Mark Fitzsimmons, MD
NPI 1639284706 · Family Medicine Physician · Port Washington, WI
Enrolled with Medicare as Practitioner - Family Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mark Fitzsimmons, MD is a Family Medicine Physician provider in Port Washington, WI (NPI 1639284706).
Provider details
- NPI number
- 1639284706
- Entity type
- Individual
- Primary specialty
- Family Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 33627 (WI)
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
19 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
634 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 | 261 | $120 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 115 | $121 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 80 | $85 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 77 | $167 |
| Administration of Influenza Virus VaccineG0008 | 44 | $30 |
| Admn Sarscov2 Vacc 1 Dose90480 | 32 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 107 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 811 | 207 |
| Amlodipine Besylate | 296 | 75 |
| Lisinopril | 287 | 67 |
| Pantoprazole Sodium | 284 | 64 |
| Levothyroxine Sodium | 251 | 53 |
| Rosuvastatin Calcium | 249 | 62 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$125 across 1 record (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
- 2006-08-20
- Last updated
- 2021-11-18
- Certified
- 2021-11-18
Frequently asked questions
- What is Mark Fitzsimmons's NPI number?
- Mark Fitzsimmons's National Provider Identifier (NPI) is 1639284706, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Mark Fitzsimmons's specialty?
- Mark Fitzsimmons is listed in the NPPES registry with a primary specialty of Family Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Mark Fitzsimmons located?
- Mark Fitzsimmons's practice location on file with NPPES is 1475 W Grand Ave, Port Washington, WI 53074.
- What is Mark Fitzsimmons's phone number?
- The practice phone number listed in the NPPES registry for Mark Fitzsimmons is (262) 268-5100.
- Does Mark Fitzsimmons accept Medicare?
- Mark Fitzsimmons is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Mark Fitzsimmons's NPI active?
- Yes — Mark Fitzsimmons's NPI (1639284706) is active in the NPPES registry as of the last update on 2021-11-18.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.