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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

JUSTIN WILLIAM HALLORAN MD
NPI 1386384535
Psychiatry & Neurology - Psychiatry in Cambridge, MA

Active since March 29, 2022PECOS Enrolled
1493 CAMBRIDGE ST, CAMBRIDGE, MA 02139(617) 665-1000 Get Directions Write a Review

NPPES record last updated: September 3, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Justin William Halloran Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

JUSTIN WILLIAM HALLORAN MD (NPI 1386384535) is an individual psychiatry provider in Cambridge, Massachusetts, licensed in Massachusetts (1023355) and active in the NPI registry since March 2022. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1386384535
Entity TypeIndividualMale
Primary Taxonomy2084P0800X
Provider Legal NameJUSTIN WILLIAM HALLORANCredential: MD
Location Address1493 CAMBRIDGE STCambridge, MA 02139-1047
Mailing Address1493 Cambridge StCambridge, MA 02139-1047 · (617) 665-1000
Phone(617) 665-1000
Sole ProprietorNo
Enumeration DateMarch 29, 2022
Last NPPES UpdateSeptember 3, 2026
NPPES CertifiedSeptember 3, 2026
✔ NPI 1386384535 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPsychiatry & Neurology · PsychiatryAllopathic & Osteopathic Physicians
Taxonomy Code2084P0800X
License✔ Licensed in MA · 1023355
Definition
A Psychiatrist specializes in the prevention, diagnosis, and treatment of mental disorders, emotional disorders, psychotic disorders, mood disorders, anxiety disorders, substance-related disorders, sexual and gender identity disorders and adjustment disorders. Biologic, psychological, and social components of illnesses are explored and understood in treatment of the whole person. Tools used may include diagnostic laboratory tests, prescribed medications, evaluation and treatment of psychological and interpersonal problems with individuals and families, and intervention for coping with stress, crises, and other problems.
1493 CAMBRIDGE ST, Cambridge, MA 02139
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Justin William Halloran Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Justin Halloran reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Cambridge Public Health Commission
Same address
General Acute Care Hospital
1493 CAMBRIDGE ST
Cambridge, MA 02139
  • Reassigned Medicare billing, Massachusetts enrollment
  • 362 clinicians in this Medicare group
NPI 1487603585 (617) 665-1000

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 02139 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$189.86 typical visit price
range $63.72 – $189.86
Typical copayment $47.46 (range $15.93 – $47.46)
Most-billed visit code 99205
Established Patient
$78.84 typical visit price
range $21.07 – $155.29
Typical copayment $19.71 (range $5.26 – $38.82)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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.

ELIZABETH BLACK-SUCHY CCC-SLP
Speech-Language Pathologist
1493 CAMBRIDGE ST
CAMBRIDGE, MA 02139
Middlesex County (617) 591-6767
ZACHARY OLIFF DO
Emergency Medicine
1493 CAMBRIDGE ST
CAMBRIDGE, MA 02139
Middlesex County (617) 665-1000
JACOB DYLAN WOLFE LICSW
Social Worker (Clinical)
1493 CAMBRIDGE ST
CAMBRIDGE, MA 02139
Middlesex County (617) 665-1646
SARAH-JO SANTILLI RN
Registered Nurse
1493 CAMBRIDGE ST
CAMBRIDGE, MA 02139
Middlesex County (617) 272-6455
JULIE LYNNE MERCER
Registered Nurse
1493 CAMBRIDGE ST
CAMBRIDGE, MA 02139
Middlesex County (617) 591-4212
TAIANA KATSARAS LICSW
Social Worker (Clinical)
1493 CAMBRIDGE ST
CAMBRIDGE, MA 02139
Middlesex County (617) 665-1185
ANGELA DE SILVA
Registered Nurse (Ambulatory Care)
1493 CAMBRIDGE ST
CAMBRIDGE, MA 02139
Middlesex County (617) 665-1000
RORY HAUSER
Registered Nurse (Neonatal, Low-Risk)
1493 CAMBRIDGE ST
CAMBRIDGE, MA 02139
Middlesex County (802) 595-9868

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 Justin Halloran's NPI number?

The NPI number for Justin Halloran is 1386384535. It was assigned to this individual provider in the NPPES registry on March 29, 2022.

Where is Justin Halloran located?

Justin Halloran practices at 1493 Cambridge St, Cambridge, MA 02139. The listed phone number is (617) 665-1000.

What is Justin Halloran's specialty?

The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Psychiatry, with taxonomy code 2084P0800X.

Is Justin Halloran enrolled in Medicare?

Yes. Justin Halloran is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Justin Halloran's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Justin Halloran reassigns Medicare benefits to Cambridge Public Health Commission (Cambridge, MA). 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 Justin Halloran'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 Justin Halloran was last updated on September 3, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 53 days 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.