NATHAN KLAMMER MD
NPI 1104405869
Emergency Medicine in Tulsa, OK
About Nathan Klammer Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
NATHAN KLAMMER MD (NPI 1104405869) is an individual emergency medicine provider in Tulsa, Oklahoma, licensed in Oklahoma (42931) and active in the NPI registry since April 2021. He is enrolled in Medicare PECOS, is affiliated with Hillcrest Hospital Pryor, and is a graduate of University Of Arkansas College Of Medicine (2021).
NPPES Registry Identity
Specialties & Licenses
Group Practice 1
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare and accepts Medicare assignment
Nathan Klammer Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.
Medicare Billing Reassignments
4Medicare enrollment records show Nathan Klammer reassigns Medicare billing to 4 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Tulsa, OK 74104
- Reassigned Medicare billing, Oklahoma enrollment
- 162 clinicians in this Medicare group
Muskogee, OK 74401
- Reassigned Medicare billing, Texas enrollment
- 655 clinicians in this Medicare group
Newport, AR 72112
- Reassigned Medicare billing, Arkansas enrollment
- 65 clinicians in this Medicare group
Monticello, AR 71655
- Reassigned Medicare billing, Arkansas enrollment
- 126 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Areas of Expertise CMS Part B claims 4
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Hospital Affiliations CMS Care Compare 5
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Hillcrest Hospital Pryor
Acute Care Hospitals · Pryor, OKHillcrest Hospital Claremore
Acute Care Hospitals · Claremore, OKHillcrest Hospital South
Acute Care Hospitals · Tulsa, OKBailey Medical Center, LLC
Acute Care Hospitals · Owasso, OKEastern Oklahoma Medical Center
Critical Access Hospitals · Poteau, OKPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 74104 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES 12
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
TULSA, OK 74104
TULSA, OK 74104
Frequently Asked Questions NPPES & CMS
Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.
What is Nathan Klammer's NPI number?
The NPI number for Nathan Klammer is 1104405869. It was assigned to this individual provider in the NPPES registry on April 7, 2021.
Where is Nathan Klammer located?
Nathan Klammer practices at 1145 S Utica Ave Ste 365, Tulsa, OK 74104. The listed phone number is (918) 728-3354.
What is Nathan Klammer's specialty?
The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.
Is Nathan Klammer enrolled in Medicare?
Yes. Nathan Klammer is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.
Which organizations bill Medicare for Nathan Klammer's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Nathan Klammer reassigns Medicare benefits to 4 organizations: Green Country Emergency Physicians Group Of Tulsa PLLC (Tulsa, OK), Creek Nation Hospital & Clinics (Muskogee, OK), Unity Health - Newport (Newport, AR) and Monticello Ess LLC (Monticello, AR). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Nathan Klammer's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Nathan Klammer accept?
Health plans from Arkansas Blue Cross and Blue Shield, Health Advantage and Octave list Nathan Klammer as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.
Is Nathan Klammer affiliated with any hospitals?
According to CMS data, Nathan Klammer is affiliated with Hillcrest Hospital Pryor, Hillcrest Hospital Claremore, Hillcrest Hospital South, Bailey Medical Center, LLC and Eastern Oklahoma Medical Center.
When was this NPI record last updated?
The NPPES record for Nathan Klammer was last updated on April 9, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.
# Nathan Klammer, MD · NPI 1104405869
Emergency Medicine physician in Tulsa, Oklahoma. Individual provider, active in the CMS NPPES registry since April 7, 2021.
## Identity
- **NPI:** 1104405869 (Entity type: Individual)
- **Enumerated:** April 7, 2021
- **Primary specialty:** Emergency Medicine · taxonomy 207P00000X
- **State license:** 42931 (Oklahoma)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 1145 S UTICA AVE STE 365, Tulsa, OK 74104-4004
- **Phone:** (918) 728-3354
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 4 organizations under Medicare reassignment (form CMS-855R): Green Country Emergency Physicians Group Of Tulsa PLLC (NPI 1972698553, Tulsa, OK); Creek Nation Hospital & Clinics (NPI 1922873611, Muskogee, OK); Unity Health - Newport (NPI 1164152815, Newport, AR); Monticello Ess LLC (NPI 1184010753, Monticello, AR) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Arkansas College Of Medicine, class of 2021
## Record status
- **NPPES last updated:** April 9, 2025
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Source: [NPI Profile](https://npiprofile.com/npi/1104405869) · Data from the CMS NPPES public registry.