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DR. PAUL JOHN CALLAHAN PSY.D.
NPI 1114062239
Psychologist - Clinical Child & Adolescent in Cambridge, MA

Active since February 20, 2007PECOS EnrolledAccepts Medicare Assignment
2557 MASSACHUSETTS AVE, CAMBRIDGE, MA 02140(781) 643-1020 Get Directions Write a Review

NPPES record last updated: July 8, 2007. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Dr. Paul John Callahan Psy.d. NPPES

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

DR. PAUL JOHN CALLAHAN PSY.D. (NPI 1114062239) is an individual clinical child & adolescent provider in Cambridge, Massachusetts, licensed in Massachusetts (6376) and active in the NPI registry since February 2007. He is enrolled in Medicare PECOS and is a graduate of Other (1991).

NPPES Registry Identity

NPI1114062239
Entity TypeIndividualMale
Primary Taxonomy103TC2200X
Provider Legal NameDR. PAUL JOHN CALLAHANCredential: PSY.D.
Location Address2557 MASSACHUSETTS AVECambridge, MA 02140-1020
Mailing Address26 Stevens TerArlington, MA 02476-7720 · (781) 643-1531
Phone(781) 643-1020
Sole ProprietorYes
Medical School CMSOtherGraduated 1991
Enumeration DateFebruary 20, 2007
Last NPPES UpdateJuly 8, 2007
✔ NPI 1114062239 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPsychologist · Clinical Child & AdolescentBehavioral Health & Social Service Providers
Taxonomy Code103TC2200X
License✔ Licensed in MA · 6376
Definition
A psychologist who develops and applies scientific knowledge to the delivery of psychological services to infants, toddlers, children and adolescents within their social context. Of particular importance to the specialty of clinical child psychology is an understanding of the basic psychological needs of children and adolescents, and how the family and other social contexts influence the socio-emotional adjustment, cognitive development, behavioral adaptation and health status of children and adolescents.
2557 MASSACHUSETTS AVE, Cambridge, MA 02140
Open in Google Maps ↗

Other Identifiers 1

OtherW05323MA · Bcbs Id #

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Harvard Pilgrim Health Care.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

Dr. Paul John Callahan Psy.d. 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.

PECOS PAC ID6103986385
PECOS Enrollment IDI20081120000901
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 Paul Callahan reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Paul Callahan Psy.D. Psychotherapy, LLC
2.3 mi
Mental Health (Including Community Mental Health Center)
26 STEVENS TER
Arlington, MA 02476
  • Reassigned Medicare billing, Massachusetts enrollment
  • Medicare enrollment name: Paul Callahan Psyd Psychotherapy LLC
NPI 1528785946 (339) 927-5545

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 11

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. JULIE S ROSS PH.D.
Psychologist
2557 MASSACHUSETTS AVE
CAMBRIDGE, MA 02140
Middlesex County (781) 643-1020
JENNIFER HEINEN RD
Dietitian, Registered
2557 MASSACHUSETTS AVE
CAMBRIDGE, MA 02140
Middlesex County (617) 744-9233
DR. MICHELE ANN DEBIASSE PHD, RDN, LDN
Dietitian, Registered
2557 MASSACHUSETTS AVE
CAMBRIDGE, MA 02140
Middlesex County (617) 744-9233
JUDITH G. GOLDBERG LICSW
Social Worker (Clinical)
2557 MASSACHUSETTS AVE
CAMBRIDGE, MA 02140
Middlesex County (617) 501-8204
MRS. KRISTIN M. HALL LMHC
Counselor (Mental Health)
2557 MASSACHUSETTS AVE
CAMBRIDGE, MA 02140
Middlesex County (860) 614-2571
KIRR ASSOCIATES INC
Counselor (Mental Health)
2557 MASSACHUSETTS AVE
CAMBRIDGE, MA 02140
Middlesex County (781) 789-0585
DR. NANCY ANN KLUG PSYD
Psychologist
2557 MASSACHUSETTS AVE
CAMBRIDGE, MA 02140
Middlesex County (617) 661-5915
LAUREN FATOVIC LICSW
Social Worker (Clinical)
2557 MASSACHUSETTS AVE
CAMBRIDGE, MA 02140
Middlesex County (617) 888-7782

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 Paul Callahan's NPI number?

The NPI number for Paul Callahan is 1114062239. It was assigned to this individual provider in the NPPES registry on February 20, 2007.

Where is Paul Callahan located?

Paul Callahan practices at 2557 Massachusetts Ave, Cambridge, MA 02140. The listed phone number is (781) 643-1020.

What is Paul Callahan's specialty?

The primary specialty registered for this NPI is Psychologist, specializing in Clinical Child & Adolescent, with taxonomy code 103TC2200X.

Is Paul Callahan enrolled in Medicare?

Yes. Paul Callahan 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 organization bills Medicare for Paul Callahan's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Paul Callahan reassigns Medicare benefits to Paul Callahan Psy.D. Psychotherapy, LLC (Arlington, 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 Paul Callahan's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Paul Callahan accept?

Health plans from Harvard Pilgrim Health Care list Paul Callahan 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 Paul Callahan was last updated on July 8, 2007. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 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.