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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

DR. WILLIAM CHERNIAK MD, MPH
NPI 1649635095
Emergency Medicine in Newport Beach, CA

Active since December 29, 2015PECOS Enrolled
881 DOVER DR STE 200, NEWPORT BEACH, CA 92663(213) 838-5818(203) 822-6295 Get Directions Write a Review

NPPES record last updated: October 30, 2026. Verified against the NPPES registry weekly; last sync: November 08, 2026.

Record update history: Oct 30, 2026, Aug 11, 2026, Jul 9, 2024 and 2 more (5 updates tracked since 2015).

About Dr. William Cherniak Md, Mph NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. WILLIAM CHERNIAK MD, MPH (NPI 1649635095) is an individual emergency medicine provider in Newport Beach, California, licensed in California (A157750) and active in the NPI registry since December 2015. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1649635095
Entity TypeIndividualMale
Primary Taxonomy207P00000X
Provider Legal NameDR. WILLIAM CHERNIAKCredential: MD, MPH
Location Address881 DOVER DR STE 200Newport Beach, CA 92663-6922
Mailing Address2219 Main St Unit 653Santa Monica, CA 90405-2217 · (213) 838-5818 · Fax (203) 822-6295
Phone(213) 838-5818
Fax(203) 822-6295
Sole ProprietorYes
Enumeration DateDecember 29, 2015
Last NPPES UpdateOctober 30, 20265 updates tracked since enumeration
NPPES CertifiedOctober 30, 2026
✔ NPI 1649635095 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyEmergency MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207P00000X
License✔ Licensed in CA · A157750
Definition
An emergency physician focuses on the immediate decision making and action necessary to prevent death or any further disability both in the pre-hospital setting by directing emergency medical technicians and in the emergency department. The emergency physician provides immediate recognition, evaluation, care, stabilization and disposition of a generally diversified population of adult and pediatric patients in response to acute illness and injury.
Also ListedClinic/Center · Urgent CareTaxonomy 261QU0200X · License D80655 (MD)
881 DOVER DR STE 200, Newport Beach, CA 92663
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. William Cherniak Md, Mph is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show William Cherniak reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Rocket Doctor Practice Group, P.C.
Same address
Emergency Medicine
881 DOVER DR STE 200
Newport Beach, CA 92663
  • Reassigned Medicare billing, California, Maryland and New York enrollments
  • Medicare enrollment name: Rocket Doctor Practice Group PC
  • 40 clinicians in this Medicare group
NPI 1194403642 (213) 838-5818

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 92663 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$96.36 typical visit price
range $62.96 – $187.60
Typical copayment $24.09 (range $15.74 – $46.90)
Most-billed visit code 99203
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

ROCKET DOCTOR PRACTICE GROUP, P.C.
Emergency Medicine
881 DOVER DR STE 200
NEWPORT BEACH, CA 92663
Orange County (213) 838-5818

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is William Cherniak's NPI number?

The NPI number for William Cherniak is 1649635095. It was assigned to this individual provider in the NPPES registry on December 29, 2015.

Where is William Cherniak located?

William Cherniak practices at 881 Dover Dr Ste 200, Newport Beach, CA 92663. The listed phone number is (213) 838-5818.

What is William Cherniak's specialty?

The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.

Is William Cherniak enrolled in Medicare?

Yes. William Cherniak is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for William Cherniak's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Cherniak reassigns Medicare benefits to Rocket Doctor Practice Group, P.C. (Newport Beach, CA). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for William Cherniak's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for William Cherniak was last updated on October 30, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 12 days ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.