MARGARET A OPPENHEIMER MD
NPI 1598956419
Internal Medicine in Bellingham, WA
About Margaret A Oppenheimer Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MARGARET A OPPENHEIMER MD (NPI 1598956419) is an individual internal medicine provider in Bellingham, Washington, licensed in Oregon (MD151425) and active in the NPI registry since August 2007. She is enrolled in Medicare PECOS, is affiliated with Mercy Hospital South, and maintains a secondary practice location in Saint Louis.
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 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
Margaret A Oppenheimer 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
2Medicare enrollment records show Margaret Oppenheimer reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Bellingham, WA 98225
- Reassigned Medicare billing, Washington enrollment
- 107 clinicians in this Medicare group
Saint Louis, MO 63128
- Reassigned Medicare billing, Missouri enrollment
- Medicare enrollment name: St Anthonys Physician Organization Hospitalist Services Lc
- 340 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
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Mercy Hospital South
Acute Care Hospitals · Saint Louis, MOPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 98225 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 7
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
BELLINGHAM, WA 98225
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 Margaret Oppenheimer's NPI number?
The NPI number for Margaret Oppenheimer is 1598956419. It was assigned to this individual provider in the NPPES registry on August 6, 2007.
Where is Margaret Oppenheimer located?
Margaret Oppenheimer practices at 709 W Orchard Dr Suite 4, Bellingham, WA 98225. The listed phone number is (360) 318-8800.
What is Margaret Oppenheimer's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is Margaret Oppenheimer enrolled in Medicare?
Yes. Margaret Oppenheimer 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 Margaret Oppenheimer's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Margaret Oppenheimer reassigns Medicare benefits to 2 organizations: Family Care Network PLLC (Bellingham, WA) and St Anthonys Physician Organization Hospitalist Services, L.C. (Saint Louis, MO). 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 Margaret Oppenheimer's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Margaret Oppenheimer accept?
Health plans from Anthem Blue Cross and Blue Shield and Medica list Margaret Oppenheimer 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 Margaret Oppenheimer affiliated with any hospitals?
According to CMS data, Margaret Oppenheimer is affiliated with Mercy Hospital South.
When was this NPI record last updated?
The NPPES record for Margaret Oppenheimer was last updated on April 27, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.
# Margaret A Oppenheimer, MD · NPI 1598956419
Internal Medicine physician in Bellingham, Washington. Individual provider, active in the CMS NPPES registry since August 6, 2007.
## Identity
- **NPI:** 1598956419 (Entity type: Individual)
- **Enumerated:** August 6, 2007
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** MD151425 (Oregon)
- **Sole proprietor:** No
## Practice location
- **Address:** 709 W ORCHARD DR, SUITE 4, Bellingham, WA 98225-1766
- **Phone:** (360) 318-8800 · **Fax:** (360) 318-1085
## 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:** 2 organizations under Medicare reassignment (form CMS-855R): Family Care Network PLLC (NPI 1467006205, Bellingham, WA); St Anthonys Physician Organization Hospitalist Services, L.C. (NPI 1407216336, Saint Louis, MO) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Missouri, Columbia School Of Medicine, class of 2007
## Record status
- **NPPES last updated:** April 27, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1598956419) · Data from the CMS NPPES public registry.