HCPCS Level II modifier
Modifier QW
Modifier QW is a HCPCS Level II modifier. CMS describes it as: CLIA waived test.
Source: CMS HCPCS Level II, October 2026 file dated September 23, 2026. Publisher page
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- Modifier
- QW
- Type
- HCPCS Level II modifier, maintained by CMS
- CMS description
- CLIA waived test
- Claim form
- CMS-1500 item 24D, up to four modifiers per line. 837P SV101-3 to SV101-6.
- Guidance
- CMS HCPCS quarterly update
Laboratory
Related modifiers
- 90Reference (outside) laboratory
- 91Repeat clinical diagnostic lab test
- 92Alternative laboratory platform testing
- QXCRNA service: with medical direction by a physician
- QTRecording and storage on tape by an analog tape recorder
- QYMedical direction of one certified registered nurse anesthetist (CRNA) by an anesthesiologist
- QSMonitored anesthesia care service
- QZCRNA service: without medical direction by a physician
Related pages
- All CPT and HCPCS modifiersA to Z list
- CMS-1500 claim formModifiers go in item 24D
- Denial code CO-4Modifier missing or does not fit the code
- Denial code CO-182Modifier invalid on the date of service
- Denial code CO-B23Not allowed under the lab's CLIA certificate
- HCPCS Level II code lookup
- Denial and remark codes
Questions
What does modifier QW mean?
Modifier QW is a HCPCS Level II modifier. CMS describes it as: CLIA waived test.
Is modifier QW a CPT or a HCPCS modifier?
QW is a HCPCS Level II modifier from the CMS quarterly HCPCS file. Two-digit numeric modifiers, such as 25 or 59, are CPT modifiers.
Where does modifier QW go on a claim?
On the CMS-1500 it goes in item 24D next to the procedure code. Each line holds up to four modifiers. On an 837P it goes in SV101-3 to SV101-6.
What denial comes back when a modifier is wrong?
A missing or mismatched modifier often comes back as CARC 4. A modifier that was not valid on the date of service comes back as CARC 182. A bundling edit the modifier should have bypassed comes back as CARC 97 or 236.