Particle or latex agglutination screen for a specific antibody, reported once per antibody when no dedicated code exists for that antibody.
- Medicare
- $0.00
- Work RVU
- 0
- Global, days
- Region
- General
Documentation requirements
What must appear in the operative or office note to support the claim.
Source · Editorial brief grounded in 2 cited references ↓
- Antibody being screened, named on the order
- Clinical reason for the screen
- Lab report showing agglutination method
- Unit count matching distinct antibodies
- Confirmation no specific antibody code applies
Applicable modifiers
Modifiers commonly billed with this code.
Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual
What this code covers
Source · Editorial summary grounded in 2 cited references ↓
86403 is a method code for particle agglutination antibody screens, one unit per antibody. Latex agglutination tests clump visibly when the antibody is present. The code is used only when the antibody being screened has no specific CPT code of its own. If it does, bill the specific code even if the lab used agglutination.
Orthopedic practices rarely bill it directly. It comes up in infectious and inflammatory workups that a lab or specialist builds, and on reference lab claims for patients the practice is following. Rheumatoid factor, which many labs run by agglutination, has its own codes (86430 and 86431), so it should not land on 86403.
If the lab follows a positive screen with a titer, the titer has its own code (86406). Payers deny 86403 when the antibody tested is not named, or when units exceed the number of distinct antibodies on the report.
RVU & reimbursement
Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.
Source · CMS Physician Fee Schedule, RVU26A · January 2026
| Work RVU | 0 |
| Practice expense RVU | 0 |
| Malpractice RVU | 0 |
| Total RVU | 0 |
| Medicare national rate | $0.00 |
| Global period | days |
Payment by site of service
Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.
Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026
| Setting | Medicare rate (national) |
|---|---|
Office (PFS non-facility) Procedure performed in physician's office | $0.00 |
Common denial reasons
The recurring reasons claims for CPT 86403 get rejected.
Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓
- Rheumatoid factor billed as 86403
- Antibody has its own CPT code
- Units exceed antibodies documented
- Titer billed without positive screen
- Diagnosis does not support the test
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 2 cited references ↓
01Is rheumatoid factor billed with 86403?
02What is the titer code for 86403?
03How many units of 86403 can I bill?
Sources & references
Editorial content was developed using the following public sources.
- 01CMS Physician Fee Schedule 2026
- 02cms.govhttps://www.cms.gov/medicare/payment/fee-schedules/clinical-laboratory-fee-schedule-clfs
Mira Scribe
Mira Scribe records the clinical question behind each lab ordered, so method-based codes like this one have a named reason on file.
See how Mira captures CPT 86403 documentation