Quick answers
- Which hospitals does Sean Johnson work at?
- Medicare's official clinician data lists Sean Johnson at 1 hospital: Holy Cross Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Sean Johnson see patients?
- Medicare's clinician data lists 2 practice locations, including Largo, MD and Gaithersburg, MD. Call before your visit to confirm the address.
- What is Sean Johnson's specialty?
- Medicare lists Orthopedic Surgery as the primary specialty.
- Does Sean Johnson accept Medicare assignment?
- Yes. Medicare's clinician data says Sean Johnson 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 Sean Johnson?
- (301) 618-5700, as listed in official Medicare / NPI Registry data.
- What is Sean Johnson's NPI number?
- 1164486510. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Sean Johnson works
Medicare's Facility Affiliation Data lists Sean Johnson at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Holy Cross HospitalSilver Spring, MD · Acute Care Hospital · CCN 210004
Practice locations
Addresses where Sean Johnson is enrolled with Medicare (CMS data updated 2026-10-02).
- 1221 Mercantile LnLargo, MD 20774 (301) 618‑5700
- 655 Watkins Mill RdGaithersburg, MD 20879 (240) 632‑4000
Group practices
Medicare enrollment lists Sean Johnson as a member of this group (CMS data updated 2026-10-02).
- Kaiser Foundation Health Plan of the Mid Atlantic States, Inc1,899 clinicians in the group
Specialties
- Orthopedic Surgeryprimary
Other orthopedic surgeons in Largo
Clinicians with the same Medicare primary specialty in Largo, MD — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Massachusetts Medical School |
| Graduation year | 1999 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1164486510 |
| 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