MRS. GERTRUDE AREJA OSTER APRN
NPI 1265611537
Nurse Practitioner in Tucson, AZ
About Mrs. Gertrude Areja Oster Aprn NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MRS. GERTRUDE AREJA OSTER APRN (NPI 1265611537) is an individual nurse practitioner in Tucson, Arizona, licensed in Arizona (AP2816) and active in the NPI registry since November 2007. She is enrolled in Medicare PECOS and is a graduate of Other (2005).
NPPES Registry Identity
Specialties & Licenses 2
Other Names 1
Other Identifiers 2
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
Mrs. Gertrude Areja Oster Aprn 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 Reassignment
Medicare enrollment records show Gertrude Oster reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Tucson, AZ 85718
- Reassigned Medicare billing, Arizona enrollment
- 155 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 2
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.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 85718 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 2
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
TUCSON, AZ 85718
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 Gertrude Oster's NPI number?
The NPI number for Gertrude Oster is 1265611537. It was assigned to this individual provider in the NPPES registry on November 2, 2007. The provider is also known as Mrs. Trudy Areja Oster Aprn.
Where is Gertrude Oster located?
Gertrude Oster practices at 4511 N Campbell Ave Ste 100, Tucson, AZ 85718. The listed phone number is (520) 529-6500.
What is Gertrude Oster's specialty?
The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.
Is Gertrude Oster enrolled in Medicare?
Yes. Gertrude Oster 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 organization bills Medicare for Gertrude Oster's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Gertrude Oster reassigns Medicare benefits to Akdhc, LLC (Tucson, AZ). The 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 Gertrude Oster's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Gertrude Oster accept?
Health plans from Ambetter Health, Ambetter from Arizona Complete Health, Blue Cross Blue Shield of Arizona, Cigna HealthCare of Arizona, Inc and Imperial Insurance Companies, Inc. and 1 other insurer list Gertrude Oster 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.
When was this NPI record last updated?
The NPPES record for Gertrude Oster was last updated on November 22, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 years 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.
# Mrs. Gertrude Areja Oster, APRN · NPI 1265611537
Nurse Practitioner physician in Tucson, Arizona. Individual provider, active in the CMS NPPES registry since November 2, 2007.
## Identity
- **NPI:** 1265611537 (Entity type: Individual)
- **Enumerated:** November 2, 2007
- **Primary specialty:** Nurse Practitioner · taxonomy 363L00000X
- **State license:** AP2816 (Arizona)
- **Sole proprietor:** No
## Practice location
- **Address:** 4511 N CAMPBELL AVE STE 100, Tucson, AZ 85718-6424
- **Phone:** (520) 529-6500 · **Fax:** (520) 209-7337
## 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:** Akdhc, LLC (NPI 1255503017, Tucson, AZ), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2005
## Record status
- **NPPES last updated:** November 22, 2019
- **Other identifiers:** Other AP2816 (AZ); Other RN140274 (AZ)
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Source: [NPI Profile](https://npiprofile.com/npi/1265611537) · Data from the CMS NPPES public registry.