HIPAA Simplified


The Health Insurance Portability and Accountability Act of 1996 (HIPAA) required the Secretary of Health and Human Services (HHS) to adopt standards for the following identifiers: 

  • Employer Identification Number (EIN)
  • Health Plan Identifier (HPID)
  • National Provider Identifier (NPI)
  • Unique Patient Identifier (UPI)

Employer Identification Number (EIN)

HHS issued the Health Insurance Reform: Standard Unique Employer Identifier Final Rule on May 31, 2002 which adopted the Employer Identification Number (EIN) as the standard employer identifier to be used in HIPAA standard transactions.

The EIN, also known as a federal tax identification number, is issued by the Internal Revenue Service and is used to identify a business entity for tax reporting purposes.

The compliance date for using the EIN in standard transactions was July 30, 2004.

View the Regulation

National Provider Identifier (NPI)

HHS issued the HIPAA Administrative Simplification: Standard Unique Health Identifier for Health Care Providers Final Rule on January 23, 2004 which established the National Provider Identifier (NPI) standard as the unique provider identifier to be used in the HIPAA standard transactions.

As established by the regulation, the NPI is intelligence-free, meaning it does not carry any information about the health care provider, such as specialty. NPI’s are issued (enumerated) via the National Plan and Provider Enumeration System (NPPES).

The regulation also:

  • Established the criteria for determining which health care providers must obtain an NPI.
  • Defined the format of the NPI
  • Defined the enumeration requirements for individual health care providers and organizations.

The compliance date for using the NPI in standard transactions was May 23, 2007.

View the Regulation

Health Plan Identifier (HPID)

On October 28, 2019, the U.S. Department of Health and Human Services (HHS) issued a final rule that rescinds the adoption of the Health Plan Identifier (HPID) and Other Entity Identifier (OEID), as set forth in its original ruling Administrative Simplification: Adoption of a Standard for a Unique Health Plan Identifier (45 CFR Part 162).

This new regulation, entitled Administrative Simplification: Rescinding the Adoption of the Standard Unique Health Plan Identifier and Other Entity Identifier does the following:

  • Eliminates the requirements for health plans to obtain and use the HPID and eliminates the voluntary acquisition and use of the OEID.
  • Simplifies the process for deactivating HPIDs and OEIDs already issued.

The effective date of this rule was December 27, 2019. At this time any active HPID or OEID was automatically deactivated in the Health Plan or Other Entity Enumeration System (HPOES).

View the Regulation

Unique Patient Identifier (UPI)

While HIPAA requires HHS to establish a standard unique health identifier for patients, HHS has not issued any regulations adopting such a standard.