Quick answers
- Which hospitals does Jay Grassell work at?
- Medicare's official clinician data lists Jay Grassell at 1 hospital: Adventist Health and Rideout. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Jay Grassell see patients?
- Medicare's clinician data lists 2 practice locations, including Hanford, CA and Marysville, CA. Call before your visit to confirm the address.
- What is Jay Grassell's specialty?
- Medicare lists Hospitalist as the primary specialty, and also Family Practice.
- Does Jay Grassell accept Medicare assignment?
- Yes. Medicare's clinician data says Jay Grassell 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 Jay Grassell?
- (559) 537-0550, as listed in official Medicare / NPI Registry data.
- What is Jay Grassell's NPI number?
- 1821029687. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Jay Grassell works
Medicare's Facility Affiliation Data lists Jay Grassell at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Adventist Health and RideoutMarysville, CA · Acute Care Hospital · CCN 050133
Practice locations
Addresses where Jay Grassell is enrolled with Medicare (CMS data updated 2026-10-02).
- 115 Mall DrHanford, CA 93230 (559) 537‑0550
- 726 4th StMarysville, CA 95901 (530) 749‑4300
Group practices
Medicare enrollment lists Jay Grassell as a member of this group (CMS data updated 2026-10-02).
- Galen Inpatient Physicians PC1,077 clinicians in the group
Specialties
- Hospitalistprimary
- Family Practicealso
Other hospitalists in Hanford
Clinicians with the same Medicare primary specialty in Hanford, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Medical College Of Wisconsin |
| Graduation year | 1981 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1821029687 |
| 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