EDI 835 vs 837: What’s the Difference?

An EDI 837 is a healthcare claim that a provider sends for payment. An EDI 835 is the remittance advice a payer returns after processing claims. This guide compares the two file types with examples and practical tips.

Quick Table of Contents

TL;DR (fast answer)

EDI 837

Claims go out

An EDI 837 is a healthcare claim submission file. Providers send it to payers or clearinghouses to request payment.

  • Think: “Here’s what we’re billing you for.”
  • Contains diagnoses, procedures, charges, providers, subscribers, and service lines.
  • Forms: 837P (professional), 837I (institutional), 837D (dental).
EDI 835

Payments come back

An EDI 835 is an ERA (Electronic Remittance Advice) file. Payers send it back to explain what they paid (or denied) for each claim line.

  • Think: “Here’s what we paid, and why.”
  • Contains paid amounts, adjustments, denial reasons, and patient responsibility.
  • Used for posting payments and reconciling claims.
If you ever forget: 837 = claim, 835 = payment/remittance.

What is an EDI 837 file?

The ASC X12 837 transaction is the industry standard for sending healthcare claims electronically. A provider (doctor, hospital, lab, etc.) sends an 837 to a payer (insurance company, Medicaid, Medicare, etc.) to request reimbursement.

What’s inside an 837?

An 837 is basically a structured “billing packet.” It includes:

  • Patient/Subscribers (member IDs, demographics)
  • Provider info (NPI, taxonomy, billing/rendering)
  • Claim header (claim control numbers, dates)
  • Service lines with procedure codes (CPT/HCPCS), modifiers, charges, and units
  • Diagnosis codes (ICD-10)

Short 837 example

Don’t worry about every element yet — just notice the CLM claim header and SV1 service line:

CLM*26463774*100***11:B:1*Y*A*Y*I~
HI*ABK:K352~
SV1*HC:99213*100*UN*1***1~
DTP*472*D8*20250110~
  • CLM = claim header (claim ID, total charges, place of service)
  • HI = diagnoses
  • SV1 = professional service line (procedure + charge)
  • DTP = service date

837P vs 837I vs 837D

  • 837P (Professional) — doctor/clinic claims. Uses segments like SV1.
  • 837I (Institutional) — hospital/facility claims. Uses SV2 and revenue codes.
  • 837D (Dental) — dental claims. Specialized dental loops and tooth data.

What is an EDI 835 file?

The ASC X12 835 transaction is the standard for Electronic Remittance Advice (ERA). After a payer processes an 837 claim, they reply with an 835 telling you what they paid and why.

What’s inside an 835?

An 835 contains:

  • Payment totals (EFT/check amounts)
  • Claim payment results per claim and per service line
  • Adjustments / denials with reason codes
  • Patient responsibility amounts (copay/deductible/coinsurance)

Short 835 example

Look for CLP claim payment and CAS adjustments:

BPR*I*80*C*ACH*CCP************20250115~
TRN*1*1234567890*9876543210~
CLP*26463774*1*100*80*20*MC*12345~
CAS*PR*1*20~
SVC*HC:99213*100*80~
DTM*472*20250110~
  • BPR = payment method and total paid
  • TRN = trace number (ties to EFT/check)
  • CLP = claim paid/denied breakdown
  • CAS = adjustments (group + reason code + amount)
  • SVC = service line paid
  • DTM = service date
In plain English: an 835 is the payer’s “receipt” for your 837 claim.

835 vs 837 side-by-side comparison

Feature 837 (Claim) EDI 835 (Remittance/ERA)
Direction Provider → Payer / Clearinghouse Payer → Provider
Purpose Submit claim for payment Explain payment/denial for submitted claim
When used Before adjudication After adjudication
Key segments CLM, HI, SV1/SV2, NM1, DTP BPR, TRN, CLP, CAS, SVC, DTM
Contains Diagnosis codes, procedures, charges, provider/subscriber details Paid amounts, adjustment reasons, patient responsibility
Common outputs Claim line table, diagnosis list, provider/member identifiers Payment posting table, denial/adjustment summary
Other names X12 837P / 837I / 837D X12 835 / ERA / Remit

Common segments you’ll see in each file

EDI files are built from segments separated by a terminator (often ~). Each segment begins with a 2–3 letter tag.

Common 837 segments

  • ISA / GS / ST — envelope headers
  • NM1 — names (patient, subscriber, provider)
  • CLM — claim header (claim ID, total charge, POS)
  • HI — diagnosis codes
  • SV1 — service line in 837P
  • SV2 — service line in 837I
  • DTP — dates

Common 835 segments

  • BPR — payment total and method
  • TRN — payment trace/check number
  • N1 / N3 / N4 — payer & payee info
  • CLP — claim payment status
  • CAS — adjustments / denials (deductible, coinsurance, etc.)
  • SVC — service line paid/allowed amounts
  • DTM — service/receipt dates

Why CLP and CAS matter in 835

If you’re doing payment posting or denial analysis, CLP tells you what happened to the claim overall, and CAS tells you why money moved.

  • CLP03 = total charge
  • CLP04 = amount paid
  • CLP05 = patient responsibility
  • CAS*PR = patient responsibility adjustments
  • CAS*CO = contractual obligations
  • CAS*OA = other adjustments

Why convert 835/837 to CSV or Excel?

Raw EDI is great for computers, but rough for humans. Converting to CSV/Excel lets you:

  • Open files in Excel and filter/sort by claim, member, procedure, denial reason, etc.
  • Post payments faster (835 → readable payment tables)
  • Audit claims before sending (837 → clear claim line review)
  • Bulk analyze denials and patient responsibility trends
  • Share with teams who don’t read raw X12
Want to see your own files in a readable format?
Use the client-side EDI 835/837 to CSV & Excel converter. Tip: Supported browser-local processing reduces the need to transmit EDI file contents to the application server.
Compare all EDI tools to choose a viewing, parsing, conversion, or validation workflow.

FAQ: common beginner questions

Can an 837 have multiple claims?

Yes. An 837 usually includes many claims, each with its own claim loop (2300) and service line loop (2400).

Does every 837 get an 835 back?

Typically yes, unless the claim is rejected before adjudication or paid through a different reporting channel. For most payers, every accepted 837 yields an 835 response.

Why are my 835 adjustments confusing?

Because a single claim can have multiple CAS segments. Each CAS includes a group code (PR/CO/OA) and one or more reason codes with amounts.

What’s the easiest way to read EDI files?

Inspect the file in the Client-Side EDI Viewer, or convert it to CSV/Excel. Once tabular, you can filter by claim ID, CPT, denial reason, paid amount, and more.