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DR. DIANA MARIA MOKAYA M.D.
NPI 1023458528
Family Medicine in Union City, CA

Active since June 28, 2013PECOS Enrolled
33255 9TH ST, UNION CITY, CA 94587(510) 471-5880 Get Directions Write a Review

NPPES record last updated: May 5, 2026. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: May 5, 2026, Jun 1, 2023, Sep 7, 2021 (3 updates tracked since 2021).

About Dr. Diana Maria Mokaya M.d. NPPES

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

DR. DIANA MARIA MOKAYA M.D. (NPI 1023458528) is an individual family medicine provider in Union City, California, licensed in California (A133542) and active in the NPI registry since June 2013. She is enrolled in Medicare PECOS and maintains 2 additional practice locations.

NPPES Registry Identity

NPI1023458528
Entity TypeIndividualFemale
Primary Taxonomy207Q00000X
Provider Legal NameDR. DIANA MARIA MOKAYACredential: M.D.
Location Address33255 9TH STUnion City, CA 94587-2137
Mailing Address33255 9th StUnion City, CA 94587-2137 · (510) 471-5880
Phone(510) 471-5880
Sole ProprietorNo
Enumeration DateJune 28, 2013
Last NPPES UpdateMay 5, 20263 updates tracked since enumeration
NPPES CertifiedMay 5, 2026
✔ NPI 1023458528 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207Q00000X
License✔ Licensed in CA · A133542
Definition
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
33255 9TH ST, Union City, CA 94587
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Other Names 1

Former Name (1)Diana Maria Tucci

Secondary Practice Locations 2

Location 122331 Mission BlvdHayward, CA 94541-3911 · Phone (510) 471-5880
Location 216110 E 14th StAshland, CA 94578-3002 · Phone (510) 471-5880

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Diana Maria Mokaya M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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 Diana Mokaya reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Tiburcio Vasquez Health Center, Inc.
Same address
Federally Qualified Health Center (FQHC)
33255 9TH ST
Union City, CA 94587
  • Reassigned Medicare billing, California enrollment
  • 25 clinicians in this Medicare group
NPI 1851389696 (510) 471-5880

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 94587 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
$104.51 typical visit price
range $69.00 – $202.35
Typical copayment $26.12 (range $17.25 – $50.58)
Most-billed visit code 99203
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.

MONICA ZUNIGA M.A.
Counselor (Mental Health)
33255 9TH ST
UNION CITY, CA 94587
Alameda County (925) 336-6701
DR. ROXANA ELENA STANCESCU-POPESCU MD
Pediatrics
33255 9TH ST
UNION CITY, CA 94587
Alameda County (510) 471-5880
ALFREDO ENRIQUE ALVARADO
Community Health Worker
33255 9TH ST
UNION CITY, CA 94587
Alameda County (510) 471-5880
MARY DICOU FNP-C
Nurse Practitioner (Family)
33255 9TH ST
UNION CITY, CA 94587
Alameda County (510) 471-5880
JOANNE MARCELO
Nurse Practitioner (Family)
33255 9TH ST
UNION CITY, CA 94587
Alameda County (510) 471-5880
MRS. MADHUMITA BANERJEE ASW
Social Worker (Clinical)
33255 9TH ST
UNION CITY, CA 94587
Alameda County (510) 471-5880
MS. MARTHA VIRGINIA CLINE NP
Nurse Practitioner
33255 9TH ST
UNION CITY, CA 94587
Alameda County (510) 471-5880
MRS. VERONICA BOLTON ACEVEDO PA
Physician Assistant
33255 9TH ST
UNION CITY, CA 94587
Alameda County (510) 471-5880

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 Diana Mokaya's NPI number?

The NPI number for Diana Mokaya is 1023458528. It was assigned to this individual provider in the NPPES registry on June 28, 2013. The provider is also known as Diana Maria Tucci.

Where is Diana Mokaya located?

Diana Mokaya practices at 33255 9th St, Union City, CA 94587. The listed phone number is (510) 471-5880.

What is Diana Mokaya's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is Diana Mokaya enrolled in Medicare?

Yes. Diana Mokaya is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Diana Mokaya's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Diana Mokaya reassigns Medicare benefits to Tiburcio Vasquez Health Center, Inc. (Union City, 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 Diana Mokaya'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 Diana Mokaya was last updated on May 5, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.