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GREGORY B MARSH
NPI 1114952009
Anesthesiology in Seattle, WA

Active since July 11, 2006PECOS EnrolledAccepts Medicare Assignment
91.13/100
CMS Quality Rating
1229 MADISON ST, SUITE 1440, SEATTLE, WA 98104(206) 625-0578(206) 625-9184 Get Directions Write a Review

NPPES record last updated: April 15, 2008. Verified against the NPPES registry weekly; last sync: November 01, 2026.

About Gregory B Marsh NPPES

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

GREGORY B MARSH (NPI 1114952009) is an individual anesthesiology provider in Seattle, Washington, licensed in Washington (MD00029703) and active in the NPI registry since July 2006. He is enrolled in Medicare PECOS and is a graduate of University Of Washington School Of Medicine (1988).

NPPES Registry Identity

NPI1114952009
Entity TypeIndividualMale
Primary Taxonomy207L00000X
Provider Legal NameGREGORY B MARSH
Location Address1229 MADISON ST, SUITE 1440Seattle, WA 98104-3586
Mailing Address1229 Madison St, Suite 1440Seattle, WA 98104-3586 · (206) 625-0578 · Fax (206) 625-9184
Phone(206) 625-0578
Fax(206) 625-9184
Sole ProprietorNo
Medical School CMSUniversity Of Washington School Of MedicineGraduated 1988
Enumeration DateJuly 11, 2006
Last NPPES UpdateApril 15, 2008
✔ NPI 1114952009 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAnesthesiologyAllopathic & Osteopathic Physicians
Taxonomy Code207L00000X
License✔ Licensed in WA · MD00029703
Definition
An anesthesiologist is trained to provide pain relief and maintenance, or restoration, of a stable condition during and immediately following an operation or an obstetric or diagnostic procedure. The anesthesiologist assesses the risk of the patient undergoing surgery and optimizes the patient's condition prior to, during and after surgery. In addition to these management responsibilities, the anesthesiologist provides medical management and consultation in pain management and critical care medicine. Anesthesiologists diagnose and treat acute, long-standing and cancer pain problems; diagnose and treat patients with critical illnesses or severe injuries; direct resuscitation in the care of patients with cardiac or respiratory emergencies, including the need for artificial ventilation; and supervise post-anesthesia recovery.
1229 MADISON ST, Seattle, WA 98104
Open in Google Maps ↗

Other Identifiers 5

Medicare PING8869808
Other105221L&i
Medicare UPINF15512
Medicaid8186322WA
OtherMA4258B/s Regence 90

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

Gregory B Marsh 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 ID3072606904
PECOS Enrollment IDI20070907000451
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 Reassignment

Medicare enrollment records show Gregory Marsh reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Physicians Anesthesia Service PLLC
0.2 mi
Anesthesiology
600 BROADWAY STE 270
Seattle, WA 98122
  • Reassigned Medicare billing, Washington enrollment
  • 233 clinicians in this Medicare group
NPI 1417962200 (206) 381-0269

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

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.

91.13/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Quality94.94
Improvement Activities40
Cost79.7

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.

SWEDISH HEALTH SERVICE
Pediatrics (Neonatal-Perinatal Medicine)
1229 MADISON ST, STE 750
SEATTLE, WA 98104
King County (206) 386-2101
JONATHAN S MARON M.D.
Anesthesiology
1229 MADISON ST, SUITE 1440
SEATTLE, WA 98104
King County (206) 625-0578
ANDREW H CHUNG M.D.
Anesthesiology
1229 MADISON ST, SUITE 1440
SEATTLE, WA 98104
King County (206) 625-0578
DENISE Y LIM M.D.
Anesthesiology
1229 MADISON ST, SUITE 1440
SEATTLE, WA 98104
King County (206) 625-0578
ROBIN E COLE MD
Obstetrics & Gynecology
1229 MADISON ST, STE 1500
SEATTLE, WA 98104
King County (206) 386-9500
SKIN SURGERY CENTER PS
Clinic/Center (Ambulatory Surgical)
1229 MADISON ST, SUITE 1480
SEATTLE, WA 98104
King County (206) 346-6647
MARK E GIBSON M.D.
Anesthesiology
1229 MADISON ST, SUITE 1440
SEATTLE, WA 98104
King County (206) 625-0578
JENNIFER L MUSHEN RN
Registered Nurse (Medical-Surgical)
1229 MADISON ST, SUITE 1600
SEATTLE, WA 98104
King County (206) 386-2600

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 Gregory Marsh's NPI number?

The NPI number for Gregory Marsh is 1114952009. It was assigned to this individual provider in the NPPES registry on July 11, 2006.

Where is Gregory Marsh located?

Gregory Marsh practices at 1229 Madison St Suite 1440, Seattle, WA 98104. The listed phone number is (206) 625-0578.

What is Gregory Marsh's specialty?

The primary specialty registered for this NPI is Anesthesiology with taxonomy code 207L00000X.

Is Gregory Marsh enrolled in Medicare?

Yes. Gregory Marsh 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 organization bills Medicare for Gregory Marsh's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gregory Marsh reassigns Medicare benefits to Physicians Anesthesia Service PLLC (Seattle, WA). The 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 Gregory Marsh'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 Gregory Marsh was last updated on April 15, 2008. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 18 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.