Ji Won Ahn, MD
MOHS-Micrographic Surgery Physician · Walnut Creek, CA
Ji Won Ahn, MD is a mohs-micrographic surgery physician with a practice address in Walnut Creek, California, and NPI 1023460243, issued on Jul 12, 2016. Check the license on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Ji Won Ahn
- Credential
- MD
- Primary taxonomy
- MOHS-Micrographic Surgery Physician 207ND0101X
- License number
- 66941 MN
Self-reported in NPPES; status is on the state search - Practice location
- 320 Lennon LN Dept OF, Walnut Creek, CA 94598
- Phone
- (925) 817-5678
- Enumerated
- Jul 12, 2016
- Record last updated
- Oct 30, 2024
- Medicare enrollment
- Enrolled (PECOS I20241029002314); accepts Medicare assignment
- Medical or professional school
- Washington University School Of Medicine, 2016
- Entity
- Type 1 · individual
8 nearest mohs-micrographic surgery physician records → All 164 in California → Look up another NPI →
Verify Ji Won Ahn in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of CaliforniaCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
65% fewer Medicare Part D claims than the average mohs-micrographic surgery physician in 2024
202 Medicare Part D claims for 128 beneficiaries, against an average of 570 among the 1,396 providers of this specialty who prescribed in Part D. Brand-name drugs were 0% of claims. 12 claims were for opioids.
Most prescribed
- Mupirocin72 claims
- Cefadroxil64 claims
- Doxycycline Hyclate21 claims
- Tramadol Hcl12 claims
- Fluorouracil11 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The practice group's MIPS final score for 2023 (Medicare payment program): 77.5 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Permanente Medical Group IncWalnut Creek, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Ji Won Ahn among 164 mohs-micrographic surgery physician records in California
Ji Won Ahn, MD is one of 164 mohs-micrographic surgery physician records with a practice address in California. 95% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2016, is newer than 85% of them.
- NPI issued2016 · 85% of these records are older, 9% newer
- In a Medicare fileYes · 95% of these records are
- In the CMS Doctors and Clinicians fileYes · 87% of these records are
- Graduated2016 · median 2004 among the 143 with a school on file
- Record last updated2024 · 52% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207ND0101X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
MOHS-Micrographic Surgery Physician providers in California
There are 164 mohs-micrographic surgery physician records in California.
All 164 in California → Every provider in Walnut Creek → MOHS-Micrographic Surgery Physician nationwide →
The 8 mohs-micrographic surgery physician records with the nearest ZIP codes
- Jeffrey Bortz, M.D.Walnut Creek, CA 945981710191382
- Heather Nudo, PAWalnut Creek, CA 945981518077411
- Kathleen Ting, MDWalnut Creek, CA 945981407934599
- John Geisse, M.D.Vallejo, CA 945901275571028
- Joshua Spanogle, M.D.Vallejo, CA 945901750564407
- Lauren Gebauer, M.D.Napa, CA 945591386960961
- Kathryn Kent, MDNapa, CA 945581811159387
- Sumaira Aasi, MDStanford, CA 943051780675181
Common questions
What is Ji Won Ahn, MD's NPI number?
Ji Won Ahn, MD's National Provider Identifier (NPI) is 1023460243, issued on Jul 12, 2016. An NPI identifies a provider in billing; it is not a license.
Where is Ji Won Ahn, MD located?
The NPPES record lists a practice address at 320 Lennon LN Dept OF, Walnut Creek, CA, 94598. Phone: (925) 817-5678. Providers update this record themselves, so call before visiting.
How can I verify Ji Won Ahn, MD's license?
Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Ji Won Ahn, MD prescribe under Medicare Part D?
In 2024, Ji Won Ahn, MD had 202 Medicare Part D claims for 128 beneficiaries; the average among mohs-micrographic surgery physician prescribers was 570. Part D covers Medicare prescriptions only.
What is Ji Won Ahn, MD's MIPS final score?
The 2023 MIPS final score is 77.5 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.