When a payer processes a claim, it returns a statement explaining what it paid, adjusted, and denied. Learning to read it is one of the most practical revenue skills a practice can build, because that is where denials and underpayments hide.
EOB vs. ERA: same story, two formats
An Explanation of Benefits (EOB) is the human-readable statement of how a claim was handled. An Electronic Remittance Advice (ERA), the EDI 835 transaction, is the electronic equivalent that posts to your billing system automatically. Both tell you the same thing; the ERA just does it at scale.
The key fields to read
Billed amount
What you charged for the service. On its own it tells you little, what matters is what the payer allowed and paid against it.
Allowed amount
The maximum the payer recognizes for the service under your contract. Compare this to your fee schedule to confirm the payer is honoring the contracted rate.
Paid amount
What the payer actually paid. If it is less than the allowed amount minus patient responsibility, dig into why.
Patient responsibility
Deductible, copay, and coinsurance amounts the patient owes. This is what you bill the patient after the payer pays.
Adjustments and reason codes
Any reduction is explained by standardized codes: CARCs (Claim Adjustment Reason Codes) and RARCs (Remittance Advice Remark Codes). These are the most important part of the remittance, they tell you whether an amount was a contractual write-off, a denial, or an error you can appeal.
What to look for every time
- Denials: any line paid at zero with a denial reason code, work and appeal the recoverable ones promptly.
- Underpayments: paid amount below your contracted allowed amount, a common, easily missed leak.
- Unexpected adjustments: reductions you did not anticipate, which may signal a coding or contract issue.
- Patient balances: confirm the responsibility amounts before billing the patient.
Turn remittances into recovered revenue
Reading remittances is not just bookkeeping, it is where underpayments and appealable denials are found. Practices that reconcile every ERA against their contracts catch money that would otherwise disappear into write-offs. That reconciliation is part of what we do for the practices we serve.
Want a second set of eyes on where your payments are falling short? Request a free revenue review, or brush up on terms in our RCM glossary.