- EOB (Explanation of Benefits)
- Your insurer's receipt. It's not a bill. It shows what was billed, what the insurer allowed, what it paid, and what YOU owe. That last line is the number to match against the hospital bill.
- Patient responsibility
- What you actually owe after insurance. If the hospital bills more than this, that's a red flag.
- Allowed amount
- The price your insurer agreed to. In-network providers can't bill you the difference between their sticker price and this.
- Chargemaster
- The hospital's sticker-price list. Almost nobody with insurance should pay these prices.
- Itemized bill
- The line-by-line version of your bill. Always ask for it.
- CPT / HCPCS code
- 5-character codes for what was done (a scan, a visit, a drug). The wrong code means the wrong price.
- Revenue code
- 4-digit hospital department code (for example, 020x = ICU room). It helps you check room days and supplies.
- ICD-10 code
- Diagnosis code. It explains why care was given and drives medical-necessity decisions.
- UB-04 / CMS-1500
- The claim forms hospitals (UB-04) and doctors (CMS-1500) send your insurer. Ask for a copy.
- Deductible
- What you pay each year before most insurance kicks in.
- Coinsurance / copay
- Your share after the deductible: a percent (coinsurance) or a flat fee (copay).
- Out-of-pocket max
- The most you pay in a plan year for covered in-network care. After that, your plan pays 100%.
- In-network / out-of-network
- Whether the provider has a contract with your plan. The No Surprises Act protects you in many out-of-network situations.
- Balance billing
- Billing you for the gap between the sticker price and what insurance paid. Often banned.
- Prior authorization
- Insurer pre-approval. A missing prior auth is a common reason for denials, and those denials are often fixable.
- Medical necessity
- Whether care was needed. Denials for this reason are often overturned with a doctor's letter.
- Unbundling
- Billing separately for parts of a procedure that should be one charge.
- Upcoding
- Billing a more expensive code than the care given.
- NCCI / MUE edits
- Medicare's rules for code pairs that shouldn't be billed together and the maximum units per day. Useful red flags, though commercial plans differ.
- Observation status
- You can be in a hospital bed and still be 'outpatient.' It changes what you owe, especially on Medicare. Ask: was I admitted or under observation?
- FAP / charity care
- A hospital's Financial Assistance Policy. Required at nonprofit hospitals.
- AGB (Amounts Generally Billed)
- If you qualify for financial assistance, a nonprofit hospital can't charge you more than what insured patients are generally billed.
- ECA (Extraordinary Collection Action)
- Credit reporting, lawsuits, liens, wage garnishment, selling your debt. Restricted while a charity-care application is pending.
- GFE (Good Faith Estimate)
- A written price estimate you're owed if you're uninsured or paying cash for scheduled care.
- PPDR
- Patient-Provider Dispute Resolution. Lets uninsured or cash-pay patients dispute a bill that's $400+ over the GFE.
- External review
- An independent reviewer, outside the insurer, who can overturn a denial. Only about 40% of people know it exists.