QWHCPCS Level II

Clia waived test

Usage notes
Append to a laboratory test code to identify it as a CLIA-waived test performed under the facility's CLIA certificate of waiver.
Common mistakes
Appending QW to a test that isn't actually on CMS's CLIA-waived test list, which triggers a denial since not every lab code qualifies for QW.

Related modifiers

Frequently asked questions

What does modifier QW mean?

Clia waived test

When do I use modifier QW?

Append to a laboratory test code to identify it as a CLIA-waived test performed under the facility's CLIA certificate of waiver.

What's a common mistake with modifier QW?

Appending QW to a test that isn't actually on CMS's CLIA-waived test list, which triggers a denial since not every lab code qualifies for QW.

HCPCS modifier data from CMS. CPT® is a registered trademark of the American Medical Association — CPT modifier descriptions are not included on this site. Always verify codes with authoritative sources before making billing decisions.