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DR. CHARLES WILLIS CALLAHAN DO
NPI 1295823557
Pediatrics - Pediatric Pulmonology in Washington, DC

Active since October 11, 2006PECOS Enrolled
WALTER REED ARMY MEDICAL CENTER, WASHINGTON, DC 20907(202) 782-8397(202) 782-4914 Get Directions Write a Review

NPPES record last updated: October 11, 2023. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Dr. Charles Willis Callahan Do NPPES

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

DR. CHARLES WILLIS CALLAHAN DO (NPI 1295823557) is an individual pediatric pulmonology provider in Washington, District Of Columbia, licensed in Hawaii (DOS719) and active in the NPI registry since October 2006. He is enrolled in Medicare PECOS and maintains a secondary practice location in Baltimore.

NPPES Registry Identity

NPI1295823557
Entity TypeIndividualMale
Primary Taxonomy2080P0214X
Provider Legal NameDR. CHARLES WILLIS CALLAHANCredential: DO
Location AddressWALTER REED ARMY MEDICAL CENTERWashington, DC 20907-1234
Mailing Address13104 Collingwood TerraceSilver Spring, MD 20904-1234 · (202) 782-8397 · Fax (202) 782-4914
Phone(202) 782-8397
Fax(202) 782-4914
Sole ProprietorYes
Enumeration DateOctober 11, 2006
Last NPPES UpdateOctober 11, 2023
NPPES CertifiedOctober 11, 2023
✔ NPI 1295823557 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPediatrics · Pediatric PulmonologyAllopathic & Osteopathic Physicians
Taxonomy Code2080P0214X
License✔ Licensed in HI · DOS719
Definition
A pediatrician dedicated to the prevention and treatment of all respiratory diseases affecting infants, children and young adults. This specialist is knowledgeable about the growth and development of the lung, assessment of respiratory function in infants and children, and experienced in a variety of invasive and noninvasive diagnostic techniques.
WALTER REED ARMY MEDICAL CENTER, Washington, DC 20907
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Secondary Practice Location 1

Location 122 S Greene StBaltimore, MD 21201-1544 · Phone (667) 214-1916 · Fax (410) 225-9405

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Charles Willis Callahan Do 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 Charles Callahan reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

University Of Maryland Pediatric Associates, PA
34 mi
Clinical Medical Laboratory
120 SOUTH PENN STREET
Baltimore, MD 21201
  • Reassigned Medicare billing, Maryland enrollment
  • 172 clinicians in this Medicare group
NPI 1679685804 (410) 706-5181

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

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 Charles Callahan's NPI number?

The NPI number for Charles Callahan is 1295823557. It was assigned to this individual provider in the NPPES registry on October 11, 2006.

Where is Charles Callahan located?

Charles Callahan practices at Walter Reed Army Medical Center, Washington, DC 20907. The listed phone number is (202) 782-8397.

What is Charles Callahan's specialty?

The primary specialty registered for this NPI is Pediatrics, specializing in Pediatric Pulmonology, with taxonomy code 2080P0214X.

Is Charles Callahan enrolled in Medicare?

Yes. Charles Callahan is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Charles Callahan's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Charles Callahan reassigns Medicare benefits to University Of Maryland Pediatric Associates, PA (Baltimore, 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 Charles Callahan'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 Charles Callahan was last updated on October 11, 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.