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Electronic Data Interchange - An FAQ for MassHealth providers

Learn about the Electronic Data Interchange (EDI).

What is EDI?

EDI stands for Electronic Data Interchange, a process that facilitates the exchange of electronic files. The term EDI is the industry standard terminology for electronic transactions.

Where can I get the EDI specifications for my MassHealth electronic claims?

The EDI specifications for MassHealth electronic claims are based on the following documents:

An Implementation Guide is provided for each transaction. It is accompanied by a MassHealth Companion Guide and the appropriate billing instructions to guide providers on the submission of transactions to MassHealth.

  • ASC X12 Implementation Guide
  • Companion Guides
  • Billing Instructions
  • Provider bulletins
  • Message texts
  • MassHealth-specific documents can be found at www.mass.gov/MassHealth.
  • EDI Testing

How do I know that my claims file was received and accepted by MassHealth?

MassHealth will generate a 999 acknowledgement. The 999 will contain data indicating the number of transaction sets received in your file, and their status. A status of "A" in IK501 indicates that the transaction set was accepted; a status of "R" indicates that the transaction set was rejected. The AK9 segment conveys the overall compliance of the file; in addition to statuses “A” and “R”, it may include a status of “P” for partially accepted in AK901. Only rejected transactions need to be corrected and resubmitted. Please comply with MassHealth billing guidelines to ensure timely processing of your transaction.

Verifying that a 999 is downloaded and reviewed for each submitted file is the responsibility of the submitter. The 999 should be downloaded from the Provider Online Service Center (POSC). The 999 can also be obtained via the healthcare transaction service (HTS) formerly known as system-to-system.

The 999 should be available for download no later than one business day of receipt of your file. If you cannot download a 999 within that time frame, you should contact us at 1-800-841-2900 for assistance.

  • Within 2 to 24 hours after submitting a 276 request, MassHealth will generate a 999 acknowledgment file if the 276 passes pre-compliance.
  • The 999 will contain data indicating the number of transaction sets received in the 276 file and their status.
    • The AK9 segment will give the overall compliance of the file.
    • The IK501 data element will give a status of the transaction set.
  • Providers must download and review the 999 from the Provider Online Service Center (POSC).
    • A status of “A” in the AK901 indicates that the file was accepted.
    • A status of “R” in the AK901 indicates that the file was rejected.
    • A status of “P” in the AK901 indicates that the file was partially accepted.
    • A status of “R” in the IK501 indicates that the transaction set was rejected.
  • If the file was rejected or partially rejected, providers must correct the errors and resubmit the file.
  • Please comply with MassHealth billing guidelines to ensure timely processing of your transaction.
  • Contact EDI@MAHealth.net for assistance in reading the 999 file or correcting errors.

What is a 999?

The 999 is a HIPAA-defined transaction that indicates acknowledgement of receipt and status of each functional group in an EDI X12 File containing transactions.

I didn't receive a 999, what do I do?

If you haven't received a 999 within 24 hours after submission of your 270/271, 276/277 or 837 file, you may contact us at (800) 841-2900 to inquire about the status.

How do I interpret the 999 transaction information?

MassHealth has created a helpful billing tips flier (see link below) to explain how to read your 999. For more information, you can review the 999 Transaction Implementation Guide, the HIPAA regulations and implementation guides can be found online at http://www.wpc-edi.com.

Additional Resources

What documents should I use in order to determine how to submit healthcare transactions to MassH

You should have a copy of the Companion Guides that are specific to your transaction type (i.e., 270/271, 276/277, 820, 834 Inbound, 834 Outbound, 837I, and 837P).

  • MassHealth Connectivity Companion Guide

Please contact us at (800) 841-2900 for a copy of the guide or email at EDI@mahealth.net

What HIPAA transactions does MassHealth support?

The following transactions are supported:

  • 270/271: Health Care Eligibility/Benefit Inquiry and Information Response
  • 276/277: Health Care Claim Status Request and Response
  • 820: Health Care Premium Payment
  • 834: Health Care Benefit Enrollment and Maintenance Outbound
  • 835: Health Care Payment/Advice
  • 837I: Health Care Claim: Institutional
  • 837P: Health Care Claim: Professional

What is a companion guide and how can I get one?

A companion guide is used in conjunction with the ASC X12 HIPAA Implementation Guide. It details how a specific payer interprets the data elements, and the information they require for processing claims.

For more information and to obtain a copy of the MassHealth Companion Guides, please visit the MassHealth HIPAA Companion Guides page.

What is a MassHealth Trading Partner Agreement and do I need one?

A Trading Partner Agreement (TPA) is "an agreement between the covered entities (HIPAA Regulations: 45 CFR Part 162.915) that are engaged in EDI transactions. TPAs specify the rules and responsibilities of each party involved in the transaction in addition to indicating requirements such as communications and financial arrangements (e.g., which entity is responsible for telecom costs).

All MassHealth participating providers are required to complete and submit a TPA even if they do not plan to submit claims electronically. You can download the MassHealth Trading Partner Agreement by using the link below.

Additional Resources

How do I arrange to receive the 835 transaction?

Contact us at (800) 841-2900 or e-mail EDI@mahealth.net to coordinate the necessary setup for receipt of the 835 transaction. Depending on whether you are a provider using a clearinghouse or billing intermediary, a provider submitting your own claims, or an organization managing multiple providers, there are unique sets of information that are required to complete the registration process.

What documents should I have available for successful 835 transaction processing?

The management of your 835 transaction processing will be specific to your organization. Your IT staff may process the 835 file and use it for posting, or you may be responsible for interpreting claim results.

The following are the reference tools available to successfully manage your 835 transaction processing. Depending on how your organization manages the 835 processing, you may need to have a copy of the following documents that are specific to your transaction type:

  • 835 Implementation Guide
  • 835 MassHealth Companion Guide
  • 837 Implementation Guide
  • 837 MassHealth Companion Guide
  • The MassHealth provider manual specific to your provider type
  • All MassHealth bulletins that have been issued for your provider type
  • Copy of related MassHealth Remittance Advice, available for download from the POSC
  • CARC & RARC Code List (see Claim Adjustment Reason Code/ Remittance Advice Remark Code link below)

For a copy of the MassHealth Companion Guides, contact us at (800) 841-2900 or email your inquiry to EDI@mahealth.net.

Additional Resources

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