# Introducing Stedi's Institutional Claims X12 API endpoint

> You can now submit 837I institutional claims as X12 EDI using the new Institutional Claims X12 API endpoint. It's ready for fast, drop-in integration.

Published Sep 10, 2025

Updated Nov 10, 2026

Category: Products

You can now submit 837I institutional claims as X12 EDI using the new [Institutional Claims X12 API endpoint](https://www.stedi.com/docs/healthcare/api-reference/post-healthcare-institutional-claims-raw-x12).

Most Stedi customers submit 837I claims using our [JSON-based Institutional Claims endpoint](https://www.stedi.com/docs/healthcare/api-reference/post-healthcare-institutional-claims). JSON is familiar and easy to work with. You can build an integration faster.

But if you already work with X12, converting to JSON wastes time. The new endpoint accepts X12 directly.

Previously, X12 submissions of 837I claims required [SFTP](https://www.stedi.com/docs/healthcare/submit-claims-sftp-connection). With SFTP, you have to wait for files to get errors or validation. With the API, you get instant responses. Development is faster, and debugging is easier.

## Use the Institutional Claims X12 endpoint

To use the endpoint, send a `POST` request to the `https://healthcare.us.stedi.com/2024-04-01/change/medicalnetwork/institutionalclaims/v1/raw-x12-submission` endpoint. Include an [837I X12](https://portal.stedi.com/app/guides/view/hipaa/health-care-claim-institutional-x223a2/01JBHW2YXMN2F9KXK2PS0BFP9F) payload in the request body’s `x12` field:

```bash
curl --request POST \
  --url "https://healthcare.us.stedi.com/2024-04-01/change/medicalnetwork/institutionalclaims/v1/raw-x12-submission" \
  --header "Authorization: <api_key>" \
  --header "Content-Type: application/json" \
  --data '{
    "x12": "ISA*00*          *00*          *ZZ*001690149382   *ZZ*STEDITEST      *240630*0847*^*00501*000000001*0*T*>~GS*HC*001690149382*STEDITEST*20240630*084744*000000001*X*005010X223A2~ST*837*3456*005010X223A2~BHT*0019*00*0123*20061123*1023*CH~NM1*41*2*PREMIER BILLING SERVICE*****46*TGJ23~PER*IC*JERRY*TE*7176149999~NM1*40*2*AETNA*****46*AETNA~HL*1**20*1~NM1*85*2*TEST HOSPITAL*****XX*1234567890~N3*123 HOSPITAL ST~N4*NEW YORK*NY*10001~REF*EI*123456789~HL*2*1*22*1~SBR*P********CI~NM1*IL*1*DOE*JOHN****MI*123456789~NM1*PR*2*AETNA*****PI*AETNA~HL*3*2*23*0~PAT*19~NM1*QC*1*DOE*JOHN~N3*123 MAIN ST~N4*NEW YORK*NY*10001~DMG*D8*19800101*M~CLM*26403774*150***11>B>1*Y*A*Y*I~DTP*472*D8*20240101~REF*D9*17312345600006351~NM1*82*1*SMITH*JANE****XX*1234567890~PRV*AT*PXC*207Q00000X~LX*1~SV2*0450*HC>99213*150****1~DTP*472*D8*20240101~SE*29*3456~GE*1*000000001~IEA*1*000000001~"
  }'
```

Stedi validates the EDI and sends the claim to the payer.

The endpoint returns a response from Stedi in JSON. The JSON contains information about the claim you submitted and whether the submission was successful:

```jsonc
{
  "claimReference": {
    "correlationId": "01J1M588QT2TAV2N093GNJ998T",
    "formatVersion": "5010",
    "patientControlNumber": "26403774",
    "payerId": "AETNA",
    "rhClaimNumber": "01J1M588QT2TAV2N093GNJ998T",
    "serviceLines": [
      {
        "lineItemControlNumber": "1"
      }
    ],
    "timeOfResponse": "2024-07-10T22:05:32.203Z"
  },
  "controlNumber": "000000001",
  "httpStatusCode": "200 OK",
  "meta": {
    "traceId": "b727b8e7-1f00-4011-bc6e-e41444d406d8"
  },
  "payer": {
    "payerID": "AETNA",
    "payerName": "Aetna"
  },
  "status": "SUCCESS",
  "tradingPartnerServiceId": "AETNA"
}
```

For complete details, check out the [Institutional Claims (837I) Raw X12 API reference](https://www.stedi.com/docs/healthcare/api-reference/post-healthcare-institutional-claims-raw-x12).

## Get started

The [Institutional Claims X12 endpoint](https://www.stedi.com/docs/healthcare/api-reference/post-healthcare-institutional-claims-raw-x12) is available on all paid Stedi plans.

To get started with Stedi, [sign up](https://portal.stedi.com/auth/sign-up-intent) for a free sandbox account. It takes less than two minutes. No credit card is required.

When you're ready, upgrade to production on our [pay-as-you-go plan](https://www.stedi.com/pricing). There are no monthly minimums or setup fees. You only pay for the transactions you use.