Taejoon Ahn, M.D.
NPI 1639198757 · Family Medicine Physician · Walnut Creek, CA
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Taejoon Ahn, M.D. is a Family Medicine Physician provider in Walnut Creek, CA (NPI 1639198757).
Provider details
- NPI number
- 1639198757
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- A67062 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
1,441 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. 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.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Admn Sarscov2 Vacc 1 Dose90480 | 832 | $52 |
| Administration of Influenza Virus VaccineG0008 | 609 | $39 |
Typical Medicare-allowed amounts for these services range $39–$52 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-07-19
- Last updated
- 2012-06-17
Frequently asked questions
- What is Taejoon Ahn's NPI number?
- Taejoon Ahn's National Provider Identifier (NPI) is 1639198757, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Taejoon Ahn's specialty?
- Taejoon Ahn is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Taejoon Ahn located?
- Taejoon Ahn's practice location on file with NPPES is 1455 Montego, Walnut Creek, CA 94598-2990.
- What is Taejoon Ahn's phone number?
- The practice phone number listed in the NPPES registry for Taejoon Ahn is (925) 939-4444.
- Does Taejoon Ahn accept Medicare?
- Taejoon Ahn is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Taejoon Ahn's NPI active?
- Yes — Taejoon Ahn's NPI (1639198757) is active in the NPPES registry as of the last update on 2012-06-17.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.