Maggie J. So, M.D.
Internal Medicine Physician · San Francisco, CA
Maggie J. So, M.D. is an internal medicine physician with a practice address in San Francisco, California, and NPI 1487887105, issued on Aug 27, 2009. Check the license (California A102991, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Maggie J. So
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A102991 CA
Self-reported in NPPES; status is on the state search - Practice location
- 2351 Clay St Ste 360, San Francisco, CA 94115
- Phone
- (415) 600-6000
- Enumerated
- Aug 27, 2009
- Record last updated
- Jul 3, 2013 (not updated in 13 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20100603000071); accepts Medicare assignment
- Medical or professional school
- New York Medical College, 2006
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 2351 Clay St Ste 360
A shared address usually means a shared clinic or building; it does not show who employs whom.
- David BowdenInternal Medicine Physician1164747671
- Jessica Lapasia, M.D.Internal Medicine Physician1457538522
Verify Maggie J. So in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A102991Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
98% fewer Medicare Part D claims than the average internal medicine physician in 2024
57 Medicare Part D claims for 24 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
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): 97.2 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
- Pacific Inpatient Medical GroupSan Francisco, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Maggie J. So among 17,696 internal medicine physician records in California
Maggie J. So, M.D. is one of 17,696 internal medicine physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2009, is newer than 60% of them.
- NPI issued2009 · 60% of these records are older, 37% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2006 · median 2004 among the 11,065 with a school on file
- Record last updated2013 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
1,318 internal medicine physician records list a practice address in San Francisco
They are 1,318 of the 38,143 NPPES records with a practice address in San Francisco, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in San Francisco → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Gary Arsham, M.D.San Francisco, CA 941151487646758
- Richard Caplin, M.D.San Francisco, CA 941151568443455
- C Cooney, M.D.San Francisco, CA 941151255332094
- Sarita Dubey, MDSan Francisco, CA 941151316905466
- Meredith Heller, M.D.San Francisco, CA 941151073562096
- Alan Leung, MDSan Francisco, CA 941151245222330
- Susan Nguyen, MDSan Francisco, CA 941151164470696
- Daniel Null, MDSan Francisco, CA 941151689638744
Common questions
What is Maggie J. So, M.D.'s NPI number?
Maggie J. So, M.D.'s National Provider Identifier (NPI) is 1487887105, issued on Aug 27, 2009. An NPI identifies a provider in billing; it is not a license.
Where is Maggie J. So, M.D. located?
The NPPES record lists a practice address at 2351 Clay St Ste 360, San Francisco, CA, 94115. Phone: (415) 600-6000. Providers update this record themselves, so call before visiting.
How can I verify Maggie J. So, M.D.'s license?
NPPES lists California license number A102991, as entered by the provider. 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 Maggie J. So, M.D. prescribe under Medicare Part D?
In 2024, Maggie J. So, M.D. had 57 Medicare Part D claims for 24 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is Maggie J. So, M.D.'s MIPS final score?
The 2023 MIPS final score is 97.2 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.