ALLISON GREGG
NPI 1386343911
Clinical Neuropsychologist in Belmont, MA
About Allison Gregg NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
ALLISON GREGG (NPI 1386343911) is an individual clinical neuropsychologist in Belmont, Massachusetts, licensed in Massachusetts (PSY10001181) and active in the NPI registry since March 2023. She is enrolled in Medicare PECOS and is a graduate of Other (2023).
NPPES Registry Identity
Specialties & Licenses
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
Allison Gregg 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 Allison Gregg reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Belmont, MA 02478
- Reassigned Medicare billing, Massachusetts enrollment
- 422 clinicians in this Medicare group
Newton, MA 02462
- Reassigned Medicare billing, Massachusetts enrollment
- 992 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.
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.
BELMONT, MA 02478
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 Allison Gregg's NPI number?
The NPI number for Allison Gregg is 1386343911. It was assigned to this individual provider in the NPPES registry on March 2, 2023.
Where is Allison Gregg located?
Allison Gregg practices at 115 Mill St, Belmont, MA 02478. The listed phone number is (617) 855-2000.
What is Allison Gregg's specialty?
The primary specialty registered for this NPI is Clinical Neuropsychologist with taxonomy code 103G00000X.
Is Allison Gregg enrolled in Medicare?
Yes. Allison Gregg 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 Allison Gregg's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Allison Gregg reassigns Medicare benefits to 2 organizations: The Mclean Hospital Corporation (Belmont, MA) and Mass General Brigham Medical Group Suburban Massachusetts Inc (Newton, 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 Allison Gregg's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Allison Gregg accept?
Health plans from Anthem Blue Cross and Blue Shield and Harvard Pilgrim Health Care list Allison Gregg 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 Allison Gregg was last updated on April 7, 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.
# Allison Gregg · NPI 1386343911
Clinical Neuropsychologist provider in Belmont, Massachusetts. Individual provider, active in the CMS NPPES registry since March 2, 2023.
## Identity
- **NPI:** 1386343911 (Entity type: Individual)
- **Enumerated:** March 2, 2023
- **Primary specialty:** Clinical Neuropsychologist · taxonomy 103G00000X
- **State license:** PSY10001181 (Massachusetts)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 115 MILL ST, Belmont, MA 02478-1048
- **Phone:** (617) 855-2000
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): The Mclean Hospital Corporation (NPI 1114979580, Belmont, MA); Mass General Brigham Medical Group Suburban Massachusetts Inc (NPI 1538191218, Newton, MA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2023
## Record status
- **NPPES last updated:** April 7, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1386343911) · Data from the CMS NPPES public registry.