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JAMES YENMING CHAO M.D.
NPI 1144455940
Internal Medicine - Cardiovascular Disease in Mountain View, CA

Active since May 22, 2009PECOS EnrolledAccepts Medicare Assignment
525 SOUTH DR STE 105, MOUNTAIN VIEW, CA 94040(650) 962-0242(650) 962-8657 Get Directions Write a Review

NPPES record last updated: April 15, 2024. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Apr 15, 2024, May 23, 2023, Oct 8, 2019 and 1 more (4 updates tracked since 2019).

About James Yenming Chao M.d. NPPES

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

JAMES YENMING CHAO M.D. (NPI 1144455940) is an individual cardiovascular disease provider in Mountain View, California, licensed in California (A118680) and active in the NPI registry since May 2009. He is enrolled in Medicare PECOS, maintains a secondary practice location in Stanford, and is a graduate of Oregon Health Sciences University School Of Medicine (2009).

NPPES Registry Identity

NPI1144455940
Entity TypeIndividualMale
Primary Taxonomy207RC0000X
Provider Legal NameJAMES YENMING CHAOCredential: M.D.
Location Address525 SOUTH DR STE 105Mountain View, CA 94040-4211
Mailing Address525 South Dr Ste 105Mountain View, CA 94040-4211 · (650) 962-0242 · Fax (650) 962-8657
Phone(650) 962-0242
Fax(650) 962-8657
Sole ProprietorYes
Medical School CMSOregon Health Sciences University School Of MedicineGraduated 2009
Enumeration DateMay 22, 2009
Last NPPES UpdateApril 15, 20244 updates tracked since enumeration
NPPES CertifiedApril 15, 2024
✔ NPI 1144455940 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 4

★ Primary SpecialtyInternal Medicine · Cardiovascular DiseaseAllopathic & Osteopathic Physicians
Taxonomy Code207RC0000X
License✔ Licensed in CA · A118680
Definition
An internist who specializes in diseases of the heart and blood vessels and manages complex cardiac conditions such as heart attacks and life-threatening, abnormal heartbeat rhythms.
Also ListedInternal MedicineTaxonomy 207R00000X · License A118680 (CA)
Also ListedInternal Medicine · Interventional CardiologyTaxonomy 207RI0011X · License A118680 (CA)
Also ListedNuclear Medicine · Nuclear CardiologyTaxonomy 207UN0901X · License A118680 (CA)
525 SOUTH DR STE 105, Mountain View, CA 94040
Open in Google Maps ↗

Secondary Practice Location 1

Location 1300 Pasteur DrStanford, CA 94305-2200 · Phone (650) 723-4000

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

James Yenming Chao M.d. 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 ID8325369010
PECOS Enrollment IDI20150605002713
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 Reassignments

2

Medicare enrollment records show James Chao reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Provider Profile
Same address
Cardiovascular Disease
525 SOUTH DRIVE, SUITE 105
Mountain View, CA 94040
  • Reassigned Medicare billing, California enrollment
NPI 1992891493 (650) 962-0242
Stanford Health Care
6.8 mi
General Acute Care Hospital
300 PASTEUR DRIVE
Stanford, CA 94305
  • Reassigned Medicare billing, California enrollment
  • 4,258 clinicians in this Medicare group
NPI 1437292927 (650) 723-4000

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

Areas of Expertise CMS Part B claims 6

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 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.
318 services198 patients
Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 93000
An electrocardiogram (ECG) is a non-invasive test that records your heart's electrical activity. Using 12 leads attached to your body, it captures data to help identify heart conditions. A doctor interprets the results and provides a report.
247 services194 patients
Ultrasound of heart with color-depicted blood flow, rate, direction and valve function 93306
This is a heart ultrasound, also known as an echocardiogram. It uses sound waves to create pictures of your heart, showing how blood flows through it. The color depicts the blood flow's speed and direction. It also checks the heart's valves to ensure they're working properly.
244 services193 patients
Ultrasound of both sides of head and neck blood flow 93880
An ultrasound of the head and neck blood flow is a safe, non-invasive procedure that uses sound waves to create images of blood vessels. It helps detect abnormalities like blockages or clots, ensuring optimal blood flow.
239 services192 patients
Ultrasound of heart with continuous electrocardiogram (ecg) during rest, exercise and/or drug induced stress with review and report 93351
This procedure involves using ultrasound technology to create images of your heart while you rest, exercise, or undergo drug-induced stress. An ECG continuously monitors your heart's electrical activity. It helps doctors assess heart health and function.
83 services79 patients
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204
This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.
40 services40 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94040 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
$86.56 typical visit price
range $23.96 – $169.60
Typical copayment $21.64 (range $5.99 – $42.40)
Most-billed visit code 99213
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

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

JOSEPH C. CHAO, M.D. CARDIOLOGY CLINIC
Internal Medicine (Cardiovascular Disease)
525 SOUTH DR STE 105
MOUNTAIN VIEW, CA 94040
Santa Clara County (650) 962-0242

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 James Chao's NPI number?

The NPI number for James Chao is 1144455940. It was assigned to this individual provider in the NPPES registry on May 22, 2009.

Where is James Chao located?

James Chao practices at 525 South Dr Ste 105, Mountain View, CA 94040. The listed phone number is (650) 962-0242.

What is James Chao's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Cardiovascular Disease, with taxonomy code 207RC0000X.

Is James Chao enrolled in Medicare?

Yes. James Chao 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.

Which organizations bill Medicare for James Chao's services?

According to the CMS Revalidation Reassignment List (October 2026 release), James Chao reassigns Medicare benefits to 2 organizations: (Mountain View, CA) and Stanford Health Care (Stanford, CA). Each 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 James Chao'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 James Chao was last updated on April 15, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.