How to read an itemized hospital bill

First, get the itemized bill

What you initially receive is usually a summary statement: totals by category, not by procedure. To audit the bill, you need the itemized bill. Request it in writing from the hospital's billing department. For facility charges, this is typically a UB-04 form. For physician charges processed separately, it's typically a CMS-1500 form.

Hospitals must provide this on request, usually within 30 days, and often free of charge.

What you'll see on a UB-04

• Revenue code — a 4-digit code identifying the department (e.g. 0450 for emergency room, 0250 for pharmacy, 0300 for labs).
• Description — plain-English line item (“CT HEAD W/O CONTRAST”).
• HCPCS/CPT code — the specific procedure code. CPT 70450 is “CT head without contrast”. This is the code the insurer prices against.
• Service date — when the procedure was performed.
• Units — how many times the service was billed.
• Total charges — billed amount for this line.

The audit pass

Work down the itemized bill and flag each line:

1. Same code, same day, same unit count? Duplicate charges are the most common error.
2. Units match reality? A blood test billed with 3 units when one draw happened is an overcharge.
3. Service codes match the care you received? Compare against your discharge summary or notes.
4. ER E/M level plausible? CPT 99281–99285 levels must match complexity. A 99285 (highest) for a simple sprain is upcoding.
5. Supplies bundled or unbundled? Basic kits, trays, and bandages should be bundled with the procedure, not line items.
6. Room & board unit count matches length of stay? A 2-night stay billed as 3 nights is an overcharge.
7. Charges for standard supplies like gloves or gowns? These should rarely appear as separate line items for inpatient care.

Compare against the EOB

Once you've identified suspicious lines, cross-check against your EOB. The insurer's claim processing may have caught some errors the hospital hasn't. Look for denied lines or adjustments.

Compare against a fair price

Tools like Healthcare Bluebook, the CMS Physician Fee Schedule, and the hospital's own public chargemaster give you benchmarks. A charge 3–10× the Medicare rate for the same CPT, in the same area, is worth a conversation.

When to bring in help

For bills over about $10,000 or complex inpatient stays with dozens of codes, a medical billing advocate (often works on contingency) or a healthcare attorney can be worth it. For most outpatient bills, a careful self-audit plus a written dispute is enough.

Fix My Bill automates most of this audit pass — but you still need a clear discharge summary and an itemized bill. Decision-support only; verify with the provider before disputing.