If you have health insurance, you've probably received a document titled Explanation of Benefits, or EOB — usually stamped with the confusing line "This is not a bill." So what is it, and what are you supposed to do with it? Here's the plain-English version.
What an EOB actually is
An EOB is a summary your insurance company sends after a doctor or hospital files a claim. It's not a request for payment — it's a receipt showing how the claim was processed and how much, if anything, you may owe. The real bill comes separately, from the provider.
The five numbers that matter
Nearly every EOB, no matter how cluttered, comes down to five figures. Read them in this order:
- Amount billed — what the provider charged. This number is almost always inflated and rarely what anyone actually pays.
- Allowed amount — the discounted rate your insurer's network has negotiated. This is the number that matters.
- Plan paid — what your insurance covered.
- Patient responsibility — your share (deductible + copay + coinsurance). This is the only number you might owe.
- Not covered — anything the plan didn't pay, with a reason code.
"This is not a bill" — so when do I pay?
You don't pay the EOB. You wait for the provider's actual bill, then compare it to the EOB. The bill should never be more than the "patient responsibility" line. If it is, that's a red flag — call the provider's billing office.
Three things to check every time
- Does the bill match the EOB? If the provider bills you more than your patient responsibility, push back.
- Any denied lines? Look for reason codes like "needs prior authorization" or "out of network." Denials are often fixable through an appeal — usually within 180 days.
- Duplicate or surprise charges? Request an itemized bill; duplicate charges are common.
The bottom line
An EOB looks intimidating, but it's really just: here's what was charged, here's what we covered, here's your share — don't pay until the real bill matches this.
Still staring at an EOB that doesn't make sense? Plainly is a free Chrome extension that explains your EOB, medical bill, or any confusing document in plain English — right on the page. Your documents are never stored.