DR. GERALDINE GAN TAN MD
NPI 1699744086
Hospitalist in Walnut Creek, CA

Q: What is Geraldine Tan's NPI number?

The NPI number for Geraldine Tan is 1699744086. It was assigned to this individual provider in the NPPES registry on March 16, 2006.

Q: What is Geraldine Tan's specialty?

The primary specialty registered for this NPI is Hospitalist with taxonomy code 208M00000X.

Q: When was this NPI record last updated?

The NPPES record for Geraldine Tan was last updated on September 29, 2015. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.

Active since March 16, 2006PECOS Enrolled

1220 ROSSMOOR PKWY, WALNUT CREEK, CA 94595(925) 947-3393(925) 947-3396 Get Directions Write a Review

NPPES record last updated: September 29, 2015. Verified against the NPPES registry weekly; last sync: August 16, 2026.

On this page

About Dr. Geraldine Gan Tan Md NPPES

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

DR. GERALDINE GAN TAN MD (NPI 1699744086) is an individual hospitalist provider in Walnut Creek, California, licensed in California (A81859) and active in the NPI registry since March 2006. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1699744086

Entity TypeIndividualFemale

Primary Taxonomy208M00000X

Provider Legal NameDR. GERALDINE GAN TANCredential: MD

Location Address1220 ROSSMOOR PKWYWalnut Creek, CA 94595-2501

Mailing AddressDept 34929, P.o. Box 39000San Francisco, CA 94139-0001 · (925) 952-2828 · Fax (925) 952-2850

Phone(925) 947-3393

Fax(925) 947-3396

Sole ProprietorNo

Enumeration DateMarch 16, 2006

Last NPPES UpdateSeptember 29, 2015

✔ NPI 1699744086 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyHospitalistAllopathic & Osteopathic Physicians

Taxonomy Code208M00000X

License✔ Licensed in CA · A81859

Definition

Hospitalists are physicians whose primary professional focus is the general medical care of hospitalized patients. Their activities include patient care, teaching, research, and leadership related to Hospital Medicine. The term 'hospitalist' refers to physicians whose practice emphasizes providing care for hospitalized patients.

Also ListedInternal MedicineTaxonomy 207R00000X · License A81859 (CA)

1220 ROSSMOOR PKWY, Walnut Creek, CA 94595

Open in Google Maps ↗

Other Identifiers 6

Medicare PIN00A818590CA

Medicare PINCA147127CA

OtherP01495634CA · Railroad Medicare

Medicare UPING94561

Medicaid00A818590CA

Medicare PINP00180894CA

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Geraldine Gan Tan Md 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.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94595 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

$153.83 typical visit price

range $69.00 – $202.35

Typical copayment $38.45 (range $17.25 – $50.58)

Most-billed visit code 99204

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. ALI-REZA BARMAKI M.D.

Internal Medicine