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DR. JOHN WESLEY PATRESAN MD
NPI 1023644978
Internal Medicine - Hematology & Oncology in Martinez, CA

Active since March 22, 2020PECOS Enrolled
2500 ALHAMBRA AVE, MARTINEZ, CA 94553(925) 370-5000 Get Directions Write a Review

NPPES record last updated: August 8, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Aug 8, 2026, Mar 22, 2020 (2 updates tracked since 2020).

About Dr. John Wesley Patresan Md NPPES

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

DR. JOHN WESLEY PATRESAN MD (NPI 1023644978) is an individual hematology & oncology provider in Martinez, California, licensed in California (A205802) and active in the NPI registry since March 2020. He is enrolled in Medicare PECOS and is a graduate of Other (2020).

NPPES Registry Identity

NPI1023644978
Entity TypeIndividualMale
Primary Taxonomy207RH0003X
Provider Legal NameDR. JOHN WESLEY PATRESANCredential: MD
Location Address2500 ALHAMBRA AVEMartinez, CA 94553-3156
Mailing Address2500 Alhambra AveMartinez, CA 94553-3156 · (209) 207-4069
Phone(925) 370-5000
Sole ProprietorNo
Medical School CMSOtherGraduated 2020
Enumeration DateMarch 22, 2020
Last NPPES UpdateAugust 8, 20262 updates tracked since enumeration
NPPES CertifiedAugust 8, 2026
✔ NPI 1023644978 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Hematology & OncologyAllopathic & Osteopathic Physicians
Taxonomy Code207RH0003X
License✔ Licensed in CA · A205802
Definition
An internist doctor of osteopathy that specializes in the treatment of the combination of hematology and oncology disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine WAS able to obtain a Certificate of Special Qualifications in the field of Hematology and Oncology. The Certificate is NO longer offered.
2500 ALHAMBRA AVE, Martinez, CA 94553
Open in Google Maps ↗

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. John Wesley Patresan Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID2668827668
PECOS Enrollment IDI20260713000809
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 John Patresan reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Contra Costa County
Same address
General Acute Care Hospital
2500 ALHAMBRA AVE
Martinez, CA 94553
  • Reassigned Medicare billing, California enrollment
  • 530 clinicians in this Medicare group
NPI 1386719086 (925) 370-5955

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

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94553 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
$202.35 typical visit price
range $69.00 – $202.35
Typical copayment $50.58 (range $17.25 – $50.58)
Most-billed visit code 99205
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.

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.

JOHN S HAWKINS
Family Medicine
2500 ALHAMBRA AVE
MARTINEZ, CA 94553
Contra Costa County (925) 370-5200
HYAEJEEN JEON
Student in an Organized Health Care Education/Training Program
2500 ALHAMBRA AVE
MARTINEZ, CA 94553
Contra Costa County (925) 370-5117
RONALD POWER DDS
Dentist
2500 ALHAMBRA AVE
MARTINEZ, CA 94553
Contra Costa County (925) 370-5110
DR. SARA JOSEPHINE RICHEY-LUCERO M.D.
General Practice
2500 ALHAMBRA AVE
MARTINEZ, CA 94553
Contra Costa County (925) 370-5182
CHARLOTTE STANDEFER
Family Medicine
2500 ALHAMBRA AVE
MARTINEZ, CA 94553
Contra Costa County (925) 370-5110
RICHARD NAGLE
Surgery
2500 ALHAMBRA AVE
MARTINEZ, CA 94553
Contra Costa County (925) 370-5110
CHRISTIAN MICHAEL EISERT MD, MPH
Otolaryngology
2500 ALHAMBRA AVE
MARTINEZ, CA 94553
Contra Costa County (925) 370-5000
ZOHAIB ABBASI
Psychiatry & Neurology (Psychiatry)
2500 ALHAMBRA AVE, PES
MARTINEZ, CA 94553
Contra Costa County (415) 409-9492

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 John Patresan's NPI number?

The NPI number for John Patresan is 1023644978. It was assigned to this individual provider in the NPPES registry on March 22, 2020.

Where is John Patresan located?

John Patresan practices at 2500 Alhambra Ave, Martinez, CA 94553. The listed phone number is (925) 370-5000.

What is John Patresan's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology & Oncology, with taxonomy code 207RH0003X.

Is John Patresan enrolled in Medicare?

Yes. John Patresan is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for John Patresan's services?

According to the CMS Revalidation Reassignment List (October 2026 release), John Patresan reassigns Medicare benefits to Contra Costa County (Martinez, 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 John Patresan'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 John Patresan was last updated on August 8, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.