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MALLORY ERIN FRANCES CALLAHAN NP
NPI 1528778214
Nurse Practitioner in Stanford, CA

Active since December 02, 2022PECOS EnrolledAccepts Medicare Assignment
300 PASTEUR DR, STANFORD, CA 94305(650) 723-4000 Get Directions Write a Review

NPPES record last updated: December 30, 2025. Verified against the NPPES registry weekly; last sync: September 06, 2026.

Record update history: Dec 30, 2025, Feb 6, 2023, Dec 16, 2022 and 1 more (4 updates tracked since 2022).

About Mallory Erin Frances Callahan Np NPPES

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

MALLORY ERIN FRANCES CALLAHAN NP (NPI 1528778214) is an individual nurse practitioner in Stanford, California, licensed in California (95023364) and active in the NPI registry since December 2022. She is enrolled in Medicare PECOS, maintains a secondary practice location in Redwood City, and is a graduate of Other (2022).

NPPES Registry Identity

NPI1528778214
Entity TypeIndividualFemale
Primary Taxonomy363L00000X
Provider Legal NameMALLORY ERIN FRANCES CALLAHANCredential: NP
Location Address300 PASTEUR DRStanford, CA 94305-2200
Mailing Address300 Pasteur DrStanford, CA 94305-2200 · (650) 723-4000
Phone(650) 723-4000
Sole ProprietorNo
Medical School CMSOtherGraduated 2022
Enumeration DateDecember 2, 2022
Last NPPES UpdateDecember 30, 20254 updates tracked since enumeration
NPPES CertifiedDecember 30, 2025
✔ NPI 1528778214 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 3

★ Primary SpecialtyNurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363L00000X
License✔ Licensed in CA · 95023364
Definition
(1) A registered nurse provider with a graduate degree in nursing prepared for advanced practice involving independent and interdependent decision making and direct accountability for clinical judgment across the health care continuum or in a certified specialty. (2) A registered nurse who has completed additional training beyond basic nursing education and who provides primary health care services in accordance with state nurse practice laws or statutes. Tasks performed by nurse practitioners vary with practice requirements mandated by geographic, political, economic, and social factors. Nurse practitioner specialists include, but are not limited to, family nurse practitioners, gerontological nurse practitioners, pediatric nurse practitioners, obstetric-gynecologic nurse practitioners, and school nurse practitioners.
Also ListedNurse Practitioner · Adult HealthTaxonomy 363LA2200X · License 95023364 (CA)
Also ListedNurse Practitioner · GerontologyTaxonomy 363LG0600X · License 95023364 (CA)
300 PASTEUR DR, Stanford, CA 94305
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Secondary Practice Location 1

Location 1420 Broadway StRedwood City, CA 94063-3132 · Phone (650) 736-5555

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

Mallory Erin Frances Callahan Np 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 ID42680241
PECOS Enrollment IDI20230104002379
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 5

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.

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
120 services102 patients
Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
93 services89 patients
Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215
This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.
77 services72 patients
Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 99231
Follow-up hospital inpatient care is a daily service where a healthcare professional checks on your health progress during your hospital stay. Each session typically lasts 15 minutes, involving updates on your condition and adjustments to your treatment plan, if necessary.
43 services30 patients
Established patient office or other outpatient visit with straightforward medical decision making, if using time, 10 minutes or more 99212
This is a routine check-up for patients who have previously seen the doctor. During this 10-19 minute visit, the doctor will review your health status, discuss any concerns, and manage ongoing treatments or medications. It's a chance to ensure your health is on track.
25 services22 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94305 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
$106.47 typical visit price
range $70.37 – $206.04
Typical copayment $26.61 (range $17.59 – $51.51)
Most-billed visit code 99203
Established Patient
$121.77 typical visit price
range $23.96 – $169.60
Typical copayment $30.44 (range $5.99 – $42.40)
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.

PRISTA CHARUWORN MD
Internal Medicine (Gastroenterology)
300 PASTEUR DR, ALWAY BUILD M211, MC 5187
STANFORD, CA 94305
Santa Clara County (650) 723-6661
ANDREW CHARLES PICEL M.D
Radiology (Vascular & Interventional Radiology)
300 PASTEUR DR
STANFORD, CA 94305
Santa Clara County (650) 723-4000
MATTHEW A WRIGHT M.D. PH.D.
Psychiatry & Neurology (Psychiatry)
300 PASTEUR DR
STANFORD, CA 94305
Santa Clara County (650) 723-4000
DR. QUAZI ZUBAIR AL-TARIQ M.D.
Radiology (Diagnostic Radiology)
300 PASTEUR DR
STANFORD, CA 94305
Santa Clara County (650) 723-4000
ANGIE DEE MURKINS NP
Nurse Practitioner
300 PASTEUR DR
STANFORD, CA 94305
Santa Clara County (650) 723-4000
DR. JAMSHID GHAJAR MD PHD
Neurological Surgery
300 PASTEUR DR
STANFORD, CA 94305
Santa Clara County (650) 723-4000
SARA BAKHTARY M.D.
Pathology (Anatomic Pathology & Clinical Pathology)
300 PASTEUR DR, LANE 235
STANFORD, CA 94305
Santa Clara County (650) 723-5252
YU KUANG LAI MD
Internal Medicine (Critical Care Medicine)
300 PASTEUR DR
STANFORD, CA 94305
Santa Clara County (650) 723-4000

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 Mallory Callahan's NPI number?

The NPI number for Mallory Callahan is 1528778214. It was assigned to this individual provider in the NPPES registry on December 2, 2022.

Where is Mallory Callahan located?

Mallory Callahan practices at 300 Pasteur Dr, Stanford, CA 94305. The listed phone number is (650) 723-4000.

What is Mallory Callahan's specialty?

The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.

Is Mallory Callahan enrolled in Medicare?

Yes. Mallory Callahan 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 Mallory Callahan was last updated on December 30, 2025. 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.