Claim attachments

Claim attachments are additional documents that help justify or validate a claim. They're typically required when the claim alone doesn't provide enough information for the payer to make a decision, such as when a procedure is unusual, high-cost, or uses an unlisted code.

Attachments can include medical records, treatment plans, radiographs, photographs, itemized bills, and letters from providers - the type required for each claim depends on the services listed and the payer's rules. For example, a claim for a dental crown may require X-rays, while a claim for a surgery may require an operative report.

You can submit unsolicited 275 claim attachments for professional and dental claims in either JSON or X12 EDI format. Attachments for institutional claims aren't supported.

Transaction enrollment

Some payers require enrollment before allowing providers to submit 275 claim attachments. This enrollment process is separate from the transaction enrollment process for 837 claims.

The Payer Network lists which payers require transaction enrollment for 275 claim attachments. Visit transaction enrollment for details about the transaction enrollment process.

JSON submission

You can submit unsolicited claim attachments through Stedi JSON APIs. Submitting claim attachments in JSON requires three steps:

1

Create the claim attachment.

Call the Create Claim Attachment (275) JSON endpoint to receive a pre-signed URL that you can use to upload the attachment file to Stedi.

The response also contains an attachmentId that you'll include in the claim submission.

2

Upload the attachment file.

Use a PUT request to upload the attachment file to the pre-signed URL (uploadUrl) in the response. The request must include a Content-Type header that matches the MIME type you specified for the attachment file.

The following example shows how to upload a JPEG attachment:

curl --request PUT \
  --url "<uploadUrl>" \
  --header "Content-Type: image/jpeg" \
  --upload-file /path/to/file.jpeg

We recommend limiting attachments to 64MB each, but some payers may have different size requirements. When in doubt, check the payer's documentation to determine their specific limits. Stedi stores uploaded files for 45 days. After that, you must reupload the attachment file before you can submit it to the payer.

3

Submit the claim and attachment information.

Call one of the following claim submission endpoints:

• Professional Claims JSON
• Dental Claims JSON

You must include specific properties in your request to identify the attachment and tell Stedi which attachment file to use. These properties are attachmentReportTypeCode, attachmentTransmissionCode, and attachmentId.

Stedi sends the claim and the claim attachment to the payer and then returns summary information about the claim submission.

The payer processes the claim and attachment together, and sends back 277CA and 835 ERA responses.

X12 EDI submission

You can submit unsolicited claim attachments in X12 EDI format through the API or SFTP. We recommend this approach when you have an existing system that generates X12 EDI files and you want to send them through Stedi.

With X12 EDI submissions, you don't need to upload the attachment file to Stedi first - you can send the entire 275 transaction directly to the payer.

API

1

Submit the claim.

Call one of the following endpoints:

• Professional Claims Raw X12
• Dental Claims Raw X12

In addition to the claim information, you must include specific elements in either Loop 2300 or Loop 2400 (professional claims only) to identify the attachment. These elements are PWK01, PWK02, and PWK06.

2

Submit the attachment.

Call the Submit Claim Attachment (275) X12 EDI endpoint. Stedi sends the 275 transaction to the payer and returns summary information about the submission.

• Payer ID: You must submit a payer identifier in Loop 1000A NM109 so Stedi can route the attachment to the correct payer. This identifier must be a payer ID or payer ID alias listed in the Payer Network. For example, you could use 60054, HPQRS, AETNA, or any other listed payer ID alias for Aetna.
• The size limit for attachments submitted in a single API request is 6MB. If you need to submit larger attachment files, you must submit them through Stedi SFTP or the JSON endpoints.

Once received, the payer processes the claim and attachment together, and sends back 277CA and 835 ERA responses.

SFTP

SFTP submission is ideal if you have attachments that are larger than 6MB. We recommend limiting attachments to 64MB each, but some payers may have different size requirements. When in doubt, check the payer's documentation to determine their specific limits.

1

Submit the claim.

Submit an 837 professional or dental claim to the payer through Stedi SFTP.

You must include specific elements in either Loop 2300 or Loop 2400 (professional claims only) to identify the attachment. These elements are PWK01, PWK02, and PWK06.

2

Submit the attachment.

Submit a 275 claim attachment to the payer through Stedi SFTP.

You must submit a payer identifier in Loop 1000A NM109 so Stedi can route the attachment to the correct payer. This identifier must be a payer ID or payer ID alias listed in the Payer Network. For example, you could use 60054, HPQRS, AETNA, or any other listed payer ID alias for Aetna.

Once received, the payer processes the claim and attachment together, and sends back 277CA and 835 ERA responses.

Reference attachments in a claim

To submit an unsolicited claim attachment, you must submit a claim that references the attachment(s) in the appropriate location.

Attachment level

You can specify attachments that relate to the entire claim or to a specific service line.

• Entire claim: For professional and dental claims, you can specify claim-level attachments in the claimInformation.claimSupplementalInformation.reportInformation object or the claimInformation.claimSupplementalInformation.reportInformations[] array (multiple attachments). This object corresponds to segment PWK in Loop 2300.

  API reference docs: professional | dental

• Service line: For professional claims, you can specify service line attachments in the claimInformation.serviceLines.serviceLineSupplementalInformation object array. This object corresponds to segment PWK in Loop 2400.

  API reference docs: professional

Required properties

Both claim and service line attachments require the following properties to inform the payer that an attachment will follow the claim submission.

JSON property	X12 EDI	Description
attachmentReportTypeCode	PWK01	This code identifies the type of report or document you plan to submit as an attachment. Visit Code lists for a complete list of valid codes.
attachmentTransmissionCode	PWK02	Set to EL when submitting attachments through Stedi. This property indicates the attachment will be sent in a separate, electronic 275 transaction.

You must also include one of the following properties, depending on your use case.

JSON property	X12 EDI	Description
attachmentControlNumber	PWK06	A unique identifier for the attachment. The payer uses this value to match the attachment to the claim. We recommend using a ULID or UUID of up to 50 characters. X12 EDI submissions: This property is required. JSON submissions: Only include this property when you aren't submitting the attachment file through Stedi's API. For example, you submitted the attachment directly through a payer's portal.
attachmentId	-	The attachment ID you received in the Create Claim Attachment (275) JSON response. It tells Stedi which file to use when generating the 275 transaction for the payer. This property is required if you're submitting attachments through a JSON endpoint.

Solicited vs. unsolicited attachments

There are two types of claim attachments:

• Solicited: The payer requests attachments for a submitted claim in a Request for Additional Information (277 RFA) transaction. In these cases, you must submit the attachment(s) in a separate 275 transaction that references the 277 RFA.
• Unsolicited: The provider proactively sends attachments at their discretion without a prior request from the payer. In these cases, you must reference the attachment(s) in the claim submission.

You can only submit unsolicited claim attachments through Stedi APIs and SFTP. Check the Payer Network to determine which payers support attachments.

Payer responses

The payer processes claims and claim attachments together. When you submit a claim attachment, you'll receive the same 277CA and 835 ERA responses for the claim as you would for a regular claim submission.

If a claim is rejected, pended, or denied due to issues with attachments, you'll likely receive error codes in the 277CA response that indicate the issue. However, the exact error codes used depend on the payer's system and how they handle attachments.

Concurrency limit

Claim attachment endpoints share a concurrency pool with other claim endpoints. For more information, visit Concurrency limits.