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

JOHN K BYUN MD
NPI 1528487089
Radiology - Radiation Oncology in Stony Brook, NY

Active since April 14, 2014PECOS EnrolledAccepts Medicare Assignment
101 NICOLLS RD, STONY BROOK, NY 11794(631) 444-2325 Get Directions Write a Review

NPPES record last updated: August 11, 2026. Verified against the NPPES registry weekly; last sync: August 16, 2026.

Record update history: Aug 11, 2026, Nov 8, 2024, May 9, 2019 (3 updates tracked since 2019).

About John K Byun Md NPPES

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

JOHN K BYUN MD (NPI 1528487089) is an individual radiation oncology provider in Stony Brook, New York, licensed in New York (345605) and active in the NPI registry since April 2014. He is enrolled in Medicare PECOS, maintains 4 additional practice locations, and is a graduate of Other (2014).

NPPES Registry Identity

NPI1528487089
Entity TypeIndividualMale
Primary Taxonomy2085R0001X
Provider Legal NameJOHN K BYUNCredential: MD
Location Address101 NICOLLS RDStony Brook, NY 11794-0001
Mailing AddressPo Box 419033Boston, MA 02241-9033 · (631) 444-2325
Sole ProprietorNo
Medical School CMSOtherGraduated 2014
Enumeration DateApril 14, 2014
Last NPPES UpdateAugust 11, 20263 updates tracked since enumeration
NPPES CertifiedAugust 11, 2026
NPI 1528487089 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

Primary SpecialtyRadiology · Radiation OncologyAllopathic & Osteopathic Physicians
Taxonomy Code2085R0001X
Licenses Licensed in NY · 345605 Licensed in NJ · 25MA10129400 Licensed in CA · C197416 Licensed in MA · 281113
Definition
A radiologist who deals with the therapeutic applications of radiant energy and its modifiers and the study and management of disease, especially malignant tumors.
101 NICOLLS RD, Stony Brook, NY 11794

Secondary Practice Locations 4

Location 1300 Sierra College Dr Ste 150Grass Valley, CA 95945-5083 · Phone (530) 802-6400
Location 2195 Little Albany StNew Brunswick, NJ 08901-1914 · Phone (732) 253-3939
Location 33249 Oak Park AveBerwyn, IL 60402-3429 · Phone (708) 783-3403
Location 4300 Pasteur DrStanford, CA 94305-2200 · Phone (650) 723-4000

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

Enrolled in Medicare and accepts Medicare assignment

John K Byun Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID4486985173
PECOS Enrollment IDI20240719002320
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.

Areas of Expertise CMS Part B claims 11

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Calculation of radiation therapy dose 77300
Radiation therapy dose calculation is a process to determine the exact amount of radiation needed to treat a specific area in the body. This calculation helps ensure the treatment is effective while minimizing harm to healthy tissues. It's a key part of planning your radiation therapy.
312 services19 patients
Ct guidance for insertion of radiation therapy fields 77014
CT guidance for insertion of radiation therapy fields involves using a CT scan to accurately map the area of your body where radiation will be applied. This ensures the radiation targets only the necessary area, minimizing impact to healthy tissues.
179 services89 patients
Design and construction of complex radiation treatment device 77334
The design and construction of a complex radiation treatment device is a process where a specialized instrument is created. This device targets harmful cells with high-energy rays to destroy or damage them, while minimizing impact on healthy cells. This aids in treating conditions like cancer.
79 services19 patients
Stereoscopic x-ray guidance for localization of target volume for the delivery of radiation therapy G6002
Stereoscopic x-ray guidance is a technique used in radiation therapy. It involves taking multiple X-ray images from different angles to create a 3D picture of the area to be treated. This helps accurately pinpoint the exact location for radiation delivery, ensuring the therapy is as effective as possible.
54 services35 patients
Obtaining data needed to develop the optimal radiation treatment, 3 or more treatment areas or any number of treatment areas where special treatment is involved 77290
This procedure involves collecting necessary data to plan the best radiation treatment. It may cover 3 or more areas or any area requiring special attention. Data collection includes imaging scans and tests to understand the disease's extent and to tailor a precise, effective treatment plan.
21 services18 patients
Complex radiation therapy planning 77263
Complex radiation therapy planning is a process to determine the most effective way to deliver radiation to a specific area in your body. It involves detailed imaging to map your body's structure, allowing for precise targeting of cancer cells while sparing healthy tissue.
20 services18 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 11794 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
$203.53 typical visit price
range $67.40 – $203.53
Typical copayment $50.88 (range $16.85 – $50.88)
Most-billed visit code 99205
Established Patient
$83.44 typical visit price
range $21.66 – $164.45
Typical copayment $20.86 (range $5.41 – $41.11)
Most-billed visit code 99213
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.

Internal Medicine
101 NICOLLS RD
STONY BROOK, NY 11794
Internal Medicine (Gastroenterology)
101 NICOLLS RD
STONY BROOK, NY 11794
Social Worker (Clinical)
101 NICOLLS RD
STONY BROOK, NY 11794
Nurse Practitioner (Adult Health)
101 NICOLLS RD
STONY BROOK, NY 11794
Nurse Practitioner (Adult Health)
101 NICOLLS RD
STONY BROOK, NY 11794
Student in an Organized Health Care Education/Training Program
101 NICOLLS RD
STONY BROOK, NY 11794
Student in an Organized Health Care Education/Training Program
101 NICOLLS RD
STONY BROOK, NY 11794
Student in an Organized Health Care Education/Training Program
101 NICOLLS RD
STONY BROOK, NY 11794

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 John Byun's NPI number?

The NPI number for John Byun is 1528487089. It was assigned to this individual provider in the NPPES registry on April 14, 2014.

Where is John Byun located?

John Byun practices at 101 Nicolls Rd, Stony Brook, NY 11794. The listed phone number is (631) 444-2325.

What is John Byun's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Radiation Oncology, with taxonomy code 2085R0001X.

Is John Byun enrolled in Medicare?

Yes. John Byun is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

When was this NPI record last updated?

The NPPES record for John Byun was last updated on August 11, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.