SONJA SCHAFFER
NPI 1336694439
Nurse Practitioner - Family in Charlton, MA
About Sonja Schaffer NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
SONJA SCHAFFER (NPI 1336694439) is an individual family provider in Charlton, Massachusetts, licensed in Massachusetts (RN2289480) and active in the NPI registry since August 2016. She is enrolled in Medicare PECOS, is affiliated with Umass Memorial Health - Harrington Hospital, and maintains 2 additional practice locations.
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Locations 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
Sonja Schaffer 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
3Medicare enrollment records show Sonja Schaffer reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Auburn, MA 01501
- Reassigned Medicare billing, Massachusetts enrollment
- 17 clinicians in this Medicare group
Oxford, MA 01540
- Reassigned Medicare billing, Massachusetts enrollment
- 2,902 clinicians in this Medicare group
Worcester, MA 01608
- Reassigned Medicare billing, Massachusetts enrollment
- 197 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 3
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 2
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Umass Memorial Health - Harrington Hospital
Acute Care Hospitals · Southbridge, MASt Vincent Hospital
Acute Care Hospitals · Worcester, MAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 01507 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 5
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
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 Sonja Schaffer's NPI number?
The NPI number for Sonja Schaffer is 1336694439. It was assigned to this individual provider in the NPPES registry on August 18, 2016.
Where is Sonja Schaffer located?
Sonja Schaffer practices at 9 Trolley Crossing Rd, Charlton, MA 01507. The listed phone number is (508) 784-1278.
What is Sonja Schaffer's specialty?
The primary specialty registered for this NPI is Nurse Practitioner, specializing in Family, with taxonomy code 363LF0000X.
Is Sonja Schaffer enrolled in Medicare?
Yes. Sonja Schaffer 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 Sonja Schaffer's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Sonja Schaffer reassigns Medicare benefits to 3 organizations: Shane Speirs MD II PLLC (Auburn, MA), Umass Memorial Medical Group, Inc. (Oxford, MA) and Saint Vincent Physician Services, Inc. (Worcester, MA). 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 Sonja Schaffer's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Sonja Schaffer accept?
Health plans from Anthem Blue Cross and Blue Shield and Taro Health list Sonja Schaffer 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 Sonja Schaffer affiliated with any hospitals?
According to CMS data, Sonja Schaffer is affiliated with Umass Memorial Health - Harrington Hospital and St Vincent Hospital.
When was this NPI record last updated?
The NPPES record for Sonja Schaffer was last updated on May 7, 2018. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 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.
# Sonja Schaffer · NPI 1336694439
Family physician in Charlton, Massachusetts. Individual provider, active in the CMS NPPES registry since August 18, 2016.
## Identity
- **NPI:** 1336694439 (Entity type: Individual)
- **Enumerated:** August 18, 2016
- **Primary specialty:** Nurse Practitioner - Family · taxonomy 363LF0000X
- **State license:** RN2289480 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 9 TROLLEY CROSSING RD, Charlton, MA 01507-1351
- **Phone:** (508) 784-1278 · **Fax:** (508) 784-1279
## 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:** 3 organizations under Medicare reassignment (form CMS-855R): Shane Speirs MD II PLLC (NPI 1699650044, Auburn, MA); Umass Memorial Medical Group, Inc. (NPI 1982381018, Oxford, MA); Saint Vincent Physician Services, Inc. (NPI 1013997329, Worcester, MA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Massachusetts Medical School, class of 2016
## Record status
- **NPPES last updated:** May 7, 2018
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Source: [NPI Profile](https://npiprofile.com/npi/1336694439) · Data from the CMS NPPES public registry.