Understanding EOBs and ERAs for ABA Practices

EOB vs. ERA: What's the Difference?

An Explanation of Benefits (EOB) is a document sent by the payer to the provider (and patient) explaining how a claim was processed. An Electronic Remittance Advice (ERA / 835 transaction) is the electronic version of the EOB, transmitted via EDI to the clearinghouse and practice management system. ERAs enable automated payment posting.

Reading an ERA: Key Fields

• Check/EFT Number: The payment reference — use this to match the bank deposit
• Payment Date: Date the check was issued or EFT initiated
• Claim Control Number: Payer's internal tracking number for the claim
• Billed Amount: Your submitted charge
• Allowed Amount: The contracted rate
• Contractual Adjustment (CO-45): Difference between billed and allowed — write off
• Patient Responsibility (PR-1, PR-2, PR-3): Deductible, coinsurance, copay to collect from patient
• Paid Amount: What the payer sent

Reconciling ERA to Bank Deposit

After posting ERA payments in your system, reconcile against the actual bank deposit:

1. Match the ERA check/EFT number to the bank transaction reference
2. Verify the bank deposit amount equals the ERA payment amount
3. If amounts differ, investigate — payer may have combined multiple ERA payments or deducted prior overpayments
4. Document reconciliation; flag any unreconciled differences for follow-up

ERA Error Codes (CARC/RARC)

ERAs include Claim Adjustment Reason Codes (CARC) and Remittance Advice Remark Codes (RARC). CARCs explain the payment adjustment; RARCs provide supplemental detail. See our CARC Reference Guide for details on specific codes.