Michael Hemmersmeier, D.O.
NPI 1366404832 · Family Medicine Physician · O Fallon, MO
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Michael Hemmersmeier, D.O. is a Family Medicine Physician provider in O Fallon, MO (NPI 1366404832).
Provider details
- NPI number
- 1366404832
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- D.O.
- Sex
- Male
- Sole proprietor
- No
- License
- 108737 (MO)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
1,408 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
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 .
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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 753 | $93 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 249 | $16 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 234 | $124 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 41 | $63 |
| X-Ray of Chest, 2 Views71046 | 35 | $10 |
| Annual Wellness Visit; Includes a Personalized Prevention Plan of Service (pps), Initial Visit |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 198 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 1,348 | 425 |
| Levothyroxine Sodium | 1,302 | 362 |
| Amlodipine Besylate | 1,118 | 338 |
| Rosuvastatin Calcium | 881 | 285 |
| Lisinopril | 783 | 248 |
| Omeprazole | 713 | 214 |
| Alprazolam |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$57 across 2 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-04-03
- Last updated
- 2020-10-22
- Certified
- 2020-10-22
Frequently asked questions
- What is Michael Hemmersmeier's NPI number?
- Michael Hemmersmeier's National Provider Identifier (NPI) is 1366404832, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Michael Hemmersmeier's specialty?
- Michael Hemmersmeier is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Michael Hemmersmeier located?
- Michael Hemmersmeier's practice location on file with NPPES is 1101 Highway K, O Fallon, MO 63366-8431.
- What is Michael Hemmersmeier's phone number?
- The practice phone number listed in the NPPES registry for Michael Hemmersmeier is (636) 379-4590.
- Does Michael Hemmersmeier accept Medicare?
- Michael Hemmersmeier is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Michael Hemmersmeier's NPI active?
- Yes — Michael Hemmersmeier's NPI (1366404832) is active in the NPPES registry as of the last update on 2020-10-22.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.