PETER G MASLAK MD
NPI 1265403067
Internal Medicine - Hematology in Buffalo, NY
About Peter G Maslak Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
PETER G MASLAK MD (NPI 1265403067) is an individual hematology provider in Buffalo, New York, licensed in New York (169520) and active in the NPI registry since January 2006. He is enrolled in Medicare PECOS and is a graduate of Icahn School Of Medicine At Mount Sinai (1984).
NPPES Registry Identity
Specialties & Licenses
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
Peter G Maslak 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 Peter Maslak reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Buffalo, NY 14263
- Reassigned Medicare billing, New York enrollment
- 602 clinicians in this Medicare group
New York, NY 10065
- Reassigned Medicare billing, New York enrollment
- 428 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
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 14263 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.
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.
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 Peter Maslak's NPI number?
The NPI number for Peter Maslak is 1265403067. It was assigned to this individual provider in the NPPES registry on January 30, 2006.
Where is Peter Maslak located?
Peter Maslak practices at Elm And Carlton St, Buffalo, NY 14263. The listed phone number is (716) 845-2300.
What is Peter Maslak's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology, with taxonomy code 207RH0000X.
Is Peter Maslak enrolled in Medicare?
Yes. Peter Maslak 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 Peter Maslak's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Peter Maslak reassigns Medicare benefits to 2 organizations: Roswell Park Cancer Institute (Buffalo, NY) and Memorial Hematology Lymphoma Group (New York, NY). 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 Peter Maslak'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 Peter Maslak was last updated on January 5, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.
# Peter G Maslak, MD · NPI 1265403067
Hematology physician in Buffalo, New York. Individual provider, active in the CMS NPPES registry since January 30, 2006.
## Identity
- **NPI:** 1265403067 (Entity type: Individual)
- **Enumerated:** January 30, 2006
- **Primary specialty:** Internal Medicine - Hematology · taxonomy 207RH0000X
- **State license:** 169520 (New York)
- **Sole proprietor:** No
## Practice location
- **Address:** ELM AND CARLTON ST, Buffalo, NY 14263-0001
- **Phone:** (716) 845-2300
## 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): Roswell Park Cancer Institute (NPI 1720036593, Buffalo, NY); Memorial Hematology Lymphoma Group (NPI 1891766366, New York, NY) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Icahn School Of Medicine At Mount Sinai, class of 1984
## Record status
- **NPPES last updated:** January 5, 2023
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Source: [NPI Profile](https://npiprofile.com/npi/1265403067) · Data from the CMS NPPES public registry.