Quick answers
- Which hospitals does John O. Ranker work at?
- Medicare's official clinician data lists John O. Ranker at 5 hospitals: Blanchard Valley Hospital, Memorial Hospital, Mercy St Vincent Medical Center, ProMedica Toledo Hospital and Wood County Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does John O. Ranker see patients?
- Medicare's clinician data lists 6 practice locations, including Findlay, OH, Toledo, OH and Fremont, OH. Call before your visit to confirm the address.
- What is John O. Ranker's specialty?
- Medicare lists Nephrology as the primary specialty.
- Does John O. Ranker accept Medicare assignment?
- Yes. Medicare's clinician data says John O. Ranker 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 John O. Ranker?
- (419) 874-3246, as listed in official Medicare / NPI Registry data.
- What is John O. Ranker's NPI number?
- 1508069444. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where John O. Ranker works
Medicare's Facility Affiliation Data lists John O. Ranker at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Blanchard Valley HospitalFindlay, OH · Acute Care Hospital · CCN 360095
- Memorial HospitalFremont, OH · Acute Care Hospital · CCN 360156
- Mercy St Vincent Medical CenterToledo, OH · Acute Care Hospital · CCN 360112
- ProMedica Toledo HospitalToledo, OH · Acute Care Hospital · CCN 360068
- Wood County HospitalBowling Green, OH · Acute Care Hospital · CCN 360029
Practice locations
Addresses where John O. Ranker is enrolled with Medicare (CMS data updated 2026-10-02). The first 5 of 6; the Medicare profile lists all.
- 1900 S Main StFindlay, OH 45840 (419) 874‑3246
- 4235 Secor RdToledo, OH 43623
- 605 3rd Ave, Suite BFremont, OH 43420 (419) 874‑3246
- 7007 Lighthouse WayPerrysburg, OH 43551 (419) 874‑3246
- 950 W Wooster StBowling Green, OH 43402 (419) 373‑7696
Group practices
Medicare enrollment lists John O. Ranker as a member of this group (CMS data updated 2026-10-02).
- Toledo Clinic Incorporated210 clinicians in the group
Specialties
- Nephrologyprimary
Other nephrologists in Ohio
Clinicians with the same Medicare primary specialty in Ohio — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Cincinnati College Of Medicine |
| Graduation year | 2003 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1508069444 |
| 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