Quick answers
- Which hospitals does Nathan E. Riddell work at?
- Medicare's official clinician data lists Nathan E. Riddell at 2 hospitals: Lowell General Hospital and Tufts Medical Center. This is where the clinician works or has privileges; call the hospital to confirm.
- Where does Nathan E. Riddell see patients?
- Medicare's clinician data lists 2 practice locations, including Lowell, MA and North Chelmsford, MA. Call before your visit to confirm the address.
- What is Nathan E. Riddell's specialty?
- Medicare lists Internal Medicine as the primary specialty, and also Cardiovascular Disease (Cardiology).
- Does Nathan E. Riddell accept Medicare assignment?
- Yes. Medicare's clinician data says Nathan E. Riddell 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 Nathan E. Riddell?
- (351) 221-7080, as listed in official Medicare / NPI Registry data.
- What is Nathan E. Riddell's NPI number?
- 1245670983. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Hospitals where Nathan E. Riddell works
Medicare's Facility Affiliation Data lists Nathan E. Riddell at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.
- Lowell General HospitalLowell, MA · Acute Care Hospital · CCN 220063
- Tufts Medical CenterBoston, MA · Acute Care Hospital · CCN 220116
Practice locations
Addresses where Nathan E. Riddell is enrolled with Medicare (CMS data updated 2026-10-02).
- 1115 Westford St, Suite 2Lowell, MA 01851 (351) 221‑7080
- 14 Research Pl, Suite 3North Chelmsford, MA 01863 (978) 256‑6607
Group practices
Medicare enrollment lists Nathan E. Riddell as a member of these groups (CMS data updated 2026-10-02).
- LGH Merrimack Valley Cardiology Associates, LLC22 clinicians in the group
- TVCG Ste PLLC7 clinicians in the group
Specialties
Other internal medicine doctors in Lowell
Clinicians with the same Medicare primary specialty in Lowell, MA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2013 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1245670983 |
| 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