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DENNIS S O'BRIEN PAC
NPI 1407895956
Physician Assistant - Medical in Springfield, MA

Active since June 06, 2006PECOS EnrolledAccepts Medicare Assignment
3300 MAIN ST, 3RD FLOOR, STE C&D, SPRINGFIELD, MA 01199(413) 794-7033(413) 794-7297 Get Directions Write a Review

NPPES record last updated: December 16, 2019. Verified against the NPPES registry weekly; last sync: July 26, 2026.

About Dennis S O'brien Pac NPPES

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

DENNIS S O'BRIEN PAC (NPI 1407895956) is an individual medical provider in Springfield, Massachusetts, licensed in Massachusetts (PA4779) and active in the NPI registry since June 2006. He is enrolled in Medicare PECOS, is affiliated with Baystate Medical Center, and is a graduate of Other (2004).

NPPES Registry Identity

NPI1407895956
Entity TypeIndividualMale
Primary Taxonomy363AM0700X
Provider Legal NameDENNIS S O'BRIENCredential: PAC
Location Address3300 MAIN ST, 3RD FLOOR, STE C&DSpringfield, MA 01199-1619
Mailing Address280 Chestnut St, 2nd FloorSpringfield, MA 01199-1619 · (413) 794-5700
Phone(413) 794-7033
Fax(413) 794-7297
Sole ProprietorNo
Medical School CMSOtherGraduated 2004
Enumeration DateJune 6, 2006
Last NPPES UpdateDecember 16, 2019
✔ NPI 1407895956 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPhysician Assistant · MedicalPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363AM0700X
License✔ Licensed in MA · PA4779
3300 MAIN ST, Springfield, MA 01199
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Anthem Blue Cross and Blue Shield, Providence Health Plan.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dennis S O'brien Pac 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 ID3274598388
PECOS Enrollment IDI20140131000250
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.

Areas of Expertise CMS Part B claims 5

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.
111 services89 patients
Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 99231
Follow-up hospital inpatient care is a daily service where a healthcare professional checks on your health progress during your hospital stay. Each session typically lasts 15 minutes, involving updates on your condition and adjustments to your treatment plan, if necessary.
83 services73 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.
43 services34 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.
32 services32 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.

Baystate Medical Center

Acute Care Hospitals · Springfield, MA
1/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220077
Location759 Chestnut StreetSpringfield, MA 01199 · Hampden County
Emergency services Birthing friendly

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.

LINDA THERIAULT PA-C
Physician Assistant (Medical)
3300 MAIN ST, 2ND FLOOR SUITE A
SPRINGFIELD, MA 01199
Hampden County (413) 794-7246
ALAN SEIGEL CLINICAL SOCIAL WORK
Social Worker (Clinical)
3300 MAIN ST, ADULT BEHAVIORAL HEALTHY BAYSTATE MEDICAL CENTER
SPRINGFIELD, MA 01199
Hampden County (413) 794-7035
LAURA A DOVE MD
Psychiatry & Neurology (Psychiatry)
3300 MAIN ST
SPRINGFIELD, MA 01199
Hampden County (413) 794-7284
GORDON GARRISON LICSW
Social Worker (Clinical)
3300 MAIN ST
SPRINGFIELD, MA 01199
Hampden County (413) 794-7035
NANCY A ALLEN NP
Nurse Practitioner (Adult Health)
3300 MAIN ST, 3RD FLOOR SUITE A
SPRINGFIELD, MA 01199
Hampden County (413) 794-7031
MARYANN O'MELIA HAYES LDN
Nutritionist
3300 MAIN ST, 3RD FLOOR DIABETES EDUC AND SELF MGMT PROGRAM
SPRINGFIELD, MA 01199
Hampden County (413) 794-7194
OCTAVIAN REMUS ADAM M.D.
Psychiatry & Neurology (Neurology)
3300 MAIN ST, 3RD FLOOR, SUITE C&D
SPRINGFIELD, MA 01199
Hampden County (413) 794-7033
CYNTHIA J JOHNSON NP
Nurse Practitioner (Family)
3300 MAIN ST, 4TH FLOOR SUITE C
SPRINGFIELD, MA 01199
Hampden County (413) 794-0813

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 Dennis O'brien's NPI number?

The NPI number for Dennis O'brien is 1407895956. It was assigned to this individual provider in the NPPES registry on June 6, 2006.

Where is Dennis O'brien located?

Dennis O'brien practices at 3300 Main St 3rd Floor, Ste C&d, Springfield, MA 01199. The listed phone number is (413) 794-7033.

What is Dennis O'brien's specialty?

The primary specialty registered for this NPI is Physician Assistant, specializing in Medical, with taxonomy code 363AM0700X.

Is Dennis O'brien enrolled in Medicare?

Yes. Dennis 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.

What insurance does Dennis O'brien accept?

Health plans from Anthem Blue Cross and Blue Shield and Providence Health Plan list Dennis 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 Dennis O'brien affiliated with any hospitals?

According to CMS data, Dennis O'brien is affiliated with Baystate Medical Center.

When was this NPI record last updated?

The NPPES record for Dennis O'brien was last updated on December 16, 2019. NPI Profile syncs with the weekly NPPES data releases published by CMS.