Sean S. To., M.D., Inc
NPI 1841809597 · Internal Medicine Physician · Chino, CA
Enrolled with Medicare as Part B Supplier - Clinic/Group Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Sean S. To., M.D., Inc is a Internal Medicine Physician organization in Chino, CA (NPI 1841809597).
Provider details
- NPI number
- 1841809597
- Entity type
- Organization
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Organization subpart
- No
- Authorized official
- Sean to, President/ Owner(951) 834-8515
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
5 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2020-07-29
- Last updated
- 2020-07-29
- Certified
- 2020-07-29
Frequently asked questions
- What is Sean S. To., M.D., Inc's NPI number?
- Sean S. To., M.D., Inc's National Provider Identifier (NPI) is 1841809597, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What type of organization is Sean S. To., M.D., Inc?
- Sean S. To., M.D., Inc is classified in the NPPES registry as Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Sean S. To., M.D., Inc located?
- Sean S. To., M.D., Inc's practice location on file with NPPES is 5562 Philadelphia St Ste 201, Chino, CA 91710.
- What is Sean S. To., M.D., Inc's phone number?
- The practice phone number listed in the NPPES registry for Sean S. To., M.D., Inc is (909) 988-1000.
- Does Sean S. To., M.D., Inc accept Medicare?
- Sean S. To., M.D., Inc is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Who is the authorized official for Sean S. To., M.D., Inc?
- The authorized official listed on Sean S. To., M.D., Inc's NPPES record is Sean to, President/ Owner. The authorized official registers and maintains the organization's NPI and is not necessarily its owner.
- Is Sean S. To., M.D., Inc's NPI active?
- Yes — Sean S. To., M.D., Inc's NPI (1841809597) is active in the NPPES registry as of the last update on 2020-07-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.