How much does Medicare pay for CPT 83518?

Medicare allowed an average of $9.43 per service and paid $9.43 of that, the balance being the patient's coinsurance and deductible (2024 data). Providers submitted an average of $30.08, which is what they billed rather than what they received — Medicare pays its fee schedule regardless of the charge.

What is CPT code 83518?

Analysis of substance using immunoassay technique, single step method. It was billed 3,355 times to 2,888 Medicare beneficiaries by 31 providers in 2024.

Which specialty bills 83518 most?

Family Practice, with 1,664 services from 12 clinicians. Next are Internal Medicine, Clinical Laboratory, Urology.

CPT 83518

Analysis of substance using immunoassay technique, single step method

$9.43Medicare-allowed amount per service, averaged across 3,355 services

Providers submitted

$30.08

Asking price, not received

Medicare allowed

$9.43

The fee schedule figure

Medicare paid

$9.43

Balance is patient coinsurance

Providers submitted an average of $30.08 for this code and Medicare allowed $9.43 — 3.2× 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 $9.43 (100%); the rest is the patient’s coinsurance and deductible.

Services: 3,355
Beneficiaries: 2,888
Providers billing it: 31
Total allowed: $31,638

What Medicare pays for CPT 83518

Across 3,355 services billed by 31 providers to 2,888 beneficiaries, Medicare allowed an average of $9.43 per service. That is 1.2 services per beneficiary, so this is a code patients typically receive more than once. 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 83518

Specialty	Services	Beneficiaries	Avg allowed	Providers
Family Practice	1,664	1,382	$9.44	12
Internal Medicine	1,216	1,107	$9.43	12
Clinical Laboratory	272	258	$9.43	5
Urology	178	118	$9.45	1
Nurse Practitioner	25	23	$9.29	1

83518 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
Florida	1,343	$9.44	$9.45	11
Oklahoma	476	$9.43	$9.45	2
New Jersey	364	$9.45	$9.45	3
California	363	$9.45	$9.45	4
Alabama	282	$9.42	$9.45	1
Minnesota	158	$9.44	$9.45	1
Mississippi	130	$9.45	$9.45	1
Tennessee	64	$9.30	$9.45	2
Ohio	62	$9.30	$9.45	2
Arizona	60	$9.41	$9.45	1
New York	27	$9.45	$9.45	2
North Dakota	26	$9.45	$9.45	1

Related codes

83540Iron level$6.33
83550Iron binding capacity$8.55
83521Measurement of immunoglobulin light chains$16.90
83520Measurement of substance$16.87
83516Analysis of substance$11.28
83525Insulin measurement$11.18
83519Measurement of substance$18.00
83529Measurement of interleukin-6$16.91
83527Insulin measurement$12.66

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.