductible. (See "Beneficiary Liability," "Co-insurance," "Deductible" and "Co-payment" above.)

Participating Provider - A provider who has contracted with the health plan to deliver medical services to covered persons. The provider may be a hospital, pharmacy or other facility or a physician who has contractually accepted the terms and conditions as set forth by the health plan.

Part A Medicare - Medical Hospital Insurance (HI) under part A of title XVIII of Social Security Act, which covers patients for inpatient hospital, home health, hospice and limited skilled nursing facility services. Beneficiaries are responsible for deductibles and co-payments.

Part B Medicare - Medicare Supplement Medical Insurance (SMI) under Part B of Title XVII of the Social Security Act, which covers Medicare beneficiaries for physician services, medical supplies and other outpatient treatment. Beneficiaries are responsible for monthly premiums, co-payments, deductibles and balance billing.

Point-of-Service Plan (POS) - Managed care product that offers enrollees a choice among options when they need medical services, rather than when they enroll in the plan. Enrollees may use providers outside the managed care network, but usually at higher cost. (This should not be confused with POS as used in retail pharmacy, where it stands for point of sale.)

Preauthorization - An insurance plan requirement in which you or your primary care physician need to notify your insurance company in advance about certain medical procedures (like outpatient surgery) in order for those procedures to be considered a covered expense.

Pre-certification - Authorization given by a health plan for a Member to obtain services from a health care provider, most commonly required for hospital services. Members should refer to their insurance identification card or call their health plan to obtain information regarding pre-certification requirements.

Pre-existing Condition - Any medical condition that has been diagnosed or treated within a specified period immediately preceding the covered person's effective date of coverage. Pre-existing conditions may not be covered for some specified amount of time as defined in the certificate of coverage (usually six to 12 months). Individuals can be required to satisfy a pre-existing waiting period only once, so long as they maintain continuous group health plan coverage with one or more carriers.

Pre-existing Condition Exclusion - A practice of some health insurers to deny coverage to individuals for a certain period for health conditions that already exist when coverage is initiated.

Preferred Provider Organization (PPO) - A program that establishes contracts with providers of medical care. Providers under such contracts are referred to as a preferred provider. Usually, the benefit contract provides significantly better benefits and lower member costs for services received from preferred providers, thus encouraging covered persons to use these providers.

Premium - Amount paid periodically to purchase health insurance benefits.

Primary Care Physician (PCP) - A physician, the majority of whose practice is devoted to internal medicine, family/general practice and pediatrics. An obstetrician/gynecologist sometimes is considered a primary care physician, depending on coverage.


Reasonable Charge - A fee is considered "Reasonable" if it is both usual and customary or if it is justified because there is a complex problem involved.

Referral - Approval or consent by a primary care physician for patient referral to ancillary services and specialists.

Secondary Payer - An insurance policy, plan, or program that pays second on a claim for medical care. This could be Medicare, Medicaid, or other health insurance depending on the situation. For Commercial or Managed payors, if you have additional coverage through your spouse, then coverage through their insurance will be considered your secondary. For children covered under two insurance plans, primary coverage will be determined by the Subscriber (Mom or Dad) whose month of birth is closest to the beginning of the year. This is also known as the Birthday Rule.

Skilled Nursing Facility - A facility (which meets specific regulatory certification requirements) which primarily provides inpatient skilled nursing care and related services to patients who require medical, nursing, or rehabilitative services but does not provide the level of care or treatment available in a hospital.

Specialist - A physician who specializes in a specific area of medicine, such as cardiology, oncology, urology, etc. Most HMOs require members to obtain a Referral from their Primary Care Physician before setting an appointment to see a Specialist.

Sub-Acute Care - Usually described as a comprehensive inpatient program for those who have experienced a serious illness, injury or disease, but who do not require intensive hospital services. The range of services considered sub-acute can include infusion therapy, respiratory care, cardiac services, wound care, rehabilitation services, post-operative recovery programs for knee and hip replacements, cancer, stroke and AIDS care.

Subscriber - The person responsible for payment of premiums or whose employment is the basis for eligibility for membership in an HMO or other health plan.

Supplementary Medical Insurance - The Medicare program that pays for a portion of the costs of physicians' services, outpatient hospital services, and other related medical and health services for voluntarily insured aged and disabled individuals. Also known as Part B.

Third Party Administrator (TPA) - An independent person or corporate entity (third party) that administers group benefits, claims and administration for a self-insured company or group.

Usual, Customary and Reasonable (UCR) - A term used to refer to the commonly charged or prevailing fees for health services within a geographic area.

Utilization Review (UR) - Programs designed to reduce unnecessary medical services, both inpatient and outpatient. Utilization reviews may be prospective, retrospective, concurrent, or in relation to discharge planning.