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

MR. BRENDAN THOMAS MULLEN MD
NPI 1235657313
Internal Medicine - Infectious Disease in Seattle, WA

Active since September 08, 2017PECOS Enrolled
325 9TH AVE, SEATTLE, WA 98104(206) 520-5000 Get Directions Write a Review

NPPES record last updated: July 7, 2026. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Jul 7, 2026, Jun 15, 2021 (2 updates tracked since 2021).

About Mr. Brendan Thomas Mullen Md NPPES

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

MR. BRENDAN THOMAS MULLEN MD (NPI 1235657313) is an individual infectious disease provider in Seattle, Washington, licensed in Washington (MD.MD.60482538) and active in the NPI registry since September 2017. He is enrolled in Medicare PECOS and is a graduate of Other (2021).

NPPES Registry Identity

NPI1235657313
Entity TypeIndividualMale
Primary Taxonomy207RI0200X
Provider Legal NameMR. BRENDAN THOMAS MULLENCredential: MD
Location Address325 9TH AVESeattle, WA 98104-2420
Mailing AddressPo Box 50095Seattle, WA 98145-5095 · (206) 520-5700
Phone(206) 520-5000
Sole ProprietorNo
Medical School CMSOtherGraduated 2021
Enumeration DateSeptember 8, 2017
Last NPPES UpdateJuly 7, 20262 updates tracked since enumeration
NPPES CertifiedJuly 7, 2026
✔ NPI 1235657313 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Infectious DiseaseAllopathic & Osteopathic Physicians
Taxonomy Code207RI0200X
License✔ Licensed in WA · MD.MD.60482538
Definition
An internist who deals with infectious diseases of all types and in all organ systems. Conditions requiring selective use of antibiotics call for this special skill. This physician often diagnoses and treats AIDS patients and patients with fevers which have not been explained. Infectious disease specialists may also have expertise in preventive medicine and travel medicine.
325 9TH AVE, Seattle, WA 98104
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Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mr. Brendan Thomas Mullen Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID2062814668
PECOS Enrollment IDI20260526002595
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.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 98104 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
$143.76 typical visit price
range $63.67 – $189.37
Typical copayment $35.94 (range $15.91 – $47.34)
Most-billed visit code 99204
Established Patient
$111.00 typical visit price
range $21.12 – $155.00
Typical copayment $27.75 (range $5.28 – $38.75)
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.

SANDRA K WALKER ARNP
Nurse Practitioner (Acute Care)
325 9TH AVE
SEATTLE, WA 98104
King County (206) 598-0502
JULIA J VISSER DPT
Physical Therapist
325 9TH AVE, BOX 359920
SEATTLE, WA 98104
King County (206) 744-1675
GENIA J MONCADA
Pharmacist
325 9TH AVE, MAILSTOP 359912
SEATTLE, WA 98104
King County (206) 731-3219
JACQUELINE M. KIM LICSW, MSW
Social Worker (Clinical)
325 9TH AVE, BOX 359760
SEATTLE, WA 98104
King County (206) 744-8511
MS. DIANE E WHEELER MS, PA-C
Physician Assistant (Medical)
325 9TH AVE
SEATTLE, WA 98104
King County (206) 744-3000
AMELIA V. RIVERA
Physical Therapist
325 9TH AVE
SEATTLE, WA 98104
King County (206) 774-3300
TIMOTHY WILLIAM MENZA MD, PHD
Internal Medicine (Infectious Disease)
325 9TH AVE
SEATTLE, WA 98104
King County (206) 520-5000
DEMETRIOS TEREZAKIS
Occupational Therapist
325 9TH AVE
SEATTLE, WA 98104
King County (206) 744-6112

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 Brendan Mullen's NPI number?

The NPI number for Brendan Mullen is 1235657313. It was assigned to this individual provider in the NPPES registry on September 8, 2017.

Where is Brendan Mullen located?

Brendan Mullen practices at 325 9th Ave, Seattle, WA 98104. The listed phone number is (206) 520-5000.

What is Brendan Mullen's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Infectious Disease, with taxonomy code 207RI0200X.

Is Brendan Mullen enrolled in Medicare?

Yes. Brendan Mullen is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for Brendan Mullen was last updated on July 7, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 30 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.