Leopoldo John Alonzo, MD
Obstetrics & Gynecology Physician · Fontana, CA
Leopoldo John Alonzo, MD is an obstetrics & gynecology physician with a practice address in Fontana, California, and NPI 1730306218, issued on Apr 19, 2007. Check the license (California G79776, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Leopoldo John Alonzo
- Credential
- MD
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License number
- G79776 CA
Self-reported in NPPES; status is on the state search - Practice location
- 9961 Sierra Ave, Fontana, CA 92335
- Phone
- (909) 427-3910
- Enumerated
- Apr 19, 2007
- Record last updated
- Sep 23, 2008 (not updated in 18 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
Also registered at 9961 Sierra Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Solomon Abila, MDFamily Medicine Physician1871652479
- Jenny Abouelsood, M.D.Family Medicine Physician1457638512
- Marla Abrolat, MDPediatrics Physician1164593133
- Eduardo Acosta, MDPediatrics Physician1497803324
- Michael Adair, MDFamily Medicine Physician1780732651
- Berneva Adams, MDObstetrics & Gynecology Physician1376602987
Verify Leopoldo John Alonzo in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G79776Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Industry payments in 2024: $80.00
1 payment: compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program; the largest payer was Abbvie Inc. The 21,429 providers of this specialty with any payment received $1,030.61 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
50 obstetrics & gynecology physician records list a practice address in Fontana
They are 50 of the 3,012 NPPES records with a practice address in Fontana, and 5,088 obstetrics & gynecology physician records in California.
All 50 in Fontana → All 5,088 in California → Every provider in Fontana →
Other obstetrics & gynecology physician records in California
- Ingrid Aalami, MDSan Jose, CA1952376550
- Avisa Abaian- Eagar, M.D.Orange, CA1316057755
- Derek Abbassi, MDWalnut Creek, CA1841364155
- Ahmed Abdelaziz, MDSanta Maria, CA1790039733
- Alireza Abdollah Shamshirsaz, M.D.Palo Alto, CA1881804235
- Nicole Abell, DOVentura, CA1811243603
- Zachary AbelsonLos Angeles, CA1689237414
- Ray Abinader, M.D.Loma Linda, CA1770901548
- Tarek Abou El Kheir, M.D.San Bernardino, CA1477521789
- Nada Abou-HaibaLos Angeles, CA1134067549
Common questions
What is Leopoldo John Alonzo, MD's NPI number?
Leopoldo John Alonzo, MD's National Provider Identifier (NPI) is 1730306218, issued on Apr 19, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Leopoldo John Alonzo, MD located?
The NPPES record lists a practice address at 9961 Sierra Ave, Fontana, CA, 92335. Phone: (909) 427-3910. Providers update this record themselves, so call before visiting.
How can I verify Leopoldo John Alonzo, MD's license?
NPPES lists California license number G79776, 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.