Quick answers
- Which hospitals does Joaquin Castillo Marroquin work at?
- Medicare's official clinician data lists Joaquin Castillo Marroquin at 2 hospitals: Corona Regional Medical Center and Kaiser Foundation Hospital, Riverside. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Joaquin Castillo Marroquin see patients?
- Medicare's clinician data lists 2 practice locations, including Riverside, CA and Corona, CA. Call before your visit to confirm the address.
- What is Joaquin Castillo Marroquin's specialty?
- Medicare lists Emergency Medicine as the primary specialty.
- Does Joaquin Castillo Marroquin accept Medicare assignment?
- Yes. Medicare's clinician data says Joaquin Castillo Marroquin 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 Joaquin Castillo Marroquin?
- (951) 353-2000, as listed in official Medicare / NPI Registry data.
- What is Joaquin Castillo Marroquin's NPI number?
- 1316407323. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Joaquin Castillo Marroquin works
Medicare's Facility Affiliation Data lists Joaquin Castillo Marroquin at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Corona Regional Medical CenterCorona, CA · Acute Care Hospital · CCN 050329
- Kaiser Foundation Hospital, RiversideRiverside, CA · Acute Care Hospital · CCN 050686
Practice locations
Addresses where Joaquin Castillo Marroquin is enrolled with Medicare (CMS data updated 2026-10-02).
- 10800 Magnolia AveRiverside, CA 92505 (951) 353‑2000
- 800 S Main StCorona, CA 92882 (951) 737‑4343
Group practices
Medicare enrollment lists Joaquin Castillo Marroquin as a member of these groups (CMS data updated 2026-10-02).
- Southern California Permanente Medical Group11,293 clinicians in the group
- Corona Regional Emergency Medical Associates Inc6 clinicians in the group
Specialties
- Emergency Medicineprimary
Other emergency medicine doctors in Riverside
Clinicians with the same Medicare primary specialty in Riverside, CA — not a recommendation.
Clinician information
| Credential | DO |
|---|---|
| Medical school | University Of North Texas Hsc, College Of Osteopathic Med |
| Graduation year | 2019 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1316407323 |
| 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