DR. BRIAN P O'CONNOR II M.D., MPH
NPI 1487087615
Internal Medicine in Walnut Creek, CA

Q: What is Brian O'connor's NPI number?

The NPI number for Brian O'connor is 1487087615. It was assigned to this individual provider in the NPPES registry on August 12, 2013.

Q: What is Brian O'connor's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Q: When was this NPI record last updated?

The NPPES record for Brian O'connor was last updated on September 7, 2016. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.

Active since August 12, 2013PECOS EnrolledAccepts Medicare Assignment

85.73/100

CMS Quality Rating

1220 ROSSMOOR PARKWAY, WALNUT CREEK, CA 94595(925) 947-3312(925) 947-3396 Get Directions Write a Review

NPPES record last updated: September 7, 2016. Verified against the NPPES registry weekly; last sync: October 25, 2026.

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About Dr. Brian P O'connor Ii M.d., Mph NPPES

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

DR. BRIAN P O'CONNOR II M.D., MPH (NPI 1487087615) is an individual internal medicine provider in Walnut Creek, California, licensed in California (A131848) and active in the NPI registry since August 2013. He is enrolled in Medicare PECOS and is a graduate of Other (2012).

NPPES Registry Identity

NPI1487087615

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameDR. BRIAN P O'CONNOR IICredential: M.D., MPH

Location Address1220 ROSSMOOR PARKWAYWalnut Creek, CA 94595-2501

Mailing Address1450 Treat Blvd, Ste 300Walnut Creek, CA 94597-2168

Phone(925) 947-3312

Fax(925) 947-3396

Sole ProprietorNo

Medical School CMSOtherGraduated 2012

Enumeration DateAugust 12, 2013

Last NPPES UpdateSeptember 7, 2016

✔ NPI 1487087615 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in CA · A131848

Definition

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

1220 ROSSMOOR PARKWAY, Walnut Creek, CA 94595

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Other Identifiers 1

Medicaid390200000XCA

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. Brian P O'connor Ii M.d., Mph 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 ID42528226

PECOS Enrollment IDI20151008000532

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 Brian O'connor reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

John Muir Trauma Physicians Billing Service

2.9 mi

Hospitalist

1601 YGNACIO VALLEY RD
Walnut Creek, CA 94598

Reassigned Medicare billing, California enrollment
810 clinicians in this Medicare group

NPI 1093864837 (925) 947-5331

John Muir Physician Network

3.5 mi

General Practice

1450 TREAT BLVD, SUITE 300
Walnut Creek, CA 94597

Reassigned Medicare billing, California enrollment
650 clinicians in this Medicare group

NPI 1841407665 (925) 296-9872

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 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.

446 services192 patients

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.

180 services118 patients

Hospital discharge day management, more than 30 minutes 99239

Hospital discharge day management over 30 minutes involves a detailed process to ensure a smooth transition from hospital to home. It includes final examinations, discussion of your hospital stay, post-discharge instructions, and coordinating follow-up care.

143 services142 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.

59 services59 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94595 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

$153.83 typical visit price

range $69.00 – $202.35

Typical copayment $38.45 (range $17.25 – $50.58)

Most-billed visit code 99204

Established Patient

$119.48 typical visit price

range $23.44 – $166.46

Typical copayment $29.87 (range $5.86 – $41.61)

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.

85.73/100

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

Scored as part of a group practice

Quality

82.68

Promoting Interoperability

Improvement Activities

Cost

70.58

Referred Medical Equipment & Supplies CMS DME claims

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Home ventilator, any type, used with non-invasive interface, (e.g., mask, chest shell) E0466

DME-Other DME · category DE005N

1 supplier12 claims12 services$768.64 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 7

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

DR. UYEN-CHI N HUYNH M.D.

Internal Medicine

1220 ROSSMOOR PARKWAY
WALNUT CREEK, CA 94595

Contra Costa County (925) 947-3312

DR. ZAINAB D MEZBAN MD

Internal Medicine

1220 ROSSMOOR PARKWAY
WALNUT CREEK, CA 94595

Contra Costa County (925) 947-3312

RUNJHUN MISRA D.O.

Internal Medicine

1220 ROSSMOOR PARKWAY
WALNUT CREEK, CA 94595

Contra Costa County (925) 947-3312

DR. KARTIK RAMA KRISHNAN M.D.

Internal Medicine

1220 ROSSMOOR PARKWAY
WALNUT CREEK, CA 94595

Contra Costa County (925) 947-3312

DR. NASON AZIZI M.D.

Internal Medicine

1220 ROSSMOOR PARKWAY
WALNUT CREEK, CA 94595

Contra Costa County (925) 947-3312

DAVID LEWIS PFEIFER

Dentist

1220 ROSSMOOR PARKWAY, # 1
WALNUT CREEK, CA 94595

Contra Costa County (925) 935-5800

RAJESH K JOSHI M.D.

Internal Medicine

1220 ROSSMOOR PARKWAY
WALNUT CREEK, CA 94595

Contra Costa County (925) 947-3312

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 Brian O'connor's NPI number?

The NPI number for Brian O'connor is 1487087615. It was assigned to this individual provider in the NPPES registry on August 12, 2013.

Where is Brian O'connor located?

Brian O'connor practices at 1220 Rossmoor Parkway, Walnut Creek, CA 94595. The listed phone number is (925) 947-3312.

What is Brian O'connor's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Brian O'connor enrolled in Medicare?

Yes. Brian O'connor 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 Brian O'connor's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Brian O'connor reassigns Medicare benefits to 2 organizations: John Muir Trauma Physicians Billing Service (Walnut Creek, CA) and John Muir Physician Network (Walnut Creek, CA). 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 Brian O'connor'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 Brian O'connor was last updated on September 7, 2016. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.