Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Dr. Jonathan E Efron, M.D.
Surgery Physician in Baltimore, MD · enumerated 2005.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1538144647
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Registry record
Entity type Individual (Type 1)
Name Dr. Jonathan E Efron
Credential M.D.
Sex Male
Practice address 4940 Eastern Ave, Baltimore, MD, 21224
Phone (410) 550-0100
Enumeration date Dec 12, 2005
Last updated in NPPES Feb 10, 2014
Taxonomy & licenses
208C00000X Colon & Rectal Surgery Physician Allopathic & Osteopathic Physicians · License 33553 (AZ) Secondary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure.
About the MD credential
Other identifiers
| Identifier | Type | State | Issuer |
|---|---|---|---|
| 418309600 | Medicaid | MD | - |
| P00217762 | Other | AZ | RAILROAD MEDICARE |
| 912742 | Medicaid | AZ | - |
| 86080015085259A982 | Other | AZ | TRIWEST |
What is an NPI number?
A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.
Frequently asked questions
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Jonathan Efron?
Jonathan Efron is registered in NPPES with the primary taxonomy of Surgery Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Other providers at this practice address
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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2014-02-10.