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MARY J TIERNEY NP
NPI 1245301571
Nurse Practitioner in San Mateo, CA

Active since November 10, 2006PECOS Enrolled
222 W 39TH AVE, SAN MATEO, CA 94403(650) 573-2222 Get Directions Write a Review

NPPES record last updated: July 8, 2007. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Mary J Tierney Np NPPES

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

MARY J TIERNEY NP (NPI 1245301571) is an individual nurse practitioner in San Mateo, California, licensed in California (NP8020) and active in the NPI registry since November 2006. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1245301571
Entity TypeIndividualFemale
Primary Taxonomy363L00000X
Provider Legal NameMARY J TIERNEYCredential: NP
Location Address222 W 39TH AVESan Mateo, CA 94403-4364
Mailing Address222 W 39th AveSan Mateo, CA 94403-4364 · (650) 573-2222
Phone(650) 573-2222
Sole ProprietorNo
Enumeration DateNovember 10, 2006
Last NPPES UpdateJuly 8, 2007
✔ NPI 1245301571 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363L00000X
License✔ Licensed in CA · NP8020
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.
222 W 39TH AVE, San Mateo, CA 94403
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Other Identifiers 3

Medicare UPINP17841CA
MedicaidRN210322CA
Medicare ID-Type UnspecifiedZZZ19237ZCA

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mary J Tierney Np 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 Mary Tierney reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

County Of San Mateo
Same address
Multi-Specialty
222 W 39TH AVE
San Mateo, CA 94403
  • Reassigned Medicare billing, California enrollment
  • Also billed through NPI 1114005105 (California)
  • 430 clinicians in this Medicare group
NPI 1831268580 (650) 573-3702

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

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94403 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
$104.51 typical visit price
range $69.00 – $202.35
Typical copayment $26.12 (range $17.25 – $50.58)
Most-billed visit code 99203
Established Patient
$119.48 typical visit price
range $23.44 – $166.46
Typical copayment $29.87 (range $5.86 – $41.61)
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.

DR. LORENA MICHEL PSY.D.
Psychologist (Clinical)
222 W 39TH AVE
SAN MATEO, CA 94403
San Mateo County (650) 573-3420
COUNTY OF SAN MATEO
General Acute Care Hospital
222 W 39TH AVE
SAN MATEO, CA 94403
San Mateo County (650) 573-2222
DR. JUDITH CLAIRE SCHIFFNER M.D.
Dermatology
222 W 39TH AVE
SAN MATEO, CA 94403
San Mateo County (650) 573-2414
SAN MATEO MEDICAL CENTER
Clinic/Center
222 W 39TH AVE
SAN MATEO, CA 94403
San Mateo County (650) 573-2222
JOHN ANDERSON MD
Obstetrics & Gynecology
222 W 39TH AVE
SAN MATEO, CA 94403
San Mateo County (650) 573-2222
MR. PAUL SAITO M.A.
Counselor
222 W 39TH AVE
SAN MATEO, CA 94403
San Mateo County (650) 573-3435
CHRISTIAN SUSTRINA PTA
Physical Medicine & Rehabilitation
222 W 39TH AVE
SAN MATEO, CA 94403
San Mateo County (650) 573-2222
KATHRYN JOY SANTANA RN PHN
Registered Nurse
222 W 39TH AVE
SAN MATEO, CA 94403
San Mateo County (650) 573-3982

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 Mary Tierney's NPI number?

The NPI number for Mary Tierney is 1245301571. It was assigned to this individual provider in the NPPES registry on November 10, 2006.

Where is Mary Tierney located?

Mary Tierney practices at 222 W 39th Ave, San Mateo, CA 94403. The listed phone number is (650) 573-2222.

What is Mary Tierney's specialty?

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

Is Mary Tierney enrolled in Medicare?

Yes. Mary Tierney is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Mary Tierney's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mary Tierney reassigns Medicare benefits to County Of San Mateo (San Mateo, CA). 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 Mary Tierney'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 Mary Tierney was last updated on July 8, 2007. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 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.