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MARLENA OSOWSKI
NPI 1386335776
Registered Nurse in Boston, MA

Active since May 16, 2023PECOS EnrolledAccepts Medicare Assignment
850 WASHINGTON ST, BOSTON, MA 02111(617) 636-5000 Get Directions Write a Review

NPPES record last updated: May 16, 2023. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Marlena Osowski NPPES

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

MARLENA OSOWSKI (NPI 1386335776) is an individual registered nurse in Boston, Massachusetts, licensed in Massachusetts (RN2354068) and active in the NPI registry since May 2023. She is enrolled in Medicare PECOS, is affiliated with Newton-wellesley Hospital, and is a graduate of Other (2023).

NPPES Registry Identity

NPI1386335776
Entity TypeIndividualFemale
Primary Taxonomy163W00000X
Provider Legal NameMARLENA OSOWSKI
Location Address850 WASHINGTON STBoston, MA 02111-1521
Mailing Address22 Manor LnOxford, MA 01540-1502
Phone(617) 636-5000
Sole ProprietorNo
Medical School CMSOtherGraduated 2023
Enumeration DateMay 16, 2023
NPPES CertifiedMay 11, 2023
✔ NPI 1386335776 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyRegistered NurseNursing Service Providers
Taxonomy Code163W00000X
License✔ Licensed in MA · RN2354068
Definition
(1) A registered nurse is a person qualified by graduation from an accredited nursing school (depending upon schooling, a registered nurse may receive either a diploma from a hospital program, an associate degree in nursing (A.D.N.) or a Bachelor of Science degree in nursing (B.S.N.), who is licensed or certified by the state, and is practicing within the scope of that license or certification. R.N.'s assist patient in recovering and maintaining their physical or mental health. They assist physicians during treatments and examinations and administer medications. (2) A provider who is trained and educated in a formal nursing education program at an accredited school of nursing, passes a national certification examination, and is licensed by the state to practice nursing. The individual provides nursing services to patients or clients in areas such as health promotion, disease prevention, acute and chronic care and restoration and maintenance of health across the life span.
850 WASHINGTON ST, Boston, MA 02111
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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

Marlena Osowski 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 ID9830548874
PECOS Enrollment IDI20231215000656
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

2

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

Gbgastro LLC
19 mi
Gastroenterology
475 FRANKLIN ST STE 110
Framingham, MA 01702
  • Reassigned Medicare billing, Massachusetts enrollment
  • 40 clinicians in this Medicare group
NPI 1033693023 (508) 620-9200
Greater Boston Gastroenterology
19 mi
Gastroenterology
475 FRANKLIN ST, SUITE 110
Framingham, MA 01702
  • Reassigned Medicare billing, Massachusetts enrollment
  • 37 clinicians in this Medicare group
NPI 1164498796 (508) 620-9200

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 2

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.

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
22 services20 patients
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204
This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.
15 services15 patients

Hospital Affiliations CMS Care Compare 3

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

Newton-Wellesley Hospital

Acute Care Hospitals · Newton, MA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220101
Location2014 Washington StreetNewton, MA 02462 · Middlesex County
Emergency services Birthing friendly

Umass Memorial Medical Center/University Campus

Acute Care Hospitals · Worcester, MA
4/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220163
Location55 Lake Avenue NorthWorcester, MA 01655 · Worcester County
Emergency services Birthing friendly

Metrowest Medical Center

Acute Care Hospitals · Framingham, MA
2/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number220175
Location115 Lincoln StreetFramingham, MA 01701 · Middlesex County
Emergency services Birthing friendly

Other Providers at the Same Location NPPES

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

NATALIA HENNER MD
General Acute Care Hospital
850 WASHINGTON ST
BOSTON, MA 02111
Suffolk County (617) 636-5000

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 Marlena Osowski's NPI number?

The NPI number for Marlena Osowski is 1386335776. It was assigned to this individual provider in the NPPES registry on May 16, 2023.

Where is Marlena Osowski located?

Marlena Osowski practices at 850 Washington St, Boston, MA 02111. The listed phone number is (617) 636-5000.

What is Marlena Osowski's specialty?

The primary specialty registered for this NPI is Registered Nurse with taxonomy code 163W00000X.

Is Marlena Osowski enrolled in Medicare?

Yes. Marlena Osowski 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 Marlena Osowski's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Marlena Osowski reassigns Medicare benefits to 2 organizations: Gbgastro LLC (Framingham, MA) and Greater Boston Gastroenterology (Framingham, 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 Marlena Osowski's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is Marlena Osowski affiliated with any hospitals?

According to CMS data, Marlena Osowski is affiliated with Newton-Wellesley Hospital, Umass Memorial Medical Center/University Campus and Metrowest Medical Center.

When was this NPI record last updated?

The NPPES record for Marlena Osowski was last updated on May 16, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.