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DR. WILLIAM GREGORY MITCHELL MD
NPI 1538629621
Internal Medicine - Gastroenterology in Bronx, NY

Active since March 23, 2019PECOS Enrolled
111 E 210TH ST, BRONX, NY 10467(718) 920-4321 Get Directions Write a Review

NPPES record last updated: December 21, 2025. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Dec 21, 2025, Mar 23, 2019 (2 updates tracked since 2019).

About Dr. William Gregory Mitchell Md NPPES

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

DR. WILLIAM GREGORY MITCHELL MD (NPI 1538629621) is an individual gastroenterology provider in Bronx, New York, licensed in New York (314628) and active in the NPI registry since March 2019. He is enrolled in Medicare PECOS, is affiliated with Montefiore Medical Center, and is a graduate of Albert Einstein College Of Medicine Of Yeshiva University (2019).

NPPES Registry Identity

NPI1538629621
Entity TypeIndividualMale
Primary Taxonomy207RG0100X
Provider Legal NameDR. WILLIAM GREGORY MITCHELLCredential: MD
Location Address111 E 210TH STBronx, NY 10467-2401
Mailing Address111 E 210th StBronx, NY 10467-2401 · (718) 920-4321
Phone(718) 920-4321
Sole ProprietorYes
Medical School CMSAlbert Einstein College Of Medicine Of Yeshiva UniversityGraduated 2019
Enumeration DateMarch 23, 2019
Last NPPES UpdateDecember 21, 20252 updates tracked since enumeration
NPPES CertifiedDecember 21, 2025
✔ NPI 1538629621 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License✔ Licensed in NY · 314628
Definition
An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.
111 E 210TH ST, Bronx, NY 10467
Open in Google Maps ↗

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 Gregory Mitchell Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID9234460593
PECOS Enrollment IDI20250828003598
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 Mitchell reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Montefiore Medical Center
Same address
Anesthesiology
111 E 210TH ST
Bronx, NY 10467
  • Reassigned Medicare billing, New York enrollment
  • 5,251 clinicians in this Medicare group
NPI 1063525152 (914) 378-6021

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

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Montefiore Medical Center

Acute Care Hospitals · Bronx, NY
2/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number330059
Location111 East 210th StreetBronx, NY 10467 · Bronx County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 10467 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
$154.28 typical visit price
range $67.40 – $203.53
Typical copayment $38.57 (range $16.85 – $50.88)
Most-billed visit code 99204
Established Patient
$117.62 typical visit price
range $21.66 – $164.45
Typical copayment $29.40 (range $5.41 – $41.11)
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 20

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

HEATHER ROOT MD
Internal Medicine (Infectious Disease)
111 E 210TH ST
BRONX, NY 10467
Bronx County (718) 920-8592
MICHAEL GOTTESMAN M.D.
Radiology (Diagnostic Neuroimaging)
111 E 210TH ST
BRONX, NY 10467
Bronx County (718) 920-5506
JIAE LEE M.D.
Psychiatry & Neurology (Neurology)
111 E 210TH ST
BRONX, NY 10467
Bronx County (718) 920-4321
DR. MICHELLE DOMINIQUE PINTEA MD
Pediatrics
111 E 210TH ST
BRONX, NY 10467
Bronx County (718) 920-4321
TELISHA MCLEAN
Nurse Practitioner (Family)
111 E 210TH ST
BRONX, NY 10467
Bronx County (718) 920-4321
SHIVADITYA CHOUDHURY
Anesthesiology
111 E 210TH ST
BRONX, NY 10467
Bronx County (718) 920-4321
MS. JOHANNA SHEA-FEN TAN
Student in an Organized Health Care Education/Training Program
111 E 210TH ST
BRONX, NY 10467
Bronx County (718) 920-4321
JACK DANIEL HALLIGAN MD
Pediatrics
111 E 210TH ST
BRONX, NY 10467
Bronx County (718) 920-4321

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 Mitchell's NPI number?

The NPI number for William Mitchell is 1538629621. It was assigned to this individual provider in the NPPES registry on March 23, 2019.

Where is William Mitchell located?

William Mitchell practices at 111 E 210th St, Bronx, NY 10467. The listed phone number is (718) 920-4321.

What is William Mitchell's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is William Mitchell enrolled in Medicare?

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

Which organization bills Medicare for William Mitchell's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Mitchell reassigns Medicare benefits to Montefiore Medical Center (Bronx, NY). 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 Mitchell's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is William Mitchell affiliated with any hospitals?

According to CMS data, William Mitchell is affiliated with Montefiore Medical Center.

When was this NPI record last updated?

The NPPES record for William Mitchell was last updated on December 21, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 months 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.