DR. JIUN YOON MD
NPI 1548258783
Allergy & Immunology in Ashburn, VA

Q: What is Jiun Yoon's NPI number?

The NPI number for Jiun Yoon is 1548258783. It was assigned to this individual provider in the NPPES registry on October 12, 2005.

Q: What is Jiun Yoon's specialty?

The primary specialty registered for this NPI is Allergy & Immunology with taxonomy code 207K00000X.

Q: When was this NPI record last updated?

The NPPES record for Jiun Yoon was last updated on January 20, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 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.

Active since October 12, 2005PECOS EnrolledAccepts Medicare Assignment

20955 PROFESSIONAL PLZ STE 300, ASHBURN, VA 20147(571) 246-6323(888) 823-5456 Get Directions Write a Review

NPPES record last updated: January 20, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Jan 20, 2026, Aug 24, 2018, Apr 27, 2018 and 1 more (4 updates tracked since 2015).

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About Dr. Jiun Yoon Md NPPES

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

DR. JIUN YOON MD (NPI 1548258783) is an individual allergy & immunology provider in Ashburn, Virginia, licensed in Virginia (0101246979) and active in the NPI registry since October 2005. He is enrolled in Medicare PECOS and is a graduate of Drexel University College Of Medicine (2001).

NPPES Registry Identity

NPI1548258783

Entity TypeIndividualMale

Primary Taxonomy207K00000X

Provider Legal NameDR. JIUN YOONCredential: MD

Location Address20955 PROFESSIONAL PLZ STE 300Ashburn, VA 20147

Mailing Address20955 Professional Plz Ste 300Ashburn, VA 20147-3405 · (571) 246-6323 · Fax (888) 823-5456

Phone(571) 246-6323

Fax(888) 823-5456

Sole ProprietorYes

Medical School CMSDrexel University College Of MedicineGraduated 2001

Enumeration DateOctober 12, 2005

Last NPPES UpdateJanuary 20, 20264 updates tracked since enumeration

NPPES CertifiedJanuary 20, 2026

✔ NPI 1548258783 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAllergy & ImmunologyAllopathic & Osteopathic Physicians

Taxonomy Code207K00000X

Licenses✔ Licensed in VA · 0101246979✔ Licensed in DC · MD038548✔ Licensed in MD · D70246

Definition

An allergist-immunologist is trained in evaluation, physical and laboratory diagnosis, and management of disorders involving the immune system. Selected examples of such conditions include asthma, anaphylaxis, rhinitis, eczema, and adverse reactions to drugs, foods, and insect stings as well as immune deficiency diseases (both acquired and congenital), defects in host defense, and problems related to autoimmune disease, organ transplantation, or malignancies of the immune system.

20955 PROFESSIONAL PLZ STE 300, Ashburn, VA 20147

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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 and accepts Medicare assignment

Dr. Jiun Yoon 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 ID5698939627

PECOS Enrollment IDI20140306000122

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 Jiun Yoon reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Ashburn Allergy, PLLC

Same address

Allergy & Immunology

20955 PROFESSIONAL PLZ STE 300
Ashburn, VA 20147

Reassigned Medicare billing, Virginia enrollment

NPI 1174039770 (571) 246-6323

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

Areas of Expertise CMS Part B claims

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.

New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203

This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.

15 services15 patients

Other Providers at the Same Location NPPES

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

ASHBURN ALLERGY, PLLC

Allergy & Immunology

20955 PROFESSIONAL PLZ STE 300
ASHBURN, VA 20147

Loudoun County (571) 246-6323

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 Jiun Yoon's NPI number?

The NPI number for Jiun Yoon is 1548258783. It was assigned to this individual provider in the NPPES registry on October 12, 2005.

Where is Jiun Yoon located?

Jiun Yoon practices at 20955 Professional Plz Ste 300, Ashburn, VA 20147. The listed phone number is (571) 246-6323.

What is Jiun Yoon's specialty?

The primary specialty registered for this NPI is Allergy & Immunology with taxonomy code 207K00000X.

Is Jiun Yoon enrolled in Medicare?

Yes. Jiun Yoon 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.

Which organization bills Medicare for Jiun Yoon's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Jiun Yoon reassigns Medicare benefits to Ashburn Allergy, PLLC (Ashburn, VA). 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 Jiun Yoon'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 Jiun Yoon was last updated on January 20, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 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.