NPPES file of Aug 9, 2026

Allison Alden Merz-Herrala, MD

Obstetrics & Gynecology Physician · San Francisco, CA

Allison Alden Merz-Herrala, MD is an obstetrics & gynecology physician with a practice address in San Francisco, California, and NPI 1770112492, issued on Apr 4, 2020. Check the license (California A185547, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1770112492
Name
Allison Alden Merz-Herrala
Credential
MD
Primary taxonomy
Obstetrics & Gynecology Physician 207V00000X
License number
A185547 CA
Self-reported in NPPES; status is on the state search
Practice location
1001 Potrero Ave Bldg 5, San Francisco, CA 94110
Phone
(628) 206-3409
Enumerated
Apr 4, 2020
Record last updated
Jul 23, 2024
Fax
(415) 206-3112
Medicare enrollment
Enrolled (PECOS I20240802003309); accepts Medicare assignment
Medical or professional school
Harvard Medical School, 2020
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
Download card Updates feed

Also registered at 1001 Potrero Ave Bldg 5

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Mary Aiello, MAStudent in an Organized Health Care Education/Training Program1437934742
  2. Tatiana Baquero DevisClinical Social Worker1922842400
  3. Jack Buchanan, MD, PHDPsychiatry Physician1093343014
  4. Jon Farrell, ASWCommunity Health Worker1366118390
  5. Sheiphali Gandhi, M.D.Preventive Medicine/Occupational Environmental Medicine Physician1255692752
  6. Amanda Halpin, RN, NP, IBCLCAdult Health Nurse Practitioner1972875706

Verify Allison Alden Merz-Herrala in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license A185547
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

Is this page about you? You can ask us to correct, restrict or remove it: how.

Bills Medicare through one group practice

  1. University OF California Sfgh Medical GroupSan Francisco, CA

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Allison Alden Merz-Herrala among 5,088 obstetrics & gynecology physician records in California

Allison Alden Merz-Herrala, MD is one of 5,088 obstetrics & gynecology physician records with a practice address in California. 74% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2020, is newer than 94% of them.

  • NPI issued2020 · 94% of these records are older, 4% newer
  • In a Medicare fileYes · 74% of these records are
  • In the CMS Doctors and Clinicians fileYes · 53% of these records are
  • Graduated2020 · median 2004 among the 2,700 with a school on file
  • Record last updated2024 · 64% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207V00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Obstetrics & Gynecology Physician providers in California

There are 5,088 obstetrics & gynecology physician records in California.

The 8 obstetrics & gynecology physician records with the nearest ZIP codes

  1. Yamilee Bermingham, M.D.San Francisco, CA 941101013937127
  2. Deborah Cohan, MDSan Francisco, CA 941101831143221
  3. Craig Cohen, MDSan Francisco, CA 941101306889613
  4. Teresa Depineres, MDSan Francisco, CA 941101205880796
  5. Eleanor Drey, MDSan Francisco, CA 941101942254438
  6. Rebecca Jackson, MDSan Francisco, CA 941101699729640
  7. Vanessa Jacoby, MDSan Francisco, CA 941101154363778
  8. Barbara Nicol, M.D.San Francisco, CA 941101710907811

Common questions

What is Allison Alden Merz-Herrala, MD's NPI number?

Allison Alden Merz-Herrala, MD's National Provider Identifier (NPI) is 1770112492, issued on Apr 4, 2020. An NPI identifies a provider in billing; it is not a license.

Where is Allison Alden Merz-Herrala, MD located?

The NPPES record lists a practice address at 1001 Potrero Ave Bldg 5, San Francisco, CA, 94110. Phone: (628) 206-3409. Providers update this record themselves, so call before visiting.

How can I verify Allison Alden Merz-Herrala, MD's license?

NPPES lists California license number A185547, 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.

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.