Quick answers
- Which hospitals does Michael J. Callahan work at?
- Medicare's official clinician data lists Michael J. Callahan at 5 hospitals: Ascension St Vincent Anderson, Ascension St Vincent Hospital, Ascension St Vincent Kokomo, Hendricks Regional Health and Reid Health. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Michael J. Callahan see patients?
- Medicare's clinician data lists 3 practice locations, including Indianapolis, IN. Call before your visit to confirm the address.
- What is Michael J. Callahan's specialty?
- Medicare lists Gynecological Oncology as the primary specialty, and also Obstetrics/Gynecology.
- Does Michael J. Callahan accept Medicare assignment?
- Yes. Medicare's clinician data says Michael J. Callahan accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
- What is the phone number for Michael J. Callahan?
- (317) 338-2345, as listed in official Medicare / NPI Registry data.
- What is Michael J. Callahan's NPI number?
- 1548396492. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Michael J. Callahan works
Medicare's Facility Affiliation Data lists Michael J. Callahan at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Ascension St Vincent AndersonAnderson, IN · Acute Care Hospital · CCN 150088
- Ascension St Vincent HospitalIndianapolis, IN · Acute Care Hospital · CCN 150084
- Ascension St Vincent KokomoKokomo, IN · Acute Care Hospital · CCN 150010
- Hendricks Regional HealthDanville, IN · Acute Care Hospital · CCN 150005
- Reid HealthRichmond, IN · Acute Care Hospital · CCN 150048
Practice locations
Addresses where Michael J. Callahan is enrolled with Medicare (CMS data updated 2026-10-02).
- 2001 W 86th StIndianapolis, IN 46260 (317) 338‑2345
- 8240 Naab Rd, Suite 155Indianapolis, IN 46260 (317) 338‑7760
- 8402 Harcourt RdIndianapolis, IN 46260 (317) 338‑4372
Group practices
Medicare enrollment lists Michael J. Callahan as a member of this group (CMS data updated 2026-10-02).
- St Vincent Physician Services Hospital and Health Care Center275 clinicians in the group
Specialties
- Gynecological Oncologyprimary
- Obstetrics/Gynecologyalso
Other gynecologic oncologists in Indianapolis
Clinicians with the same Medicare primary specialty in Indianapolis, IN — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Indiana University School Of Medicine |
| Graduation year | 1999 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1548396492 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
- National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians