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DR. JEFFREY C MARK M.D.
NPI 1487603155
Internal Medicine - Gastroenterology in Turlock, CA

Active since May 09, 2006PECOS EnrolledAccepts Medicare Assignment
20.05/100
CMS Quality Rating
2101 GEER RD, SUITE #118, TURLOCK, CA 95382(209) 669-5000(209) 669-5001 Get Directions Write a Review

NPPES record last updated: July 13, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Dr. Jeffrey C Mark M.d. NPPES

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

DR. JEFFREY C MARK M.D. (NPI 1487603155) is an individual gastroenterology provider in Turlock, California, licensed in California (G83524) and active in the NPI registry since May 2006. He is enrolled in Medicare PECOS and is a graduate of University Of Illinois College Of Med (chi/peor/rock/chm-urb) (1992).

NPPES Registry Identity

NPI1487603155
Entity TypeIndividualMale
Primary Taxonomy207RG0100X
Provider Legal NameDR. JEFFREY C MARKCredential: M.D.
Location Address2101 GEER RD, SUITE #118Turlock, CA 95382-2454
Mailing Address2101 Geer Rd, Suite #118Turlock, CA 95382-2454 · (209) 669-5000 · Fax (209) 669-5001
Phone(209) 669-5000
Fax(209) 669-5001
Sole ProprietorNo
Medical School CMSUniversity Of Illinois College Of Med (chi/peor/rock/chm-urb)Graduated 1992
Enumeration DateMay 9, 2006
Last NPPES UpdateJuly 13, 2026
✔ NPI 1487603155 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · GastroenterologyAllopathic & Osteopathic Physicians
Taxonomy Code207RG0100X
License✔ Licensed in CA · G83524
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.
2101 GEER RD, Turlock, CA 95382
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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

Dr. Jeffrey C Mark 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 ID8628080421
PECOS Enrollment IDI20081201000681
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 Jeffrey Mark reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Adult & Pediatric Gastroenterology Medical Center
65 mi
Gastroenterology
111 DEERWOOD RD, SUITE 168
San Ramon, CA 94583
  • Reassigned Medicare billing, California enrollment
NPI 1538367818 (925) 736-8228

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 5

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.
670 services218 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.
69 services69 patients
Biopsy of large bowel using a flexible endoscope 45380
A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.
50 services50 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.
33 services31 patients
Removal of polyps or growths of large bowel using an endoscope with mechanical snare 45385
This procedure involves using a thin, flexible tube called an endoscope to examine the large bowel. If any abnormal growths or polyps are found, a tool called a mechanical snare is used to remove them. This is a common method to prevent potential health issues.
16 services15 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 95382 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
$133.94 typical visit price
range $58.87 – $176.60
Typical copayment $33.48 (range $14.71 – $44.15)
Most-billed visit code 99204
Established Patient
$103.36 typical visit price
range $19.28 – $144.60
Typical copayment $25.84 (range $4.82 – $36.15)
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.

20.05/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Individually scored
Quality0
Improvement Activities0
Cost66.86

Other Providers at the Same Location NPPES 16

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

MANPREET KAUR
Adult Companion
2101 GEER RD
TURLOCK, CA 95382
Stanislaus County (209) 664-8044
MRS. TANYA MARIE MANGUM L.C.S.W.
Social Worker (Clinical)
2101 GEER RD, STE. 120
TURLOCK, CA 95382
Stanislaus County (209) 664-8044
LEANN WESNER M.F.T.
Marriage & Family Therapist
2101 GEER RD, G - 304
TURLOCK, CA 95382
Stanislaus County (209) 509-7541
ASHLEY ANN BROWN
Marriage & Family Therapist
2101 GEER RD
TURLOCK, CA 95382
Stanislaus County (209) 326-9048
MRS. BERGEN FILGAS L.M.F.T.
Marriage & Family Therapist
2101 GEER RD
TURLOCK, CA 95382
Stanislaus County (209) 262-4387
MERCY WEST URGENT CARE INC
Emergency Medicine
2101 GEER RD, 108 AND 111
TURLOCK, CA 95382
Stanislaus County (209) 656-7100
KRISTY ANN JOHNSON LMFT
Marriage & Family Therapist
2101 GEER RD
TURLOCK, CA 95382
Stanislaus County (209) 664-8044
MS. ALICE A TAMRAZ BHS
Case Manager/Care Coordinator
2101 GEER RD, SUITE 120
TURLOCK, CA 95382
Stanislaus County (209) 664-8044

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 Jeffrey Mark's NPI number?

The NPI number for Jeffrey Mark is 1487603155. It was assigned to this individual provider in the NPPES registry on May 9, 2006.

Where is Jeffrey Mark located?

Jeffrey Mark practices at 2101 Geer Rd Suite #118, Turlock, CA 95382. The listed phone number is (209) 669-5000.

What is Jeffrey Mark's specialty?

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

Is Jeffrey Mark enrolled in Medicare?

Yes. Jeffrey Mark 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 Jeffrey Mark's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Jeffrey Mark reassigns Medicare benefits to Adult & Pediatric Gastroenterology Medical Center (San Ramon, 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 Jeffrey Mark'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 Jeffrey Mark was last updated on July 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.