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Mark T Callesen MD PC

Mark T Callesen MD PC is a healthcare organization registered as Psychiatric Residential Treatment Facility in Mesa, AZ, holding Type 2 (organization) NPI 1588727259 since 2006. The authorized official on file is Mark Callesen, President.

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NPI 1588727259
Entity type Organization (Type 2)
Legal business name Mark T Callesen MD PC
Practice address 1201 S ALMA SCHOOL RD, SUITE 11750, Mesa, AZ, 85210
Phone 4804644606
Fax 4804640613
Enumeration date 2006-12-17
Last updated in NPPES 2020-08-22

Authorized official

Name Mark Callesen
Title President
Phone 4804644606

Taxonomy & classification

Taxonomy code Specialty Primary License State
323P00000X Psychiatric Residential Treatment Facility Primary 23058 AZ
Copy-ready billing details
Provider: Mark T Callesen MD PC
NPI: 1588727259
Taxonomy: 323P00000X (Psychiatric Residential Treatment Facility)
Address: 1201 S ALMA SCHOOL RD, SUITE 11750, Mesa, AZ, 85210

Providers at this address

NPI Name Type Specialty Location
1457345472 Thomas Hall Individual Clinical Social Worker Mesa, AZ
1568451359 Michael Kornreich Individual Diagnostic Radiology Physician Mesa, AZ
1912996638 Penny Bowen Individual Diagnostic Radiology Physician Mesa, AZ
1477511103 Stephen Anthony Individual Clinical Psychologist Mesa, AZ
1447277264 Stateserv Homecare LLC Organization Durable Medical Equipment & Medical Supplies Mesa, AZ
1396833141 Curtis Anderson Individual Clinical Psychologist Mesa, AZ
1588821763 Holly Lawder Individual Diagnostic Radiology Physician Mesa, AZ
1932980885 James Hartwell Individual Psychiatric/Mental Health Nurse Practitioner Mesa, AZ

Verify this record

Cross-check NPI 1588727259 against the authoritative CMS record: view Mark T Callesen MD PC 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

What type of organization is Mark T Callesen MD PC?
Mark T Callesen MD PC is registered in NPPES as a Psychiatric Residential Treatment Facility (its primary provider taxonomy).
What is a Type 2 NPI?
A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.

Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2020-08-22.