DR. MARGARET L. ISAAC (M.D.) – Internal Medicine Physician, NPI 1255363727

DR. MARGARET L. ISAAC (M.D.) is a healthcare provider. based in Seattle, Washington. specializing in INTERNAL MEDICINE, HOSPICE/PALLIATIVE CARE. They hold the professional credentials M.D.. They hold a License No. MD00048241 (WA). The NPI Number for DR. MARGARET L. ISAAC (M.D.) is 1255363727

Main info

Female
23 Years Of Experience
Accepts Medicare Assignment
Name
DR. MARGARET L. ISAAC (M.D.)
NPI
1255363727
Phone
Not provided
Address
PO BOX 50095
Enumeration Date
7 July 2006
Last Update Date
1 June 2018

Doctor Profile

Medical School Name
UNIVERSITY OF WASHINGTON SCHOOL OF MEDICINE
Secondary Phone
2065984333
Graduation Year
2003 (23 years ago)
PAC ID
6901809177
Group Practice PAC ID
0446162697
Professional Enrollment ID
I20070907000365
Address ID
WA981950001SE1959XSTXX400
Telehealth
Yes
Data current as of
19 May 2026

Profile Insights

NPPES metrics only — not quality of care.

Methodology
Experience57
Completeness75
Years active:19State licenses:1Digital endpointsOther names

4,056 INTERNAL MEDICINE in WA

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Provider Addresses for DR. MARGARET L. ISAAC (M.D.)

  • PO BOX 50095

    SEATTLE, WA 981455095

    Phone:

    Type: Mailing

  • Harborview Medical Center, 325, 9th Avenue, Little Saigon, First Hill, Seattle, King County, Washington, 98104, United States

    SEATTLE, WA 98104

    Phone: (206) 744-5865

    Type: Location

NPPES updates history

No NPPES updates recorded for this provider.

Prescription Activity

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Open Payments (CMS)

CMS reports 1 Open Payments records for all available years, with a total value of $19.

Total Amount is formed as General ($19) + Research ($0) + Ownership ($0) = $19.

Last reported payment date: 2024-11-20 • Largest payer in this snapshot: Sumitomo Pharma America, Inc. ($19).

Total Amount

$19

General + Research + Ownership

Payments

1

Total payment records

General Amount

$19

General payments

Research Amount

$0

Research funding

Ownership Amount

$0

Ownership interests

Ownership Count

0

Ownership records

Last Payment Date

2024-11-20

Latest reported date

Top Companies

Largest payers in this snapshot

View all Open Payments →|Open Payments Risk Radar →

Medicare Enrollment & Revalidation

Source: CMS public data · Not endorsed by CMS ·

Educational use only—not medical, billing, or legal advice.

PECOS enrollment status

Participating (accepts Medicare assignment)

Enrollment effective: 2007-09-07

PECOS data refreshed: 2026-05-27

Medicare revalidation (CMS due date list)

Due date not assigned yet

CMS is tracking this Medicare enrollment for revalidation, but has not published a due date.

Enrollment records

1

Earliest due date

Not assigned (TBD)

CMS data updated

2026-06-01

Revalidation progress

  1. Medicare enrolled
  2. On CMS revalidation list
  3. Due date assigned
  4. Revalidate in PECOS

CMS enrollment records

Enrollment IDTypeSpecialtyStateDue date
I20070907000365IInternal MedicineWATBD

What to do next

  • No action required while the due date shows TBD.
  • Check the CMS Revalidation Lookup Tool periodically — CMS updates the list about every 60 days.
  • Do not submit a revalidation application in PECOS until CMS publishes a concrete due date.

Verify on CMS Revalidation Lookup Tool

Prepare CMS-855 application → · Look up this NPI in PECOS → · Verify on CMS PECOS

Medicare Utilization (FFS)

Source: CMS public data · Not endorsed by CMS · Beneficiary counts under 11 are suppressed in source data ·

Educational use only—not medical, billing, or legal advice.

Top Medicare procedures (2023) · refreshed 2026-05-27

HCPCSDescriptionServicesBeneficiariesMedicare allowed
99214Established patient office or other outpatient visit, 30-39 minutes6937$0
99213Established patient office or other outpatient visit, 20-29 minutes6050$0
99232Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes3913$0
View full utilization report →

Insurance plans in this area (ZIP 98145)

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Group practice members

Group practice members are other physicians who share the same Group Practice PAC ID with this doctor. When doctors form a group practice and register in PECOS as a single entity, they receive a shared identification number. This table lists all providers in the same group practice.
PAC ID: 0446162697View full group profile

Reviews

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Frequently asked questions

Where can patients find DR. MARGARET L. ISAAC (M.D.)'s NPI?
You can confirm DR. MARGARET L. ISAAC (M.D.) with NPI 1255363727; it appears in the national provider directory.
Is DR. MARGARET L. ISAAC (M.D.) currently active in the NPI registry?
CMS-published data lists DR. MARGARET L. ISAAC (M.D.) as an active registrant.
Can you summarize DR. MARGARET L. ISAAC (M.D.)'s specialty in plain language?
Clinically, the directory lists DR. MARGARET L. ISAAC (M.D.) with Internal Medicine Physician. Clinical services aligned with this taxonomy classification.
What location shows for DR. MARGARET L. ISAAC (M.D.)?
We surface Seattle, Washington for DR. MARGARET L. ISAAC (M.D.) based on available NPPES addresses.
Is DR. MARGARET L. ISAAC (M.D.) a real provider?
This page reflects official NPPES data for NPI 1255363727. Always confirm identity and privileges with the practice and licensing boards.

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