Clinical Laboratory Improvement Amendments (CLIA)

Clinical Laboratory Improvement Amendments of 1988 (CLIA) amended the Public Health Service Act to extend jurisdiction of the Department of Health and Human Services (HHS) to regulate all laboratories that test human specimens for the purpose of providing information for diagnosis, prevention, or treatment of any disease or impairment of, or the assessment of the health of, human beings. All information can be found in CMS Internet Only Manual (IOM), Publication 100-08, Medicare Program Integrity Manual, Chapter 15, Section


CLIA mandates that all laboratories, including physician office laboratories; meet applicable Federal requirements and have a CLIA certificate to operate.

The following are requirements for all laboratories or entities that perform laboratory testing.

  • Pay user fees as assessed by CMS to finance the entire cost of administering the CLIA program
  • Submit specific information to HHS or its designee
  • Comply with specific administrative and program requirements
  • Submit to surveys to assess compliance with CLIA requirements
  • Be subject to specified enforcement actions
  • Apply for CLIA certificates based on the complexity of testing performed in the laboratory or based on accreditation by a CMS-approved accreditation organization
  • Be located in a State with a CMS approved State laboratory licensure program, be licensed or approved in accordance with state requirements.


All laboratories, apart from laboratories licensed by a state with a CMS-approved state laboratory licensure program (CLIA-exempt laboratories); must obtain a CLIA certificate to operate. Although CLIA-exempt laboratories do not need a CLIA certificate to operate, they are assigned a CLIA identification number for Medicare payment purposes.

Certain types of laboratories and laboratory tests are not subject to meeting CLIA requirements. These include:

  • Any facility or component of a facility that performs testing strictly for forensic purposes
  • Research laboratories that do not report patient specific results (although they test human specimens) for the diagnosis, prevention or treatment of any disease or impairment of, or the assessment of the health of individuals
  • Components or functions of laboratories certified by the Substance Abuse and Mental Health Services Administration (SAMHSA), in which drug testing is performed that meets SAMHSA guidelines and regulations. (However, all other testing conducted by a SAMHSA certified laboratory is subject to this rule.)
  • Laboratories under the jurisdiction of the Department of Veterans Affair)
  • Department of Defense (DoD) laboratories are subject to requirements that CMS has determined to be comparable to those in CLIA. The DoD is responsible for assuring compliance with these requirements and for oversight of its laboratories under a Memorandum of Understanding (MOU) between the Secretary of HHS and the Secretary of DoD. (See §6022 for discussions on Federal laboratories.)
  • Laboratory testing conducted in conjunction with the provision of home health or hospice care in an individual's home, where the home health agency or hospice employee merely assists the individual in performing a test, since tests performed by individuals in the home are not subject to CLIA
  • Laboratories licensed in a state whose laboratory licensure program is approved by CMS
  • Facilities which serve only as collection stations. A collection station receives specimens to be forwarded to a laboratory performing diagnostic tests
  • Radiological facilities that perform only imaging procedures (e.g., x-rays, ultrasounds, Magnetic Resonance Imaging, Computerized Tomography)
  • Facilities performing only physiological testing, e.g. spirometry, slit-lamp test for eyes, breath analysis, pulse oximetry
  • Any facility or component of a facility that performs testing for drugs of abuse for employment purposes.

Application Completion

  • Each practice location at which laboratory tests are performed must submit to the contractor a separate CLIA certificate for that location. The only exceptions to this rule are:
    • Laboratories within a hospital that are located at contiguous buildings, on the same campus and under common direction
    • Non-profit or governmental laboratories that engage in limited public health testing
    • Laboratories that are not at a fixed location (i.e., are mobile)
  • The laboratory must submit to the contractor a separate certificate for each state in which testing is performed.
  • If a lab is under the same ownership and at the same location, it generally does not need to enroll separately. The enrolling provider will simply furnish its CLIA number in the practice location section.
    • If a lab is an Independent CLIA lab, it must enroll separately.
  • A separate enrollment record need not be created for each CLIA number.
    • For example: Suppose a physician is enrolling in Medicare and has a CLIA number. The Noridian will only create a single enrollment record that will encompass the CLIA number.
  • If completing application via PECOS, ensure application questionnaire is answered correctly. CMS-855B, CMS-588 (Electronic Funds Transfer (EFT)) application will populate.
  • If completing application via paper, the following must be submitted:
  • A voided check or signed bank letter is necessary documentation for EFT portion of application
  • Must include legal business name (LBN) of the enrollment, routing and account number and practice address
  • Submit application fee
    • Fee is required for application. Can be paid on PECOS website
    • Select pay application fee on right-hand side under Helpful Links

Effective Dates

Medicare can go back 30 days from when the application is submitted, or all signatures are received in PECOS.

An application can be submitted 60 days in advance of when the enrollment will be active.

Supporting Documents

  • IRS document when:
    • Initial enrollment
    • A change of legal business name
  • A voided check or signed bank letter is necessary documentation for EFT portion of application
  • Any certification the CLIA issued from CMS



Last Updated Oct 28 , 2022