CLIA Lookup: Find or Verify a Lab's CLIA Number

1. Open QCOR's Search for a CLIA Laboratory page.
2. Fill in one of: Facility Name (or partial name), CLIA Identification Number, CLIA Lab Director, State, City or Zip Code. The fields are joined by "OR" on the form. A partial zip takes a star for each missing digit, such as 223**.
3. Pick a Certification Type if you want to narrow it: All, Compliance, Waiver, Accreditation or Microscopy - PPMP. There is no option for a registration certificate; the form notes that a lab applying for compliance or accreditation holds one until compliance is determined.
4. Tick the exempt-labs box for New York or Washington labs, or the international box for labs outside the United States.
5. Run the search. For each lab, QCOR gives the CLIA number, the facility name and the address where testing is done, the certificate type and the date the certificate expires.

Two lines on the page shape every result. "Search is only available for Active CLIA laboratories," and the list "is updated weekly and represents the information in the system at the time of update." For anything more about a particular lab, QCOR itself says to contact the State Agency or the CMS regional office.

An empty result is not proof that a lab is uncertified. Work through the usual reasons first:

• The name differs. QCOR lists the facility name the lab gave on its CMS-116, and that box reads "name of laboratory or hospital department". Search a short partial name, or ask for the number.
• The lab is new. A new waiver, PPM or registration certificate takes effect on the day the State Agency enters the CMS-116, and the listing refreshes weekly (SOM § 6006.6).
• It sits in an exempt state. Washington has a full exemption and New York a partial one; tick the exempt box.
• It is no longer active. QCOR shows active labs only, so a closed or terminated certificate drops out. CLIA certificate renewal covers what lapsing means.

If none of those fit, ask the lab for a copy of its certificate and confirm it with the State Agency for the lab's state (CMS State Agency contacts).

CMS calls it a "ten-character alpha-numeric CLIA identification number". The Claims Processing Manual (Ch. 16, § 70.4) fixes the pattern: positions 1 and 2 are the state code, position 3 is the letter D, and positions 4 to 10 are the number CMS's system assigns, which "no other laboratory in the country has".

Three practical readings follow from that:

• The state code can be out of date. It records where the lab was when it first applied. CMS's survey manual: "A laboratory that relocates to another State retains its original CLIA number" (SOM § 6008). A mismatch with the lab's address is not a red flag on its own.
• A third character that is not D means a typo. Claims with a number "inconsistent with the CLIA format" come back unprocessable (§ 70.10), so check it before it goes into a billing system.
• The number says nothing about the certificate. Type, effective date and expiry live in the CLIA data system, not in the ten characters. That is what the lookup is for.

In some CMS data systems the CLIA number appears in the column headed CMS Certification Number (CCN), so a spreadsheet from CMS may label it that way (SOM § 6008).

Medicare pays for a lab test only if the lab behind it holds a certificate that covers it. The Claims Processing Manual puts the number on the claim and checks it there:

• Where it goes. The number must be on each professional claim for lab services: field 23 of the paper CMS-1500, or the REF segment with qualifier X4 on the electronic 837 professional claim (§ 70.10). It is not required on the institutional claim (837I or CMS-1450).
• What gets a claim returned. No number, a number "inconsistent with the CLIA format", or more than one number unless the second is a reference lab's: each is returned as unprocessable.
• What gets a line denied. Medicare's Common Working File checks that "the laboratory identified by the CLIA number is certified to perform the test" (§ 70.3). A waiver or PPM number on a moderate complexity code fails that check; how waived codes pass is in QW modifier: when a CLIA-waived test needs it.
• One number per location. A physician who tests in two office labs sends a separate claim for each CLIA number.

Medicaid follows the same line: CMS's survey manual says a lab "cannot perform testing or claim Medicare and/or Medicaid payment for services performed without a CLIA certificate and/or valid CLIA identification number" (SOM § 6006). Commercial plans write their own claim rules, so check each payer's manual for the field it reads.

A lab may refer a specimen "only to a CLIA-certified laboratory or a laboratory meeting equivalent requirements as determined by CMS" (§ 493.1242(c)). The lookup is how you show you checked. A routine that holds up at inspection:

1. Get the reference lab's CLIA number in writing and find it in QCOR.
2. Check the certificate type covers what you send: a waiver or PPM certificate does not cover moderate or high complexity tests, PPM procedures aside.
3. Note the expiry date in your referral file, with the date you checked.
4. Keep a copy of the lab's current certificate, and recheck at each expiry or when its name or address changes.

QCOR shows the certificate, not the lab's record. For that, CMS publishes a Laboratory Registry once a year (§ 493.1850), compiled from the previous calendar year. It lists, among other things, labs convicted under fraud, false-billing or kickback laws; labs whose certificates were "suspended, limited, or revoked, and the reason"; labs under alternative sanctions (how survey findings are written up); and labs that lost their accreditation. The 2025 registry is the latest CMS links, with earlier years on its Laboratory Performance page.