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John M Willis, DO

John M Willis is a Internal Medicine Physician provider (Internal Medicine) practicing in Mansfield, TX, registered in the NPPES registry with NPI 1205891207 since 2006. The credential DO stands for Doctor of Osteopathic Medicine.

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NPI 1205891207
Entity type Individual (Type 1)
Name John M Willis
Credential DO
Sex Male
Practice address 252 MATLOCK RD STE 130, Mansfield, TX, 76063
Phone 6822428990
Fax 6822428996
Enumeration date 2006-04-20
Last updated in NPPES 2022-03-23

Taxonomy & licenses

Taxonomy code Specialty Primary License State
207R00000X Internal Medicine Physician Primary J0366 TX

DO — Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO credential

Other identifiers

Identifier Type State Issuer
129827510 Medicaid TX
8X9688 Other TX BLUE CROSS
Copy-ready billing details
Provider: John Willis, DO
NPI: 1205891207
Taxonomy: 207R00000X (Internal Medicine Physician)
Address: 252 MATLOCK RD STE 130, Mansfield, TX, 76063

Other providers at this practice address

NPI Name Type Specialty Location
1750769840 Khoi Tran Individual Family Medicine Physician Mansfield, TX
1386140168 Susanna Avanesyan Individual Internal Medicine Physician Mansfield, TX
1538709084 Monica Phillips Individual Family Nurse Practitioner Mansfield, TX

Verify this record

Cross-check NPI 1205891207 against the authoritative CMS record: view John M Willis on the official NPPES registry .

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. Read the full guide or validate an NPI number.

Frequently asked questions

Where does John Willis practice?
The practice location on file with NPPES is in Mansfield, TX. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for John Willis?
The National Provider Identifier (NPI) for John Willis is 1205891207, a Type 1 (individual) record in the CMS NPPES registry.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2022-03-23.