A National Provider Identifier (NPI) is a unique 10-digit number used to identify health care providers. Providers and organizations use their NPI when submitting claims, receiving payments, verifying eligibility, enrolling in Medicare, and conducting other administrative transactions. Once assigned, an NPI remains with the provider and does not change due to changes in practice location, specialty, or employer.

If you plan to bill Medicare, enroll in Medicare, order or certify services, prescribe medications, or participate in other HIPAA-covered transactions, obtaining and maintaining the appropriate NPI is an important first step. Claims submitted without a valid NPI may be unprocessable, resulting in billing delays and administrative burden.

Before You Enroll in Medicare

Obtaining an NPI is one of the first steps in Medicare enrollment. NPIs are issued through the National Plan and Provider Enumeration System (NPPES), the CMS system used to assign and maintain provider identifiers. Information entered into NPPES is used throughout the enrollment process and should be reviewed carefully before submitting a Medicare enrollment application.

Before beginning enrollment, verify that your legal name, addresses, contact information, and taxonomy information are accurate and current. Information that does not match across systems can result in enrollment delays, development requests, billing issues, or claim rejections.

Determine Which NPI You Need

There are two types of NPIs.

A Type 1 NPI is assigned to individual health care providers who furnish services, such as physicians, non-physician practitioners, therapists, and other individual providers. Each individual may only have one Type 1 NPI, which remains with them throughout their career.

A Type 2 NPI is assigned to organizations such as hospitals, physician groups, clinics, skilled nursing facilities, home health agencies, laboratories, suppliers, and pharmacies. Organizations may need one or more Type 2 NPIs depending on their operational structure and business needs.

Selecting the correct NPI type is essential to successful enrollment and accurate claim submission. Providers who operate both as individuals and as organizations may require both a Type 1 and Type 2 NPI.

Apply for or Manage an NPI

CMS recommends using the online NPPES application process because it is the fastest and most efficient way to obtain or update an NPI. NPPES allows providers to apply for an NPI, update provider information, maintain taxonomy information, and review NPI records.

Keep Your Information Up to Date

Maintaining accurate NPI information is an ongoing responsibility. Providers should review their NPPES records regularly and update information whenever changes occur. This includes changes to:

• Legal name
• Practice or mailing address
• Taxonomy (specialty) information
• Contact information
• Ownership information
• Authorized official information

Accurate provider data helps support enrollment processing, claims submission, provider directory information, and communication with Medicare contractors and health plans.

Avoid Common NPI Issues

Many enrollment and billing problems can be avoided through routine review of NPI information. Before submitting an enrollment application or billing Medicare, confirm that:

• Your NPI is active
• Your legal name matches IRS records
• Addresses and contact information are current
• Taxonomy information accurately reflects your specialty or provider type
• Individual and organizational NPIs are reported correctly
• Information in NPPES matches your Medicare enrollment record
  • Updates do not automatically transfer between systems

Taking these steps can help prevent application delays, claim processing issues, unnecessary development requests, and payment interruptions.

Verify Your Public NPI Information

Information maintained in NPPES is publicly available through the NPI Registry. Providers should periodically review their public record to ensure the information available to health plans, Medicare Administrative Contractors (MACs), credentialing organizations, and other stakeholders remains accurate.

Special Considerations for Your Provider Type

Institutional providers often maintain complex organizational structures involving multiple practice locations, provider-based entities, departments, and Medicare identifiers. Hospitals, skilled nursing facilities, rural health clinics, federally qualified health centers, ESRD facilities, and other institutional providers should ensure that organizational NPIs, Medicare enrollment records, and legal business information remain aligned across all systems. Failure to maintain accurate information can create enrollment and billing complications, particularly when ownership, locations, or organizational structures change.