GREGORY J STREFF DO
NPI 1558314005
Internal Medicine - Pulmonary Disease in Grand Blanc, MI
About Gregory J Streff Do NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
GREGORY J STREFF DO (NPI 1558314005) is an individual pulmonary disease provider in Grand Blanc, Michigan, licensed in Michigan (5101008684) and active in the NPI registry since May 2006. He is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 4
Accepted Insurance
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Gregory J Streff Do is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
2Medicare enrollment records show Gregory Streff reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Grand Blanc, MI 48439
- Reassigned Medicare billing, Michigan enrollment
- 4 clinicians in this Medicare group
Flushing, MI 48433
- Reassigned Medicare billing, Michigan enrollment
- 328 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 12
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 48439 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Medicare Quality Performance CMS QPP · MIPS
Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.
Referred Medical Equipment & Supplies CMS DME claims 33
Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.
Other Providers at the Same Location NPPES 6
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
GRAND BLANC, MI 48439
GRAND BLANC, MI 48439
GRAND BLANC, MI 48439
GRAND BLANC, MI 48439
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 Gregory Streff's NPI number?
The NPI number for Gregory Streff is 1558314005. It was assigned to this individual provider in the NPPES registry on May 18, 2006.
Where is Gregory Streff located?
Gregory Streff practices at 9450 S Saginaw Rd Suite E, Grand Blanc, MI 48439. The listed phone number is (810) 695-4000.
What is Gregory Streff's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Pulmonary Disease, with taxonomy code 207RP1001X.
Is Gregory Streff enrolled in Medicare?
Yes. Gregory Streff is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Gregory Streff's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Gregory Streff reassigns Medicare benefits to 2 organizations: Michigan Lung And Critical Care Specialists, PC (Grand Blanc, MI) and Memorial Hospital (Flushing, MI). 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 Gregory Streff's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Gregory Streff accept?
Health plans from Ambetter Health, Ambetter from Buckeye Health Plan, Ambetter from Meridian and Priority Health list Gregory Streff 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 Gregory Streff was last updated on July 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.