Mark A. Illfelder, DO
Internal Medicine Physician · York, PA
Mark A. Illfelder, DO is an internal medicine physician with a practice address in York, Pennsylvania, and NPI 1568438869, issued on Feb 27, 2006. Check the license (Pennsylvania OS003803L, as entered in NPPES) on the Pennsylvania Department of State (PALS); the federal record below is the public data PlainDoctor holds for this provider.
- Name
- Mark A. Illfelder
- Credential
- DO
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- OS003803L PA
Self-reported in NPPES; status is on the state search - Practice location
- 1777 5TH Ave, York, PA 17403
- Phone
- (717) 843-8051
- Enumerated
- Feb 27, 2006
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Fax
- (717) 846-0721
- Medicaid ID
- 000759688 PA
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 7,300 in Pennsylvania → Look up another NPI →
Also registered at 1777 5TH Ave
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Verify Mark A. Illfelder in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersPennsylvania Department of State (PALS)
Search for license OS003803LCheck the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Mark A. Illfelder among 7,300 internal medicine physician records in Pennsylvania
Mark A. Illfelder, DO is one of 7,300 internal medicine physician records with a practice address in Pennsylvania. 78% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does not. Its NPI, issued in 2006, is newer than 9% of them.
- NPI issued2006 · 9% of these records are older, 64% newer
- In a Medicare fileNo · 78% of these records are
- In the CMS Doctors and Clinicians fileNo · 58% of these records are
- Record last updated2007 · 56% 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 Pennsylvania practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
164 internal medicine physician records list a practice address in York
They are 164 of the 4,575 NPPES records with a practice address in York, and 7,300 internal medicine physician records in Pennsylvania. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.
All 7,300 in Pennsylvania → Every provider in York → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Cyrus Beekey, MDYork, PA 174031972539336
- Todd Butz, MDYork, PA 174031477589026
- Robert Fritz, DOYork, PA 174031003882135
- Benjamin Hoover, M.D.York, PA 174031346272416
- Thomas Kurland, DOYork, PA 174031679549901
- W Leedy, DOYork, PA 174031235105115
- Bonny Lightner, DOYork, PA 174031902872187
- Cathy Manning, DOYork, PA 174031790715118
Common questions
What is Mark A. Illfelder, DO's NPI number?
Mark A. Illfelder, DO's National Provider Identifier (NPI) is 1568438869, issued on Feb 27, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Mark A. Illfelder, DO located?
The NPPES record lists a practice address at 1777 5TH Ave, York, PA, 17403. Phone: (717) 843-8051. Providers update this record themselves, so call before visiting.
How can I verify Mark A. Illfelder, DO's license?
NPPES lists Pennsylvania license number OS003803L, as entered by the provider. Search the Pennsylvania Department of State (PALS) at https://www.pals.pa.gov/. 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. 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.