Nathan Markwart, D.O.
NPI 1265774574 · Critical Care Medicine (Internal Medicine) Physician · Boca Raton, FL
Enrolled with Medicare as Practitioner - Critical Care (intensivists) · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Nathan Markwart, D.O. is a Critical Care Medicine (Internal Medicine) Physician provider in Boca Raton, FL (NPI 1265774574).
Provider details
- NPI number
- 1265774574
- Entity type
- Individual
- Primary specialty
- Critical Care Medicine (Internal Medicine) PhysicianAllopathic & Osteopathic Physicians
- Credential
- D.O.
- Sex
- Male
- Sole proprietor
- No
- License
- OS 13310 (FL)
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
13 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
608 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) |
|---|---|---|
| Critical Care, First 30-74 Minutes99291 | 538 | $216 |
| Emergent Insertion of Breathing Tube Into Windpipe Using an Endoscope31500 | 16 | $147 |
| Insertion of Non-Tunneled Central Venous Tube for Infusion (5 Years Or Older)36556 | 15 | $87 |
| Insertion of Artery Tube for Blood Sampling Or Infusion Through Skin36620 | 14 | $45 |
| Insertion of Tube Connecting Vein to Vein for Hemodialysis36800 | 13 | $124 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 12 | $119 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2013-03-25
- Last updated
- 2015-09-03
Frequently asked questions
- What is Nathan Markwart's NPI number?
- Nathan Markwart's National Provider Identifier (NPI) is 1265774574, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Nathan Markwart's specialty?
- Nathan Markwart is listed in the NPPES registry with a primary specialty of Critical Care Medicine (Internal Medicine) Physician (Allopathic & Osteopathic Physicians).
- Where is Nathan Markwart located?
- Nathan Markwart's practice location on file with NPPES is 1601 Clint Moore Rd, Boca Raton, FL 33487-2768.
- What is Nathan Markwart's phone number?
- The practice phone number listed in the NPPES registry for Nathan Markwart is (561) 939-0200.
- Does Nathan Markwart accept Medicare?
- Nathan Markwart is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Nathan Markwart's NPI active?
- Yes — Nathan Markwart's NPI (1265774574) is active in the NPPES registry as of the last update on 2015-09-03.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.