26 frequently-used terms across 5topics — what each one means, what it actually changes at the doctor’s office and at tax time, and where it fits in the wider picture of a plan you can actually live with.
Reading on a phone? Jump to a section: Costs · Coverage · Network & providers · Plans & types · Enrollment
Topic 1 of 5
The money side of a plan — what you pay monthly, what you pay at the visit, and the ceiling on what you pay in a bad year.
The amount you pay out of your own pocket for covered care before the plan starts paying its share. Preventive care is typically exempt — check the plan summary. Higher deductibles usually pair with lower monthly premiums.
A fixed dollar amount you pay for a specific service at the visit — for example, $30 for a primary care visit or $15 for a generic prescription. Copays usually do not count toward your deductible, but they do count toward your out-of-pocket maximum.
After you meet your deductible, the share of a bill you and the plan split — for example, the plan pays 80% and you pay 20%. Unlike a copay, coinsurance is a percentage, so the dollar amount varies with the cost of the service.
Related: Medicare
The most you’ll pay for covered care in a plan year. Once you hit this number — across deductible, copays, and coinsurance — the plan pays 100% of covered in-network care for the rest of the year. Premiums and out-of-network care usually do not count toward this cap.
Related: Medicare
The maximum a plan will treat as the "reasonable" charge for a service. In-network providers accept this amount as payment in full; out-of-network providers can bill you the gap between their charge and the allowed amount.
Topic 2 of 5
What the plan actually pays for, the paperwork that surrounds a claim, and the rules that gate specific treatments.
The ten categories of care every ACA Marketplace plan is required to cover — including doctor visits, hospital care, prescriptions, maternity, mental health, and preventive services. They define what “comprehensive coverage” means under federal law.
Related: FAQ
Approval the plan requires before it will cover a specific service, drug, or procedure. Your doctor's office sends the request, the plan reviews it against medical-necessity criteria, and you'll get a written decision. Emergency care doesn't require prior authorization.
Related: Medicare
Routine care designed to catch problems early — annual physicals, age-appropriate screenings, immunizations, and well-woman or well-child visits. ACA plans must cover a defined set of preventive services at no cost when delivered in-network.
Related: FAQ
The standard a plan uses to decide whether a service is covered: it must be appropriate, evidence-based, and not primarily for convenience. If a claim is denied on medical-necessity grounds, your doctor can write a letter of medical necessity supporting the case.
A statement your plan sends after a claim is processed — it isn't a bill. It shows what was charged, what the plan paid, and what you may owe. Compare the EOB with the actual bill from your provider before paying anything.
Related: Medicare
Topic 3 of 5
The doctors, hospitals, and clinics your plan treats as in-network — and what changes when you go outside that list.
The group of doctors, hospitals, labs, and other providers a plan has contracted with to deliver care at negotiated rates. Always check that your specific doctors and preferred hospital are in-network before you enroll — a plan with the right coverage still misses the mark if your providers are out of network.
A provider who has contracted with your plan. In-network care is covered at the plan’s negotiated rates and counts toward your in-network out-of-pocket maximum. Out-of-network care usually costs more and may not be covered at all.
Related: Medicare
A provider who has not contracted with your plan. PPO plans cover some out-of-network care at a higher cost; HMO and EPO plans typically do not — except for true emergencies. You can be balance-billed for the gap between the provider’s charge and the plan’s allowed amount.
The doctor you see for routine care — your main clinician. Under most HMOs your PCP is the gatekeeper: they refer you to specialists and coordinate your care. PPO and EPO plans usually let you see specialists without going through a PCP first.
Written authorization from your primary care physician to see a specialist or get a specific test. Most HMO plans require a referral before the visit; PPO and EPO plans typically do not. Without a required referral, the plan can deny the claim even if the service would otherwise be covered.
Topic 4 of 5
The structural flavors of health insurance: how the network is organized, when you can see a specialist, and what trade-offs each style makes.
A plan style that uses a defined network, requires you to choose a primary care physician, and requires a referral before seeing a specialist. Out-of-network care is generally not covered except in emergencies. Premiums tend to be lower than PPOs.
Related: Compare plan types · FAQ
A plan style that uses a network but lets you see any provider — in-network at lower cost, out-of-network at higher cost — without needing a referral. Premiums tend to be higher than HMOs and the trade-off is flexibility and choice.
Related: Compare plan types · FAQ
A plan style that uses a defined network like an HMO but does not require referrals like a PPO. Out-of-network care is typically not covered except in emergencies. Often positioned between HMO and PPO on premium.
Related: Compare plan types · FAQ
A hybrid plan style that combines an HMO and a PPO: in-network care uses a PCP plus referrals (like an HMO), but out-of-network care is covered at a higher cost (like a PPO). Useful when you want PCP coordination day-to-day and occasional out-of-network flexibility.
Related: Compare plan types · FAQ
A plan with a higher annual deductible than a traditional plan — and usually a lower monthly premium. If you have an HDHP, you’re eligible to open a Health Savings Account (HSA) and contribute pre-tax dollars to pay for qualified medical expenses.
The federal health insurance program for people 65 and older, certain younger people with disabilities, and people with end-stage renal disease. Medicare is delivered in pieces: Part A (hospital), Part B (medical), Part D (prescriptions), with Medicare Advantage (Part C) bundling them through private carriers.
Related: Medicare
Topic 5 of 5
The windows and life events that let you sign up, switch, or renew coverage — outside these windows, change is normally not allowed.
The annual window when anyone eligible can enroll in, switch, or renew coverage for the coming year. ACA Marketplace Open Enrollment runs November 1 through January 15 in most states; Medicare AEP runs October 15 through December 7.
Related: FAQ
A 60-day window outside Open Enrollment triggered by a qualifying life event — losing other coverage, moving, marriage, birth of a child, or a household income change. Document the event and act quickly; the deadline is strict.
Related: FAQ
A specific change in your circumstances that opens a Special Enrollment Period. Common examples: loss of job-based coverage, a move across state lines, marriage or divorce, birth or adoption of a child, or a significant income change that affects subsidy eligibility.
Related: FAQ
Can’t find a term here? It’s likely covered on the FAQ or the Medicare page. And if reading these has surfaced a specific plan decision, we’ll walk through it with you — free.