CPT code 80173: Haloperidol level, therapeutic drug assay2026 Medicare lab fee · Clinical Laboratory Fee Schedule
A haloperidol assay measures medication concentration in a patient specimen for therapeutic drug monitoring when a clinician orders a measured level.
Medicare pays $15.78 for 80173 under the 2026 Clinical Laboratory Fee Schedule: one national amount, the same in every state and setting.
Medicare lab fee · CLFS 2026 Q4
National CLFS amount
$15.78
In effect since Jan 1, 2026. The same amount in every state, payment locality and setting.
- Geographic adjustment
- None
- Office vs facility
- Same
- Since 2020
- Unchanged
- CMS updates
- Quarterly
Medicare pays the lesser of the lab’s charge and this amount. Patients usually owe no Part B deductible or coinsurance for covered clinical lab tests.
On this page 7 sections
What 80173 covers
80173 identifies a laboratory assay that measures haloperidol concentration in a patient specimen. Clinicians use it for therapeutic drug monitoring when they need a measured level of this medication. The result is specific to haloperidol and is distinct from assays for other medications, such as clozapine or lithium. A laboratory performs and reports the assay, and the ordering clinician considers the result in medication management.
Medicare pays 80173 under the CLFS, not the physician fee schedule. The CLFS sets one national amount per code that applies across states and localities, with no geographic or office-versus-facility adjustment. The 2026 national amount is $15.78, unchanged from 2020 through 2026. Report 80173 for the haloperidol assay performed.
This summary was written with AI assistance from CMS Clinical Laboratory Fee Schedule data. Amounts on this page come directly from CMS files.
How Medicare pays 80173
Clinical lab tests aren’t priced like physician services. They’re paid from their own fee schedule, with its own rules. See the whole lab fee schedule.
One national amount
CMS sets a single Clinical Laboratory Fee Schedule amount for 80173. There’s no geographic (GPCI) adjustment, so it pays the same in every state and payment locality.
No office or facility rate
Lab tests aren’t built from relative value units, so there’s no office and facility split: the place of service doesn’t change the CLFS amount.
Updated every quarter
CMS republishes the CLFS each quarter. New tests, often proprietary laboratory analyses (PLA codes), join during the year; existing amounts are updated each January.
Excluded from the physician fee schedule
The physician fee schedule lists 80173 with status X (excluded by statute), so the test itself is paid only from the CLFS.
80173 on the lab fee schedule since 2020
80173 · CLFS 2026 Q4 (current)
$15.78
Unchanged since Jan 1, 2020
27 quarterly CLFS releases on file, first CLFS 2020 Q1. A code missing from a quarter wasn’t on that release.
80173 compared with similar tests
- 80159Clozapine level$20.15
- 80159 measures clozapine, not haloperidol. Select the assay for the medication whose concentration is being measured.
- 80178Lithium levelQuantitative drug monitoring$6.61
- 80178 measures lithium. It is not interchangeable with a haloperidol assay.
- 80185Phenytoin levelTotal drug concentration$13.25
- 80185 measures total phenytoin concentration. Use 80173 for haloperidol rather than selecting by the general purpose of drug-level monitoring.
80173 billing questions
What does 80173 measure?
It measures haloperidol concentration in a patient specimen. It is specific to haloperidol, not a general drug screen.
When is this assay used?
It is used for therapeutic drug monitoring when a clinician orders a measured haloperidol level.
How is 80173 different from 80159 or 80178?
80173 measures haloperidol; 80159 measures clozapine, and 80178 measures lithium. Select the assay for the medication being measured.
How does Medicare pay for 80173?
Medicare pays it under the CLFS at one national amount across localities, without an office-versus-facility adjustment. It is excluded from the physician fee schedule.
Where this amount comes from
FeeBase reads lab amounts directly from the CMS Clinical Laboratory Fee Schedule file for the quarter: one row per code, with its payment indicator and national amount. Contractor-priced tests are labeled, never given a made-up amount. Amounts are Medicare payment limits, not a patient’s bill or a commercial rate.
CMS CLFS 2026 Q4 · effective Oct 1, 2026 through the day before Jan 1, 2027
Show the CMS file line behind this amount
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