An EOB is your insurer's statement showing what a provider charged, what insurance allowed and paid, and what you may owe. It is not a bill — and comparing it to the actual bill is how billing errors get caught.
After a medical visit, the EOB arrives from your insurance company, often before the provider's bill. It shows the billed amount, the negotiated "allowed" amount, what insurance paid, and the patient-responsibility number. That last figure is what the provider should bill you — when the bill doesn't match the EOB, one of them is wrong, and it's frequently the bill. EOBs are also where denials first appear, with reason codes that tell you exactly what to appeal. Most billing disputes are won by people who kept and compared their EOBs.
Check whether the provider was in-network, whether the deductible applied, and whether the claim was coded correctly. Coding errors are common and providers can resubmit.
It can mean the provider never billed your insurance. Don't pay cash prices for covered care — ask the provider to submit the claim, then wait for the EOB.
Upload the bill and the EOB together — Main AI reconciles them, flags mismatches and questionable charges, and drafts the dispute letter.
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