Nancy Niemann Royer, MD
NPI 1326094145 · Emergency Medicine Physician · O Fallon, MO
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Nancy Niemann Royer, MD is a Emergency Medicine Physician provider in O Fallon, MO (NPI 1326094145).
Provider details
- NPI number
- 1326094145
- Entity type
- Individual
- Primary specialty
- Emergency Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- R9E46 (MO)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
20 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
81 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. 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.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Emergency Department Visit With High Level of Medical Decision Making99285 | 52 | $169 |
| Emergency Department Visit With Moderate Level of Medical Decision Making99284 | 29 | $117 |
Typical Medicare-allowed amounts for these services range $117–$169 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-05-25
- Last updated
- 2021-12-17
- Certified
- 2021-12-17
Frequently asked questions
- What is Nancy Niemann Royer's NPI number?
- Nancy Niemann Royer's National Provider Identifier (NPI) is 1326094145, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Nancy Niemann Royer's specialty?
- Nancy Niemann Royer is listed in the NPPES registry with a primary specialty of Emergency Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Nancy Niemann Royer located?
- Nancy Niemann Royer's practice location on file with NPPES is 2 Progress Point Parkway, O Fallon, MO 63368.
- What is Nancy Niemann Royer's phone number?
- The practice phone number listed in the NPPES registry for Nancy Niemann Royer is (636) 344-1151.
- Does Nancy Niemann Royer accept Medicare?
- Nancy Niemann Royer is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Nancy Niemann Royer's NPI active?
- Yes — Nancy Niemann Royer's NPI (1326094145) is active in the NPPES registry as of the last update on 2021-12-17.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.