Charles O'Brien, M.D.
NPI 1124023171 · Internal Medicine Physician · Sioux Falls, SD
Charles O'Brien, M.D. is a Internal Medicine Physician provider in Sioux Falls, SD (NPI 1124023171).
Provider details
- NPI number
- 1124023171
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 2515 (SD)
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
21 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
- 2005-06-16
- Last updated
- 2007-07-08
Frequently asked questions
- What is Charles O'Brien's NPI number?
- Charles O'Brien's National Provider Identifier (NPI) is 1124023171, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Charles O'Brien's specialty?
- Charles O'Brien is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Charles O'Brien located?
- Charles O'Brien's practice location on file with NPPES is 1305 W 18th St, Sioux Falls, SD 57105-0401.
- What is Charles O'Brien's phone number?
- The practice phone number listed in the NPPES registry for Charles O'Brien is (605) 328-2929.
- Is Charles O'Brien's NPI active?
- Yes — Charles O'Brien's NPI (1124023171) is active in the NPPES registry as of the last update on 2007-07-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.