What does code 84394 cost?

Across the published hospital price files, the disclosed cash price for 84394 ranges from $226 to $432. This is public hospital price transparency data, not a guaranteed estimate of your bill.

Will this be my final bill?

Actual patient responsibility may vary based on your insurance plan, deductible, coinsurance, network status, diagnosis, setting, bundled services, clinical circumstances, and hospital billing practices.

84394 is the billing code hospitals use to identify "HC TOTAL TAU (TTAU)" on their published price files. We use it to line up the same service across different hospitals.

Why do prices for this code differ between hospitals?

Each hospital sets its own prices and negotiates separately with each insurer, so the disclosed price for the same code can vary widely from one hospital to another — and even between plans at a single hospital. Comparing the published figures is what this page is for; a difference does not by itself mean one hospital is better or worse.

What this page is not

It is not a quote, a guarantee, or medical advice. It shows what hospitals have published for this code, so you can compare and ask informed questions — your actual cost depends on your insurance, the exact services performed, and the care setting.

84394

HCPCS

HC TOTAL TAU (TTAU)

Verified from hospital fileNot a bill estimate

iDirect answer

Based on the latest published hospital price files, code 84394 (HC TOTAL TAU (TTAU)) appears at 18 hospitals with disclosed cash prices from $226 to $432. This is public hospital price transparency data, not a guaranteed estimate of your bill.

Published-price availability

hospitals publish a price

list this service without a published price

Cash

List

Negotiated

Allowed

A blank price (“—”) means a hospital names this service but did not publish a dollar amount — it is not a free service or a $0 price.

Compare 84394 prices

Filter by hospital, city, setting, or payer — the summary and charts update with your filters.

Based on hospital-published prices verified from each hospital’s own file. Coverage expands as data is verified.

Published cash prices for code 84394 vary by about 91% across the 16 hospitals with disclosed prices here — from $226 to $432. Shopping around can matter.

Hospitals

Prices shown

$226

Lowest cash

$432

Highest cash

code 84394 cash price16 disclosed · 16 hospitals

$226median ~$313$432

Lowest cash price by hospital

Cash price by city

Reflects your current filters.

Cash price by city$226 – $313

Morganfield · 1 hospital$226
Princeton · 1 hospital$254
Mequon · 1 hospital$300
New Berlin · 1 hospital$300
Oak Creek · 1 hospital$300
Hazel Crest · 1 hospital$313

20 prices shown.

Service	Hospital	Code	List price	Cash price	Negotiated range	Allowed (median)
HC TOTAL TAU (TTAU) Inpatient & outpatient	Endeavor Health Edward Hospital	84394 HCPCS	$432	$432	—	—
Total tau Outpatient	Endeavor Health Edward Hospital	84394 HCPCS	—	—	$129 – $208	—
Hc Alzheimer's Disease Evaluation, Total Tau, Csf Inpatient & outpatient	University of Chicago Medical Center	84394 HCPCS	—	—	—	—
Total tau Outpatient	University of Chicago Medical Center	84394 HCPCS	—	—	—	—
TAU PROTEIN TOTAL Outpatient	Advocate South Suburban Hospital	84394 CPT	$625	$313	$218 – $609	—
84394 Test for total Tau protein Inpatient	Memorial Hospital of South Bend	84394 CPT	$648	$421	$130 – $531	—
TAU PROTEIN TOTAL Inpatient	Aurora BayCare Medical Center	84394 CPT	$625	$313	$375 – $531	—
TAU PROTEIN TOTAL Inpatient	Aurora Medical Center Burlington	84394 CPT	$625	$313	$375 – $531	—
TAU PROTEIN TOTAL Inpatient	Aurora Medical Center Bay Area	84394 CPT	$625	$313	$375 – $529	—
TAU PROTEIN TOTAL Inpatient	Aurora Medical Center Fond du Lac	84394 CPT	$625	$313	$375 – $531	—
TAU PROTEIN TOTAL Inpatient	Aurora Medical Center Grafton	84394 CPT	$625	$313	$375 – $531	—
TAU PROTEIN TOTAL Inpatient	Aurora Medical Center Kenosha	84394 CPT	$625	$313	$375 – $531	—
TAU PROTEIN TOTAL Inpatient	Aurora Lakeland Medical Center	84394 CPT	$625	$313	$375 – $531	—
HC ALZHEIMER TAU, TOTAL Inpatient	Froedtert Holy Family Memorial Hospital	84394 CPT	$642	$353	$385 – $565	—
HC ALZHEIMER TAU, TOTAL Inpatient	Froedtert Community Hospital - Mequon	84394 CPT	$546	$300	$327 – $480	—
HC ALZHEIMER TAU, TOTAL Outpatient	Froedtert Community Hospital - New Berlin	84394 CPT	$546	$300	$218 – $480	—
HC ALZHEIMER TAU, TOTAL Inpatient	Froedtert Community Hospital - Oak Creek	84394 CPT	$546	$300	$327 – $480	—
HC TOTAL TAU CSF Inpatient	Deaconess Gibson Hospital	84394 CPT	$480	$254	$254 – $432	—
HC TOTAL TAU CSF Inpatient	Deaconess Union County Hospital	84394 CPT	$480	$226	$226 – $466	—
TOTAL TAU Outpatient	Texas Health Center for Diagnostics and Surgery Plano	84394 CPT	—	—	$253 – $273	—

How to read these prices

Cash price: The discounted self-pay price for paying directly, without insurance.
List price: The hospital’s full undiscounted charge — rarely what anyone pays.
Negotiated rate: A rate for a specific insurer and plan; your share depends on your benefits.
Allowed amount: A historical reference for what was actually allowed, where disclosed.

Hospitals that publish 84394 prices

Open a hospital to see this code in the context of its full published prices.

Endeavor Health Edward Hospital University of Chicago Medical Center Advocate South Suburban Hospital Memorial Hospital of South Bend Aurora BayCare Medical Center Aurora Medical Center Burlington Aurora Medical Center Bay Area Aurora Medical Center Fond du Lac Aurora Medical Center Grafton Aurora Medical Center Kenosha Aurora Lakeland Medical Center Froedtert Holy Family Memorial Hospital Froedtert Community Hospital - Mequon Froedtert Community Hospital - New Berlin Froedtert Community Hospital - Oak Creek Deaconess Gibson Hospital Deaconess Union County Hospital Texas Health Center for Diagnostics and Surgery Plano

Code 84394: frequently asked

What does code 84394 cost?: Across the published hospital price files, the disclosed cash price for 84394 ranges from $226 to $432. This is public hospital price transparency data, not a guaranteed estimate of your bill.
Will this be my final bill?: Actual patient responsibility may vary based on your insurance plan, deductible, coinsurance, network status, diagnosis, setting, bundled services, clinical circumstances, and hospital billing practices.
What is code 84394?: 84394 is the billing code hospitals use to identify "HC TOTAL TAU (TTAU)" on their published price files. We use it to line up the same service across different hospitals.
Why do prices for this code differ between hospitals?: Each hospital sets its own prices and negotiates separately with each insurer, so the disclosed price for the same code can vary widely from one hospital to another — and even between plans at a single hospital. Comparing the published figures is what this page is for; a difference does not by itself mean one hospital is better or worse.
What this page is not: It is not a quote, a guarantee, or medical advice. It shows what hospitals have published for this code, so you can compare and ask informed questions — your actual cost depends on your insurance, the exact services performed, and the care setting.

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