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GRETL CHI-WING LAM M.D.
NPI 1184159253
Internal Medicine - Hospice and Palliative Medicine in Sunnyvale, CA

Active since April 26, 2017PECOS EnrolledAccepts Medicare Assignment
301 OLD SAN FRANCISCO RD, SUNNYVALE, CA 94086(408) 730-2860 Get Directions Write a Review

NPPES record last updated: September 22, 2025. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Nov 17, 2023, Jun 15, 2021, May 20, 2021 and 2 more (5 updates tracked since 2017).

About Gretl Chi-wing Lam M.d. NPPES

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

GRETL CHI-WING LAM M.D. (NPI 1184159253) is an individual hospice and palliative medicine provider in Sunnyvale, California, licensed in California (A203145) and active in the NPI registry since April 2017. She is enrolled in Medicare PECOS and is a graduate of New York University School Of Medicine (2017).

NPPES Registry Identity

NPI1184159253
Entity TypeIndividualFemale
Primary Taxonomy207RH0002X
Provider Legal NameGRETL CHI-WING LAMCredential: M.D.
Location Address301 OLD SAN FRANCISCO RDSunnyvale, CA 94086-6386
Mailing AddressPo Box 276950Sacramento, CA 95827-6950 · (507) 284-2511
Phone(408) 730-2860
Sole ProprietorNo
Medical School CMSNew York University School Of MedicineGraduated 2017
Enumeration DateApril 26, 2017
Last NPPES UpdateSeptember 22, 20255 updates tracked since enumeration
NPPES CertifiedSeptember 22, 2025
✔ NPI 1184159253 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Hospice and Palliative MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207RH0002X
License✔ Licensed in CA · A203145
Definition
An internal medicine physician with special knowledge and skills to prevent and relieve the suffering experienced by patients with life-limiting illnesses. This specialist works with an interdisciplinary hospice or palliative care team to maximize quality of life while addressing physical, psychological, social and spiritual needs of both patient and family throughout the course of the disease, through the dying process, and beyond for the family. This specialist has expertise in the assessment of patients with advanced disease; the relief of distressing symptoms; the coordination of interdisciplinary patient and family-centered care in diverse venues; the use of specialized care systems including hospice; the management of the imminently dying patient; and legal and ethical decision making in end-of-life care.
301 OLD SAN FRANCISCO RD, Sunnyvale, CA 94086
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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

Gretl Chi-wing Lam 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 ID840540423
PECOS Enrollment IDI20250919004092
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 Gretl Lam reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Sutter Bay Medical Foundation
8.7 mi
Multi-Specialty
795 EL CAMINO REAL
Palo Alto, CA 94301
  • Reassigned Medicare billing, California enrollment
  • 4,479 clinicians in this Medicare group
NPI 1013950807 (650) 321-4121

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 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.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233
Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.
41 services22 patients
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223
Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.
31 services30 patients

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. TAN MICHAEL NGUYEN MD
Internal Medicine
301 OLD SAN FRANCISCO RD
SUNNYVALE, CA 94086
Santa Clara County (408) 730-4360
MS. VAN T VU M.D.
Family Medicine
301 OLD SAN FRANCISCO RD
SUNNYVALE, CA 94086
Santa Clara County (408) 730-4262
AISHA AMIN
Internal Medicine
301 OLD SAN FRANCISCO RD
SUNNYVALE, CA 94086
Santa Clara County (718) 334-2488
MRS. CAM LINH FERNANDEZ NP
Nurse Practitioner
301 OLD SAN FRANCISCO RD
SUNNYVALE, CA 94086
Santa Clara County (408) 739-6000
DR. KIMBERLEY FAITH MA D.O
Family Medicine
301 OLD SAN FRANCISCO RD
SUNNYVALE, CA 94086
Santa Clara County (408) 730-4262
YUEN LAM SHEK LCSW
Social Worker (Clinical)
301 OLD SAN FRANCISCO RD
SUNNYVALE, CA 94086
Santa Clara County (408) 730-2800
BRANDON HSU DPT
Physical Therapist
301 OLD SAN FRANCISCO RD
SUNNYVALE, CA 94086
Santa Clara County (408) 523-3060
CAROLINE PHILIP NP
Nurse Practitioner (Family)
301 OLD SAN FRANCISCO RD
SUNNYVALE, CA 94086
Santa Clara County (408) 524-4116

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 Gretl Lam's NPI number?

The NPI number for Gretl Lam is 1184159253. It was assigned to this individual provider in the NPPES registry on April 26, 2017.

Where is Gretl Lam located?

Gretl Lam practices at 301 Old San Francisco Rd, Sunnyvale, CA 94086. The listed phone number is (408) 730-2860.

What is Gretl Lam's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hospice and Palliative Medicine, with taxonomy code 207RH0002X.

Is Gretl Lam enrolled in Medicare?

Yes. Gretl Lam 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 organization bills Medicare for Gretl Lam's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gretl Lam reassigns Medicare benefits to Sutter Bay Medical Foundation (Palo Alto, 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 Gretl Lam'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 Gretl Lam was last updated on September 22, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 months 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.