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WONSEOK WILLIAM CHOI
NPI 1801415781
Internal Medicine - Hematology & Oncology in Boston, MA

Active since April 10, 2020PECOS Enrolled
800 WASHINGTON ST, BOSTON, MA 02111(617) 636-5000 Get Directions Write a Review

NPPES record last updated: June 22, 2023. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Jun 22, 2023, Apr 10, 2020 (2 updates tracked since 2020).

About Wonseok William Choi NPPES

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

WONSEOK WILLIAM CHOI (NPI 1801415781) is an individual hematology & oncology provider in Boston, Massachusetts, licensed in Massachusetts (3013509) and active in the NPI registry since April 2020. He is enrolled in Medicare PECOS, is affiliated with Tufts Medical Center, and maintains a secondary practice location in Washington.

NPPES Registry Identity

NPI1801415781
Entity TypeIndividualMale
Primary Taxonomy207RH0003X
Provider Legal NameWONSEOK WILLIAM CHOI
Location Address800 WASHINGTON STBoston, MA 02111-1552
Mailing Address800 Washington StBoston, MA 02111-1552 · (617) 636-5000
Phone(617) 636-5000
Sole ProprietorYes
Medical School CMSGeorge Washington University School Of MedicineGraduated 2020
Enumeration DateApril 10, 2020
Last NPPES UpdateJune 22, 20232 updates tracked since enumeration
NPPES CertifiedJune 22, 2023
✔ NPI 1801415781 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · Hematology & OncologyAllopathic & Osteopathic Physicians
Taxonomy Code207RH0003X
License✔ Licensed in MA · 3013509
Definition
An internist doctor of osteopathy that specializes in the treatment of the combination of hematology and oncology disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine WAS able to obtain a Certificate of Special Qualifications in the field of Hematology and Oncology. The Certificate is NO longer offered.
Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X
800 WASHINGTON ST, Boston, MA 02111
Open in Google Maps ↗

Secondary Practice Location 1

Location 12150 Pennsylvania Ave NWWashington, DC 20037-3201 · Phone (202) 741-2222

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Wonseok William Choi is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID8426558727
PECOS Enrollment IDI20260819004130
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 Wonseok Choi reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Inova Health Care Services
402 mi
Diagnostic Radiology
11335 PEMBROOKE SQ STE 101
Waldorf, MD 20603
  • Reassigned Medicare billing, District of Columbia and Virginia enrollments
  • Also billed through NPI 1275097123 (District of Columbia)
  • 2,618 clinicians in this Medicare group
NPI 1851829550 (301) 932-4522

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.

Tufts Medical Center

Acute Care Hospitals · Boston, MA
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220116
Location800 Washington StreetBoston, MA 02111 · Suffolk County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 02111 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
$189.86 typical visit price
range $63.72 – $189.86
Typical copayment $47.46 (range $15.93 – $47.46)
Most-billed visit code 99205
Established Patient
$111.18 typical visit price
range $21.07 – $155.29
Typical copayment $27.79 (range $5.26 – $38.82)
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.

AARON DICKSTEIN M.D.
Internal Medicine (Gastroenterology)
800 WASHINGTON ST, BOX 233
BOSTON, MA 02111
Suffolk County (617) 636-5883
THOMAS E BIGELOW
Technician/Technologist (Optician)
800 WASHINGTON ST, BOX 450
BOSTON, MA 02111
Suffolk County (617) 636-5857
SARAH MERRIMAN PERSING M.D.
Plastic Surgery
800 WASHINGTON ST
BOSTON, MA 02111
Suffolk County (617) 636-5000
DR. SHARANYA MOHANTY M.D.
Internal Medicine
800 WASHINGTON ST
BOSTON, MA 02111
Suffolk County (617) 636-5000
AFRAH SADIQ SAIT MOHAMMED M.D.
Internal Medicine (Infectious Disease)
800 WASHINGTON ST
BOSTON, MA 02111
Suffolk County (718) 629-7204
ADNAN SALIM QAMAR MD
Student in an Organized Health Care Education/Training Program
800 WASHINGTON ST
BOSTON, MA 02111
Suffolk County (617) 636-5829
ALICIA SIGIA WU MD
Psychiatry & Neurology (Psychiatry)
800 WASHINGTON ST
BOSTON, MA 02111
Suffolk County (617) 636-1619
ZEANAARONEVAN ANDRES LUNA
Student in an Organized Health Care Education/Training Program
800 WASHINGTON ST
BOSTON, MA 02111
Suffolk County (617) 636-8100

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 Wonseok Choi's NPI number?

The NPI number for Wonseok Choi is 1801415781. It was assigned to this individual provider in the NPPES registry on April 10, 2020.

Where is Wonseok Choi located?

Wonseok Choi practices at 800 Washington St, Boston, MA 02111. The listed phone number is (617) 636-5000.

What is Wonseok Choi's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology & Oncology, with taxonomy code 207RH0003X.

Is Wonseok Choi enrolled in Medicare?

Yes. Wonseok Choi is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Wonseok Choi's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Wonseok Choi reassigns Medicare benefits to Inova Health Care Services (Waldorf, MD). 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 Wonseok Choi's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is Wonseok Choi affiliated with any hospitals?

According to CMS data, Wonseok Choi is affiliated with Tufts Medical Center.

When was this NPI record last updated?

The NPPES record for Wonseok Choi was last updated on June 22, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 years 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.