Quick answers
- Does John W. Mercer Jr. accept Medicare assignment?
- Yes. Medicare's clinician data says John W. Mercer Jr. accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- What is John W. Mercer Jr.'s NPI number?
- 1205988540. 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 W. Mercer Jr. works
Medicare's Facility Affiliation Data lists John W. Mercer Jr. at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Minden Medical CenterMinden, LA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 190144
Practice locations
Addresses where John W. Mercer Jr. is enrolled with Medicare (CMS data updated October 2, 2026).
- 3025 W Cherry LnMeridian, ID 83642
- 427 Homer RdMinden, LA 71055 (318) 377‑8855
- 431 Homer RdMinden, LA 71055 (318) 377‑8855
- 4424 E Flamingo AveNampa, ID 83687
Group practices
Medicare enrollment lists John W. Mercer Jr. as a member of these groups (CMS data updated October 2, 2026).
- Saint Alphonsus Regional Medical Center Inc680 clinicians in the group
- Minden Physician Practices LLC44 clinicians in the group
Specialties
- Obstetrics/Gynecologyprimary
Other OB-GYNs in Meridian
Clinicians with the same Medicare primary specialty in Meridian, ID — not a recommendation.
Other clinicians in Saint Alphonsus Regional Medical Center Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1997 (29 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1205988540 |
| 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 October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- 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