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DR. MARY CHEN M.D.
NPI 1568445229
Internal Medicine in Walnut, CA

Active since November 26, 2005PECOS EnrolledAccepts Medicare Assignment
18780 AMAR RD, SUITE 107, WALNUT, CA 91789(626) 810-6777(626) 810-6687 Get Directions Write a Review

NPPES record last updated: April 23, 2020. Verified against the NPPES registry weekly; last sync: August 09, 2026.

About Dr. Mary Chen M.d. NPPES

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

DR. MARY CHEN M.D. (NPI 1568445229) is an individual internal medicine provider in Walnut, California, licensed in California (A78207) and active in the NPI registry since November 2005. She is enrolled in Medicare PECOS and is a graduate of Other (1985).

NPPES Registry Identity

NPI1568445229
Entity TypeIndividualFemale
Primary Taxonomy207R00000X
Provider Legal NameDR. MARY CHENCredential: M.D.
Location Address18780 AMAR RD, SUITE 107Walnut, CA 91789-4560
Mailing Address18780 Amar Rd, Suite 107Walnut, CA 91789-4560 · (626) 810-6777 · Fax (626) 810-6687
Phone(626) 810-6777
Fax(626) 810-6687
Sole ProprietorNo
Medical School CMSOtherGraduated 1985
Enumeration DateNovember 26, 2005
Last NPPES UpdateApril 23, 2020
NPPES CertifiedApril 23, 2020
✔ NPI 1568445229 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in CA · A78207
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.
Also ListedFamily MedicineTaxonomy 207Q00000X · License A78207 (CA)
18780 AMAR RD, Walnut, CA 91789
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Other Names 1

Former Name (1)Dr. Lei Chen M.d.

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

Dr. Mary Chen 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 ID7416929898
PECOS Enrollment IDI20040806000679
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 2

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.
153 services36 patients
Annual wellness visit, includes a personalized prevention plan of service (pps), subsequent visit G0439
An annual wellness visit is a yearly appointment with your primary care provider to create or update a personalized prevention plan. This plan helps prevent illness based on your current health and risk factors. It's a subsequent visit, meaning it follows an initial assessment.
19 services19 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 91789 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
$142.39 typical visit price
range $62.96 – $187.60
Typical copayment $35.59 (range $15.74 – $46.90)
Most-billed visit code 99204
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
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 6

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

ALMA FAMILY SERVICES
Community/Behavioral Health
18780 AMAR RD, SUITE 204
WALNUT, CA 91789
Los Angeles County (626) 965-4463
MARY CHEN MD INC
Internal Medicine
18780 AMAR RD, SUITE 107
WALNUT, CA 91789
Los Angeles County (626) 810-6777
ACCESS HOME HEALTH CARE, INC,.
Home Health
18780 AMAR RD, SUITE #201
WALNUT, CA 91789
Los Angeles County (626) 965-2084
MRS. AFRICA LIZETTE ARROYO B.A.
Counselor (Mental Health)
18780 AMAR RD, SUITE 204
WALNUT, CA 91789
Los Angeles County (626) 965-4463
ABLE HANDS INC.
Home Health
18780 AMAR RD, STE. 207
WALNUT, CA 91789
Los Angeles County (626) 965-2233
ERIKA ROBLES
Rehabilitation Practitioner
18780 AMAR RD, 204
WALNUT, CA 91789
Los Angeles County (626) 965-4463

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 Chen's NPI number?

The NPI number for Mary Chen is 1568445229. It was assigned to this individual provider in the NPPES registry on November 26, 2005. The provider is also known as Dr. Lei Chen M.D..

Where is Mary Chen located?

Mary Chen practices at 18780 Amar Rd Suite 107, Walnut, CA 91789. The listed phone number is (626) 810-6777.

What is Mary Chen's specialty?

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

Is Mary Chen enrolled in Medicare?

Yes. Mary Chen 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 Mary Chen was last updated on April 23, 2020. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.