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GREGORY FUNG MD
NPI 1700970795
Internal Medicine - Gastroenterology in San Francisco, CA

Active since October 03, 2006PECOS EnrolledAccepts Medicare Assignment
88.25/100
CMS Quality Rating
789 VALLEJO STREET, SAN FRANCISCO, CA 94133(415) 982-6691(415) 982-0914 Get Directions Write a Review

NPPES record last updated: December 11, 2008. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Gregory Fung Md NPPES

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

GREGORY FUNG MD (NPI 1700970795) is an individual gastroenterology provider in San Francisco, California, licensed in California (G41709) and active in the NPI registry since October 2006. He is enrolled in Medicare PECOS and is a graduate of University Of California, San Francisco School Of Medicine (1978).

NPPES Registry Identity

NPI1700970795
Entity TypeIndividualMale
Primary Taxonomy207RG0100X
Provider Legal NameGREGORY FUNGCredential: MD
Location Address789 VALLEJO STREETSan Francisco, CA 94133-3834
Mailing Address789 Vallejo StreetSan Francisco, CA 94133-3834 · (415) 982-6691 · Fax (415) 982-0914
Phone(415) 982-6691
Fax(415) 982-0914
Sole ProprietorNo
Medical School CMSUniversity Of California, San Francisco School Of MedicineGraduated 1978
Enumeration DateOctober 3, 2006
Last NPPES UpdateDecember 11, 2008
✔ NPI 1700970795 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License✔ Licensed in CA · G41709
Definition
An internist who specializes in diagnosis and treatment of diseases of the digestive organs including the stomach, bowels, liver and gallbladder. This specialist treats conditions such as abdominal pain, ulcers, diarrhea, cancer and jaundice and performs complex diagnostic and therapeutic procedures using endoscopes to visualize internal organs.
Also ListedInternal MedicineTaxonomy 207R00000X · License G41709 (CA)
789 VALLEJO STREET, San Francisco, CA 94133
Open in Google Maps ↗

Other Identifiers 2

Medicare UPINA48663
Medicare PIN00G417090CA

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

Gregory Fung Md 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 ID5799846168
PECOS Enrollment IDI20081203000520
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 Gregory Fung reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

City & County Of San Francisco
0.1 mi
Primary Care
1490 MASON ST
San Francisco, CA 94133
  • Reassigned Medicare billing, California enrollment
  • 1,573 clinicians in this Medicare group
NPI 1144263518 (415) 705-8500
San Francisco Digestive Disease Medical Group Inc A Prof Corp
2.7 mi
Gastroenterology
1 SHRADER ST STE 500
San Francisco, CA 94117
  • Reassigned Medicare billing, California enrollment
  • 3 clinicians in this Medicare group
NPI 1417017435 (415) 362-3336

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 8

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 low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
165 services81 patients
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232
Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.
68 services22 patients
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
59 services28 patients
Established patient office or other outpatient visit with straightforward medical decision making, if using time, 10 minutes or more 99212
This is a routine check-up for patients who have previously seen the doctor. During this 10-19 minute visit, the doctor will review your health status, discuss any concerns, and manage ongoing treatments or medications. It's a chance to ensure your health is on track.
24 services12 patients
Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43239
This procedure involves using a thin, flexible tube with a light and camera, known as an endoscope, to examine the esophagus, stomach, and upper part of the small intestine. Small tissue samples are taken for further examination to help diagnose various conditions.
21 services20 patients
Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222
Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.
17 services17 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94133 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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

88.25/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Quality83.33
Improvement Activities40
Cost73.74

Other Providers at the Same Location NPPES 2

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

GREGORY FUNG MD INC
Internal Medicine (Gastroenterology)
789 VALLEJO STREET
SAN FRANCISCO, CA 94133
San Francisco County (415) 982-6691
KENNETH D CHAN MD INC
Internal Medicine (Pulmonary Disease)
789 VALLEJO STREET
SAN FRANCISCO, CA 94133
San Francisco County (415) 982-6691

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 Gregory Fung's NPI number?

The NPI number for Gregory Fung is 1700970795. It was assigned to this individual provider in the NPPES registry on October 3, 2006.

Where is Gregory Fung located?

Gregory Fung practices at 789 Vallejo Street, San Francisco, CA 94133. The listed phone number is (415) 982-6691.

What is Gregory Fung's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.

Is Gregory Fung enrolled in Medicare?

Yes. Gregory Fung 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 Gregory Fung's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gregory Fung reassigns Medicare benefits to 2 organizations: City & County Of San Francisco (San Francisco, CA) and San Francisco Digestive Disease Medical Group Inc A Prof Corp (San Francisco, 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 Gregory Fung'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 Gregory Fung was last updated on December 11, 2008. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 17 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.