Michael Duffy, DO
NPI 1851399802 · Internal Medicine Physician · San Diego, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Michael Duffy, DO is a Internal Medicine Physician provider in San Diego, CA (NPI 1851399802).
Provider details
- NPI number
- 1851399802
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- DO
- Sex
- Male
- Sole proprietor
- Yes
- License
- 20A9616 (CA)
Specialties & taxonomies
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
1 documented practice location
- 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.
$25 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
Registry dates
- Enumerated
- 2005-07-13
- Last updated
- 2022-09-22
- Certified
- 2022-09-22
Frequently asked questions
- What is Michael Duffy's NPI number?
- Michael Duffy's National Provider Identifier (NPI) is 1851399802, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Michael Duffy's specialty?
- Michael Duffy is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Michael Duffy located?
- Michael Duffy's practice location on file with NPPES is 1501 5th Ave Ste 100, San Diego, CA 92101-3251.
- What is Michael Duffy's phone number?
- The practice phone number listed in the NPPES registry for Michael Duffy is (619) 647-5072.
- Does Michael Duffy accept Medicare?
- Michael Duffy is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Michael Duffy's NPI active?
- Yes — Michael Duffy's NPI (1851399802) is active in the NPPES registry as of the last update on 2022-09-22.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.