Individual provider

Rebecca O'neill, PHYSICIAN ASSISTANT

Medical Physician Assistant Surgical Physician Assistant Critical Care Medicine (Internal Medicine) Physician Medicare enrolled

Rebecca O'neill, PHYSICIAN ASSISTANT is a Medical Physician Assistant in Stamford, CT, registered under NPI 1548254774. This provider registers 3 separate taxonomy codes, which usually means they practise across more than one recognised specialty.

Getting there

The practice address on file is 1177 SUMMER ST 5TH FLOOR, Stamford, CT 06905. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

1177 SUMMER ST 5TH FLOOR, Stamford, CT 06905 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
MA063379 PA Medical Physician Assistant primary
000766 CT Surgical Physician Assistant
003558 NY Surgical Physician Assistant
MA063379 PA Critical Care Medicine (Internal…

Licences are recorded in 3 states: PA, CT, NY. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Physician Assistant
PAC ID
2961581905

Enrolled in Medicare 2 times, across 2 states:

StateEnrollment IDProvider type
New York I20170208000727 Practitioner - Physician Assistant
Pennsylvania I20220804000041 Practitioner - Physician Assistant

Medicare enrolment is recorded as approved under the provider type Practitioner - Physician Assistant. There are 2 separate enrolment records across 2 states (NY, PA). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

Licensed in 3 states

This provider holds licences in 3 states: Connecticut, New York and Pennsylvania. The practice address on file is in Stamford, CT, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

CT Connecticut practice address
Licence
000766
Specialty
Surgical Physician Assistant
Verify with the CT board →
NY New York
Licence
003558
Specialty
Surgical Physician Assistant
Verify with the NY board →
PA Pennsylvania
Licence
MA063379
Specialty
Medical Physician Assistant
Verify with the PA board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Medical covers

Definition to come... NUCC Health Care Provider Taxonomy, code 363AM0700X
Physician Assistants & Advanced Practice Nursing Providers Physician Assistant Medical

All registered taxonomy codes

This provider registers 4 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
363AM0700X Medical Physician Assistant Medical MA063379 PA primary
363AS0400X Surgical Physician Assistant Surgical 000766 CT
363AS0400X Surgical Physician Assistant Surgical 003558 NY
207RC0200X Critical Care Medicine (Internal Medicine) Physician Critical Care Medicine MA063379 PA

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1548254774 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateSep 2, 2005
Last updatedApr 3, 2026
StatusActive
Sole proprietorNo
CredentialPHYSICIAN ASSISTANT
Practice address 1177 SUMMER ST
5TH FLOOR
Stamford, CT 06905
(203) 653-4321
Mailing address 601 MEMORY LN
York, PA 17402
This record was updated on Apr 3, 2026, which is recent enough that the contact details are likely still accurate.

Number check

1548254774 passes the NPI check digit test The final digit 4 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 5 4 8 2 5 4 7 7
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 5 8 8 4 5 8 7 5

Sum = 76 · next multiple of 10 = 80 · check digit = 4 · actual last digit = 4

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1548254774?
NPI 1548254774 is the National Provider Identifier assigned to Rebecca O'neill, PHYSICIAN ASSISTANT in Stamford, CT. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Medical cover?
Definition to come...
How do I contact Rebecca O'neill, PHYSICIAN ASSISTANT?
The phone number on file with NPPES is (203) 653-4321, last updated Apr 3, 2026. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Rebecca O'neill, PHYSICIAN ASSISTANT accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1548254774 a valid number?
Yes. 1548254774 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.