Maria Quan, MD
NPI 1043281405 · Obstetrics & Gynecology Physician · San Ramon, CA
Enrolled with Medicare as Practitioner - Obstetrics/Gynecology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Maria Quan, MD is a Obstetrics & Gynecology Physician provider in San Ramon, CA (NPI 1043281405).
Provider details
- NPI number
- 1043281405
- Entity type
- Individual
- Primary specialty
- Obstetrics & Gynecology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- C143703 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure33% of score
20 yrs in NPPES registry
- Profile completeness33% of score
100% of core fields populated
- Practice footprint20% of score
3 documented practice locations
- Open Payments transparency13% of score
Has Open Payments disclosures (2024)
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$26 across 1 record (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (2)
- 20642 John DrCastro Valley, CA 94546-5103Phone: (510) 581-2559
- 1000 Vale Terrace DrVista, CA 92084-5218Phone: (760) 631-5000Fax: (760) 414-3702
Registry dates
- Enumerated
- 2006-02-01
- Last updated
- 2026-05-18
- Certified
- 2026-05-18
Frequently asked questions
- What is Maria Quan's NPI number?
- Maria Quan's National Provider Identifier (NPI) is 1043281405, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Maria Quan's specialty?
- Maria Quan is listed in the NPPES registry with a primary specialty of Obstetrics & Gynecology Physician (Allopathic & Osteopathic Physicians).
- Where is Maria Quan located?
- Maria Quan's practice location on file with NPPES is 11030 Bollinger Canyon Rd Ste 200, San Ramon, CA 94582-4826.
- What is Maria Quan's phone number?
- The practice phone number listed in the NPPES registry for Maria Quan is (925) 263-5583.
- Does Maria Quan accept Medicare?
- Maria Quan is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Maria Quan's NPI active?
- Yes — Maria Quan's NPI (1043281405) is active in the NPPES registry as of the last update on 2026-05-18.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.