After a doctor visit, your insurer sends an Explanation of Benefits (EOB). It’s full of columns and codes, and it often says “This is not a bill” — so many people throw it away. That’s a mistake: your EOB is the best tool you have for catching billing errors and knowing what you really owe.
Key takeaways
- An EOB explains how your insurer processed a claim. It is not a bill.
- The most important line is “Patient responsibility” (or “You may owe”).
- Your provider’s bill should match it. If it doesn’t, call before paying.
- Keep EOBs until the claim is settled — and for HSA records.
The parts of an EOB
| Term on your EOB | What it means |
|---|---|
| Patient / member | Who received the care (check it’s the right person) |
| Provider | The doctor or facility, and whether they’re in network |
| Date of service | When you got the care |
| Service description / code | What was done (e.g., office visit, lab test) |
| Amount billed / charged | The provider’s full list price — often much higher than anyone pays |
| Allowed amount / plan discount | The negotiated price your plan agreed to; the discount is the difference |
| Plan paid | What your insurer paid the provider |
| Deductible / copay / coinsurance | How your share was calculated |
| Not covered / denied | Amounts the plan didn’t pay, with a reason code |
| Patient responsibility | What you may owe the provider |
A sample EOB, decoded
Suppose you had an MRI at an in-network imaging center. Your EOB shows:
- Amount billed: $2,400
- Plan discount: $1,550 → allowed amount $850
- Applied to deductible: $500 (the rest of your deductible)
- Coinsurance (20% of the remaining $350): $70
- Plan paid: $280
- Patient responsibility: $570
If the imaging center later sends you a bill for $2,400 or $1,000, that’s a red flag — you should owe $570. Call the provider and reference the EOB. (Need a refresher? See how deductibles and coinsurance work.)
Red flags to watch for
- Services you didn’t receive — possible error or even medical identity theft. Call your insurer.
- An in-network provider listed as out-of-network.
- A denial code — the claim may need a corrected code, more information or an appeal.
- Preventive care charged to your deductible — it may have been coded as diagnostic.
- The same service listed twice.
What to do with your EOB
- Match each provider bill to its EOB before paying.
- If a claim was denied, call your insurer to find out why. You can appeal.
- Track your deductible and out-of-pocket progress — many EOBs show year-to-date totals.
- Save EOBs with receipts if you’ll reimburse yourself from an HSA or FSA.
Frequently asked questions
Why is the “amount billed” so high?
Providers set list prices (“chargemaster” rates) far above what insurers actually pay. Your share is based on the allowed amount, not the billed amount — one of the big benefits of staying in network.
I got an EOB but no bill. Do I owe anything?
If “patient responsibility” is above $0, you’ll probably get a bill later. Wait for it rather than paying the EOB amount to your insurer.
Can I get EOBs online?
Yes. Most insurers post EOBs in your online account or app, often days before paper copies arrive. You can usually switch to electronic-only delivery.
How long should I keep EOBs?
At least until the claim is paid and the provider’s bill is settled. If you use an HSA, keep them with your receipts as long as you might need to prove qualified expenses.
Sources: HealthCare.gov glossary; CMS consumer resources. Example numbers are illustrative. For education only — not insurance advice. Last reviewed October 2026.
