NPPES file of Aug 9, 2026

Monica Guillen

Specialist · Union City, CA

Monica Guillen is a specialist with a practice address in Union City, California, and NPI 1932921244, issued on Oct 28, 2024. Check the license with the California board that licenses this profession; the federal record below is the public data PlainDoctor holds for this provider.

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

NPPES recordNPPES file of Aug 9, 2026
1932921244
Name
Monica Guillen
Primary taxonomy
Specialist 174400000X
Practice location
33456 Alvarado Niles RD, Union City, CA 94587
Phone
(510) 675-0600
Enumerated
Oct 28, 2024
Record last updated
Oct 28, 2024
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). A record is not a license: verify it with the state board.
Download card Updates feed

Also registered at 33456 Alvarado Niles RD

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

  1. Richard Anderson, PAPhysician Assistant1902508633
  2. Jessica Louie, RN, NPPsychiatric/Mental Health Nurse Practitioner1316762008
  3. Aubrey MartinezSpecialist1750268199
  4. Yvonne Mostajo Nguyen, RNRegistered Nurse1902783343
  5. Sarah Wickman Ezell, APRNNurse Practitioner1285365841

Verify Monica Guillen in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersWhich California board licenses this professionCheck 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
Find 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.

Specialist providers in California

There are 5,749 specialist records in California. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.

All 5,749 in California → Every provider in Union City →

Other specialist records in California

  1. Fatemeh Abbasi, PTVan Nuys, CA1558496760
  2. Erlinda Abcede, M.D.Cudahy, CA1831228675
  3. Maher Abdallah, M.D.Palm Springs, CA1205988011
  4. Farinaz AbdiSan Marcos, CA1063153963
  5. Mai Abe, LESanta Monica, CA1609405158
  6. Hamid Abedi, HEARING AID SPECIALISan Diego, CA1659410744
  7. Jonas AbellaSan Francisco, CA1679760938
  8. Shreedhar Abhyankar, M.D.Indio, CA1861530669
  9. Elaine AbichRiverside, CA1780458927
  10. Mussarat Abidi, MDLadera Ranch, CA1053307769

Common questions

What is Monica Guillen's NPI number?

Monica Guillen's National Provider Identifier (NPI) is 1932921244, issued on Oct 28, 2024. An NPI identifies a provider in billing; it is not a license.

Where is Monica Guillen located?

The NPPES record lists a practice address at 33456 Alvarado Niles RD, Union City, CA, 94587. Phone: (510) 675-0600. Providers update this record themselves, so call before visiting.

How can I verify Monica Guillen's license?

Search the California board that licenses this profession; the NPPES record confirms identity only.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

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.