CALLIE O'BRIEN NP
NPI 1407400393
Nurse Practitioner in Boston, MA

Q: What is Callie O'brien's NPI number?

The NPI number for Callie O'brien is 1407400393. It was assigned to this individual provider in the NPPES registry on July 29, 2019.

Q: What is Callie O'brien's specialty?

The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.

Q: When was this NPI record last updated?

The NPPES record for Callie O'brien was last updated on July 15, 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.

Active since July 29, 2019PECOS EnrolledAccepts Medicare Assignment

86.28/100

CMS Quality Rating

75 FRANCIS ST, BOSTON, MA 02115(617) 732-5500 Get Directions Write a Review

NPPES record last updated: July 15, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Jul 15, 2026, Oct 8, 2019, Jul 29, 2019 (3 updates tracked since 2019).

On this page

About Callie O'brien Np NPPES

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

CALLIE O'BRIEN NP (NPI 1407400393) is an individual nurse practitioner in Boston, Massachusetts, licensed in Massachusetts (RN2294535) and active in the NPI registry since July 2019. She is enrolled in Medicare PECOS, is affiliated with Brigham And Women's Hospital, and maintains a secondary practice location in Boston.

NPPES Registry Identity

NPI1407400393

Entity TypeIndividualFemale

Primary Taxonomy363L00000X

Provider Legal NameCALLIE O'BRIENCredential: NP

Location Address75 FRANCIS STBoston, MA 02115-6106

Mailing Address75 Francis StBoston, MA 02115-6106 · (617) 732-5500

Phone(617) 732-5500

Sole ProprietorNo

Medical School CMSOtherGraduated 2019

Enumeration DateJuly 29, 2019

Last NPPES UpdateJuly 15, 20263 updates tracked since enumeration

NPPES CertifiedJuly 15, 2026

✔ NPI 1407400393 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers

Taxonomy Code363L00000X

License✔ Licensed in MA · RN2294535

Definition

(1) A registered nurse provider with a graduate degree in nursing prepared for advanced practice involving independent and interdependent decision making and direct accountability for clinical judgment across the health care continuum or in a certified specialty. (2) A registered nurse who has completed additional training beyond basic nursing education and who provides primary health care services in accordance with state nurse practice laws or statutes. Tasks performed by nurse practitioners vary with practice requirements mandated by geographic, political, economic, and social factors. Nurse practitioner specialists include, but are not limited to, family nurse practitioners, gerontological nurse practitioners, pediatric nurse practitioners, obstetric-gynecologic nurse practitioners, and school nurse practitioners.

75 FRANCIS ST, Boston, MA 02115

Open in Google Maps ↗

Secondary Practice Location 1

Location 1450 Brookline AveBoston, MA 02215-5418 · Phone (617) 632-3000

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Taro Health.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

Callie O'brien Np 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 ID3870926777

PECOS Enrollment IDI20191206002387

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 Reassignments

Medicare enrollment records show Callie O'brien reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Brigham & Womens Physicians Organization Inc

0.1 mi

Internal Medicine

75 FRANCIS ST
Boston, MA 02115

Reassigned Medicare billing, Massachusetts enrollment
4,574 clinicians in this Medicare group

NPI 1033535497 (617) 732-5500

Dana-Farber Cancer Institute, Inc.

0.1 mi

Special Hospital

75 FRANCIS ST
Boston, MA 02115

Reassigned Medicare billing, Massachusetts enrollment
531 clinicians in this Medicare group

NPI 1346433257 (617) 635-6904

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 4

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.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232

Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.

143 services62 patients

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233

Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.

72 services38 patients

Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222

Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.

52 services47 patients

Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223

Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.

22 services22 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Brigham And Women's Hospital

Acute Care Hospitals · Boston, MA

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number220110

Location75 Francis StreetBoston, MA 02115 · Suffolk County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 02115 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

$97.64 typical visit price

range $63.72 – $189.86

Typical copayment $24.41 (range $15.93 – $47.46)

Most-billed visit code 99203

Established Patient

$111.18 typical visit price

range $21.07 – $155.29

Typical copayment $27.79 (range $5.26 – $38.82)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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.

86.28/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored as part of a group practice

Quality

69.36

Promoting Interoperability

100

Improvement Activities

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.

RUMA RAJBHANDARI

Internal Medicine (Gastroenterology)

75 FRANCIS ST
BOSTON, MA 02115

Suffolk County (617) 525-6841

WENYA LINDA BI

Neurological Surgery

75 FRANCIS ST
BOSTON, MA 02115

Suffolk County (203) 645-9485

CHI YUEN CHAN M.D.

Student in an Organized Health Care Education/Training Program

75 FRANCIS ST
BOSTON, MA 02115

Suffolk County (617) 732-5500

JENNIFER MICHELLE THOMAS MD

Radiology (Diagnostic Radiology)

75 FRANCIS ST, DEPARTMENT OF RADIOLOGY
BOSTON, MA 02115

Suffolk County (617) 732-6248

GAURAV SHARMA M.D.

Surgery (Vascular Surgery)

75 FRANCIS ST, BRIGHAM AND WOMEN'S HOSPITAL
BOSTON, MA 02115

Suffolk County (951) 259-0890

YEU-SHIN CINDY CHANG M.D., M.P.H.

Emergency Medicine

75 FRANCIS ST, BWH DEPT. OF EMERGENCY MEDICINE
BOSTON, MA 02115

Suffolk County (617) 732-8070

CARA L RICHARDS

Physician Assistant

75 FRANCIS ST
BOSTON, MA 02115

Suffolk County (617) 732-5500

LARA COAKLEY

Nurse Practitioner (Family)

75 FRANCIS ST
BOSTON, MA 02115

Suffolk County (617) 732-5500

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 Callie O'brien's NPI number?

The NPI number for Callie O'brien is 1407400393. It was assigned to this individual provider in the NPPES registry on July 29, 2019.

Where is Callie O'brien located?

Callie O'brien practices at 75 Francis St, Boston, MA 02115. The listed phone number is (617) 732-5500.

What is Callie O'brien's specialty?

The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.

Is Callie O'brien enrolled in Medicare?

Yes. Callie O'brien 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 Callie O'brien's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Callie O'brien reassigns Medicare benefits to 2 organizations: Brigham & Womens Physicians Organization Inc (Boston, MA) and Dana-Farber Cancer Institute, Inc. (Boston, 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 Callie O'brien's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Callie O'brien accept?

Health plans from Taro Health list Callie O'brien 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.

Is Callie O'brien affiliated with any hospitals?

According to CMS data, Callie O'brien is affiliated with Brigham And Women's Hospital.

When was this NPI record last updated?

The NPPES record for Callie O'brien was last updated on July 15, 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.