How much does Medicare pay for CPT 85300?

Medicare allowed an average of $11.60 per service and paid $11.60 of that, the balance being the patient's coinsurance and deductible (2024 data). Providers submitted an average of $199.81, which is what they billed rather than what they received — Medicare pays its fee schedule regardless of the charge.

What is CPT code 85300?

Antithrombin iii antigen (clotting inhibitor) activity. It was billed 15,331 times to 14,735 Medicare beneficiaries by 91 providers in 2024.

Which specialty bills 85300 most?

Clinical Laboratory, with 15,282 services from 88 clinicians. Next are Pathology, Hematology-Oncology.

CPT 85300

Antithrombin iii antigen (clotting inhibitor) activity

$11.60Medicare-allowed amount per service, averaged across 15,331 services

Providers submitted

$199.81

Asking price, not received

Medicare allowed

$11.60

The fee schedule figure

Medicare paid

$11.60

Balance is patient coinsurance

Providers submitted an average of $199.81 for this code and Medicare allowed $11.60 — 17.2× less. That gap is normal and means nothing on its own: Medicare pays its fee schedule regardless of what is billed, so the submitted figure describes a hospital chargemaster, not a price anyone paid. Of the allowed amount Medicare paid $11.60 (100%); the rest is the patient’s coinsurance and deductible.

Services: 15,331
Beneficiaries: 14,735
Providers billing it: 91
Total allowed: $177,840

What Medicare pays for CPT 85300

Across 15,331 services billed by 91 providers to 14,735 beneficiaries, Medicare allowed an average of $11.60 per service. The allowed amount is the figure that matters: it is what Medicare and the patient together owe, set by the fee schedule and adjusted for local practice costs. What a provider chose to submit has no bearing on it.

Who bills 85300

Specialty	Services	Beneficiaries	Avg allowed	Providers
Clinical Laboratory	15,282	14,686	$11.60	88
Pathology	38	38	$11.61	2
Hematology-Oncology	11	11	$11.61	1

85300 reimbursement by state

Two different numbers. Allowed is what Medicare actually allowed in that state, which includes the local practice-cost adjustment. Standardized strips that geographic adjustment out of the payment, so it is the column to use when comparing states — a difference there reflects how the code was billed, not what it costs to run a practice locally.

State	Services	Allowed	Standardized pmt	Providers
New Jersey	2,922	$11.58	$11.61	4
North Carolina	2,262	$11.61	$11.61	3
Arizona	1,842	$11.59	$11.61	3
Texas	1,651	$11.60	$11.61	9
California	1,342	$11.60	$11.61	11
Florida	1,236	$11.61	$11.61	5
Georgia	512	$11.61	$11.61	1
New York	458	$11.61	$11.61	3
Tennessee	355	$11.61	$11.61	2
Kansas	319	$11.55	$11.61	4
Minnesota	315	$11.61	$11.61	2
Colorado	309	$11.61	$11.61	3
Massachusetts	257	$11.61	$11.61	4
Illinois	201	$11.61	$11.61	2
Ohio	184	$11.55	$11.61	3
Pennsylvania	176	$11.61	$11.61	5
Nevada	144	$11.61	$11.61	1
Oklahoma	111	$11.61	$11.61	3
Alabama	111	$11.48	$11.61	2
Wisconsin	111	$11.51	$11.61	2
Maryland	94	$11.61	$11.61	3
Washington	87	$11.59	$11.61	3
Virginia	62	$11.61	$11.61	2
New Mexico	62	$11.61	$11.61	1
Hawaii	50	$11.49	$11.61	2
Oregon	32	$11.61	$11.61	1
Iowa	31	$11.61	$11.61	2
Indiana	26	$11.61	$11.61	1
Utah	24	$11.61	$11.61	1
South Dakota	16	$10.60	$11.61	1
Louisiana	15	$11.61	$11.61	1
Connecticut	14	$10.94	$11.61	1

Related codes

85379Coagulation function measurement$9.96
85384Fibrinogen (factor 1) activity measurement$9.52
85390Coagulation function screening test$33.93
85306Protein s (clotting inhibitor) measurement$14.99
85385Fibrinogen (factor 1) antigen detection$14.16
85303Protein c antigen (clotting inhibitor) measurement$13.54
85305Protein s (clotting inhibitor) level$11.36
85302Protein c, (clotting inhibitor) activity$11.75
85307Activated protein resistance assay$14.99
85301Antithrombin iii antigen (clotting inhibitor) level$10.58
85347Coagulation time measurement$4.18
85362Coagulation function analysis$6.73

Billing this code is not the same as earning it

An allowed amount is revenue to a practice, not income to a clinician. It funds staff, premises, equipment and supplies before anyone is paid. What clinicians actually earn is published separately by the Department of Labor, and what industry pays them is published separately again by CMS — this site carries both.

What doctors are paid →·Look up a clinician →·All procedure codes →

Where this comes from. CMS Medicare Physician & Other Practitioners, by Provider and Service, 2024. It covers fee-for-service Original Medicare Part B only — not Medicare Advantage, not Medicaid, and not commercial insurance, which typically pays more for the same code.

How it is averaged. CMS publishes one average per provider per code. Every figure here is re-weighted by the number of services, so a clinician who billed the code 4,000 times counts 4,000 times more than one who billed it twice. CMS also suppresses any provider-code pair with fewer than 11 beneficiaries, so low-volume practice is missing from these totals by design.