FREDERICK DIETZ MD
NPI 1235249426
Internal Medicine - Rheumatology in Rockford, IL
About Frederick Dietz Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
FREDERICK DIETZ MD (NPI 1235249426) is an individual rheumatology provider in Rockford, Illinois, licensed in Illinois (036-050026) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 3
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Frederick Dietz Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignment
Medicare enrollment records show Frederick Dietz reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Rockford, IL 61103
- Reassigned Medicare billing, Illinois enrollment
- 1,375 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.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 61103 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 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
ROCKFORD, IL 61103
ROCKFORD, IL 61103
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 Frederick Dietz's NPI number?
The NPI number for Frederick Dietz is 1235249426. It was assigned to this individual provider in the NPPES registry on August 30, 2006.
Where is Frederick Dietz located?
Frederick Dietz practices at 2300 N Rockton Ave, Rockford, IL 61103. The listed phone number is (815) 971-2000.
What is Frederick Dietz's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Rheumatology, with taxonomy code 207RR0500X.
Is Frederick Dietz enrolled in Medicare?
Yes. Frederick Dietz is registered in the Medicare PECOS enrollment system.
Which organization bills Medicare for Frederick Dietz's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Frederick Dietz reassigns Medicare benefits to Rockford Health Physicians (Rockford, IL). 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 Frederick Dietz's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Frederick Dietz was last updated on February 2, 2010. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.
# Frederick Dietz, MD · NPI 1235249426
Rheumatology physician in Rockford, Illinois. Individual provider, active in the CMS NPPES registry since August 30, 2006.
## Identity
- **NPI:** 1235249426 (Entity type: Individual)
- **Enumerated:** August 30, 2006
- **Primary specialty:** Internal Medicine - Rheumatology · taxonomy 207RR0500X
- **State license:** 036-050026 (Illinois)
- **Sole proprietor:** No
## Practice location
- **Address:** 2300 N ROCKTON AVE, Rockford, IL 61103-3619
- **Phone:** (815) 971-2000
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** Rockford Health Physicians (NPI 1023275278, Rockford, IL), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** February 2, 2010
- **Other identifiers:** Medicare UPIN C37275 (IL); Medicare PIN 207880 (IL); Medicaid 036050026 (IL)
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Source: [NPI Profile](https://npiprofile.com/npi/1235249426) · Data from the CMS NPPES public registry.