EDI Resource Center

Health Level Seven (HL7)

Health Level Seven, or HL7, is a set of international standards for transferring clinical and administrative data between software applications used by healthcare providers. These standards focus on the application layer, which is "layer 7" in the International Organization for Standards (ISO) model of standardization.

Hospitals and other healthcare providers typically have a variety of disparate computer systems used for everything from billing records to patient tracking. HL7 helps all of these systems communicate, or interface, when they receive, or need to receive, new information.

HL7 specifies a variety of flexible standards, guidelines and methodologies that healthcare systems can use to communicate with each other, share information and process data in a uniform, consistent way. This information exchange has helped make medical care less geographically isolated and variable.

Industries Using HL7

  • Healthcare
  • Hospitals and clinics

Types of HL7 Transactions

HL7 provides standardization for hundreds of healthcare events in hospital systems. A small sample of these transactions includes:

  • Patient admit notifications
  • Patient transfers
  • Patient discharges
  • Clinical study information
  • Master files
  • Pharmacy orders
  • Diet orders


  • Created in 1987 along with the founding of Health Level Seven International
  • Continuously updated and maintained

Governing Body

Founded in 1987, Health Level Seven International (HL7) is a not-for-profit, ANSI-accredited standards developing organization dedicated to providing a comprehensive framework and related standards for the exchange, integration, sharing, and retrieval of electronic health information that supports clinical practice and the management, delivery and evaluation of health services. HL7 is supported by more than 1,600 members from over 50 countries, including 500+ corporate members representing healthcare providers, government stakeholders, payers, pharmaceutical companies, vendors/suppliers, and consulting firms.

HL7 Transactions List