How to read your Explanation of Benefits (EOB)
An EOB is a math worksheet, not a bill. Learn what each column means and how to spot errors before you pay your provider.
An Explanation of Benefits (EOB) is a statement your insurer sends after processing a claim. It is not a bill — it shows what was billed, what the plan paid, and what you owe. Compare every EOB against the bill from the provider before paying.
The columns you'll see
- Amount billed — The provider's sticker price. Often inflated, especially for out-of-network care.
- Allowed amount (or 'plan allowed') — The maximum the plan considers reasonable. This is the number cost-sharing is calculated from.
- Plan discount — The difference between billed and allowed. For in-network providers, this is the negotiated discount you don't have to pay.
- Plan paid — What the insurer paid the provider.
- Your responsibility — Deductible, copay, coinsurance, and any non-covered amount you owe.
- Remark codes — Numbered codes explaining why a portion was denied, adjusted, or paid at a different rate.
How to verify your EOB
- Match the date and provider to your records
Check that the visit date and provider name match what you remember. Mismatches can signal billing errors or fraud.
- Confirm the procedure makes sense
Glance at the procedure description. If you went in for a strep test and see codes for a knee MRI, something is wrong.
- Check the network status
If you're sure the provider was in-network but the EOB applied out-of-network rates, call the insurer with the provider directory in hand.
- Add up your responsibility
Deductible + copay + coinsurance + non-covered = your responsibility. The math should add up exactly.
- Compare to the provider's bill
Wait for the provider's bill and check that what they're asking matches your responsibility column on the EOB. If not, call both — usually the provider is wrong.
FAQ
- Why is my EOB labeled 'This is not a bill'?
Because it's a record of how the insurer processed the claim, not a request for payment. Your actual bill comes from the provider.
- What does remark code N362 / CO-45 / PR-1 mean?
Every code is explained in the legend on the EOB itself. If something doesn't make sense, call the customer service number on the EOB — they can interpret each code.
- How long should I keep EOBs?
At least one year, and longer for major procedures or anything you might appeal. For HSA-eligible expenses, keep them with your tax records.