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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 30 days.

DR. AUDREY LIYANG CHAI MD
NPI 1649807835
Internal Medicine in Palo Alto, CA

Active since March 26, 2020PECOS Enrolled
500 PASTEUR DR, PALO ALTO, CA 94304(650) 723-4000 Get Directions Write a Review

NPPES record last updated: July 20, 2026. Verified against the NPPES registry weekly; last sync: July 26, 2026.

Record update history: Jul 20, 2026, Jan 11, 2026, Mar 26, 2020 (3 updates tracked since 2020).

About Dr. Audrey Liyang Chai Md NPPES

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

DR. AUDREY LIYANG CHAI MD (NPI 1649807835) is an individual internal medicine provider in Palo Alto, California, licensed in California (186492) and active in the NPI registry since March 2020. She is enrolled in Medicare PECOS and maintains 2 additional practice locations.

NPPES Registry Identity

NPI1649807835
Entity TypeIndividualFemale
Primary Taxonomy207R00000X
Provider Legal NameDR. AUDREY LIYANG CHAICredential: MD
Location Address500 PASTEUR DRPalo Alto, CA 94304-1048
Mailing Address300 Pasteur DrStanford, CA 94305-2200
Phone(650) 723-4000
Sole ProprietorNo
Enumeration DateMarch 26, 2020
Last NPPES UpdateJuly 20, 20263 updates tracked since enumeration
NPPES CertifiedJuly 20, 2026
✔ NPI 1649807835 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in CA · 186492
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
500 PASTEUR DR, Palo Alto, CA 94304
Open in Google Maps ↗

Secondary Practice Locations 2

Location 1500 Pasteur DrPalo Alto, CA 94304-1048 · Phone (650) 723-4000
Location 21200 N State Street Clinic Tower, Suite A7DLos Angeles, CA 90033-1029 · Phone (323) 409-7556

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. Audrey Liyang Chai 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 94304 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
$156.67 typical visit price
range $70.37 – $206.04
Typical copayment $39.16 (range $17.59 – $51.51)
Most-billed visit code 99204
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.

DR. INDRANI GUZMAN DAS MD, MPH
Student in an Organized Health Care Education/Training Program
500 PASTEUR DR
PALO ALTO, CA 94304
Santa Clara County (650) 723-4000
CALLIE KIYONO VANWINKLE
Student in an Organized Health Care Education/Training Program
500 PASTEUR DR
PALO ALTO, CA 94304
Santa Clara County (650) 724-4750
DR. RAVNIT K. BHATIA DO
Internal Medicine (Geriatric Medicine)
500 PASTEUR DR
PALO ALTO, CA 94304
Santa Clara County (650) 723-4000
DIVYA RAMAKRISHNAN MD
Student in an Organized Health Care Education/Training Program
500 PASTEUR DR
PALO ALTO, CA 94304
Santa Clara County (650) 723-4000
HANS-CHRISTOPH RICHARD FREDERIK BECKER MD
Radiology (Diagnostic Radiology)
500 PASTEUR DR
PALO ALTO, CA 94304
Santa Clara County (650) 723-4000
JUDITH SUNAH KIM PHARMD
Pharmacist
500 PASTEUR DR
PALO ALTO, CA 94304
Santa Clara County (650) 723-8561
JON HOCHSTEIN
Student in an Organized Health Care Education/Training Program
500 PASTEUR DR
PALO ALTO, CA 94304
Santa Clara County (650) 723-5000
KIMBERLY MAY LAU PHARMD
Pharmacist (Oncology)
500 PASTEUR DR
PALO ALTO, CA 94304
Santa Clara County (415) 290-1588

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 Audrey Chai's NPI number?

The NPI number for Audrey Chai is 1649807835. It was assigned to this individual provider in the NPPES registry on March 26, 2020.

Where is Audrey Chai located?

Audrey Chai practices at 500 Pasteur Dr, Palo Alto, CA 94304. The listed phone number is (650) 723-4000.

What is Audrey Chai's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Audrey Chai enrolled in Medicare?

Yes. Audrey Chai is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for Audrey Chai was last updated on July 20, 2026. NPI Profile syncs with the weekly NPPES data releases published by CMS.