Technical / EDI
835 ERA Explained: How Electronic Remittance Advice Works
The 835 is the EDI electronic remittance advice (ERA) a payer sends to explain how a claim was adjudicated: payments, adjustments, and denial codes (CARC/RARC). It lets payments post automatically with line-level reconciliation, far faster than manual EOB entry.
The 835 is the payment side of EDI. Where the 837 sends a claim out, the 835 comes back telling you exactly how each claim and line was paid, adjusted, or denied, and it is what makes automated payment posting possible.
What is an 835?
The 835 is the X12 electronic remittance advice. It carries the payer's adjudication decision for each claim: the paid amount, contractual adjustments, patient responsibility, and any adjustment reason codes (CARC) and remark codes (RARC).
835 vs EOB
The 835 is the machine-readable version; the EOB (explanation of benefits) is the human-readable version of the same information. Posting from an 835 can be automated line by line, while posting from paper EOBs is manual and slower.
How auto-posting works
Posting software reads the 835, matches each payment to the right claim and service line, posts the paid amount and contractual adjustment, and routes denials (by their CARC/RARC) into the denial workflow. This reconciliation is where underpayments and denials surface.
Why the codes matter
The CARC and RARC codes on the 835 drive everything downstream: they tell you why a line was adjusted or denied, which is the starting point for denial management and for spotting underpayments against the fee schedule.
How MedXFlow AI agents handle this
MedXFlow's AI agents work directly with the EDI transactions behind this - 270/271, 837, 835, 276/277 and 278 - and fall back to payer-portal automation where a transaction is not supported, so the workflow runs whatever channel each payer uses.
Related resources
Frequently asked questions
What is the difference between an 835 and an EOB?
They contain the same adjudication information. The 835 is the electronic, machine-readable remittance used for automated posting; the EOB is the human-readable version.
How does the 835 help denials?
It carries the CARC and RARC codes that explain each adjustment or denial, which is the starting point for triaging and working denials and for detecting underpayments.