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MARIN UNDERHILL
NPI 1114897527
Physician Assistant in Billings, MT

Active since November 10, 2025PECOS EnrolledAccepts Medicare Assignment
801 N 29TH ST, BILLINGS, MT 59101(406) 238-2500 Get Directions Write a Review

NPPES record last updated: November 10, 2025. Verified against the NPPES registry weekly; last sync: August 09, 2026.

About Marin Underhill NPPES

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

MARIN UNDERHILL (NPI 1114897527) is an individual physician assistant in Billings, Montana and active in the NPI registry since November 2025. She is enrolled in Medicare PECOS, is affiliated with Billings Clinic, and is a graduate of Other (2025).

NPPES Registry Identity

NPI1114897527
Entity TypeIndividualFemale
Primary Taxonomy363A00000X
Provider Legal NameMARIN UNDERHILL
Location Address801 N 29TH STBillings, MT 59101-0905
Mailing Address801 N 29th StBillings, MT 59101-0905
Phone(406) 238-2500
Sole ProprietorNo
Medical School CMSOtherGraduated 2025
Enumeration DateNovember 10, 2025
NPPES CertifiedNovember 10, 2025
✔ NPI 1114897527 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPhysician AssistantPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363A00000X
Definition
A physician assistant is a person who has successfully completed an accredited education program for physician assistant, is licensed by the state and is practicing within the scope of that license. Physician assistants are formally trained to perform many of the routine, time-consuming tasks a physician can do. In some states, they may prescribe medications. They take medical histories, perform physical exams, order lab tests and x-rays, and give inoculations. Most states require that they work under the supervision of a physician.
801 N 29TH ST, Billings, MT 59101
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Marin Underhill 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 ID9335625912
PECOS Enrollment IDI20260114000388
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.

Hospital Affiliations CMS Care Compare

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

Billings Clinic

Acute Care Hospitals · Billings, MT
4/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number270004
Location2800 10th Ave NBillings, MT 59101 · Yellowstone County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 59101 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
$87.97 typical visit price
range $56.81 – $172.26
Typical copayment $21.99 (range $14.20 – $43.06)
Most-billed visit code 99203
Established Patient
$70.82 typical visit price
range $18.24 – $140.32
Typical copayment $17.70 (range $4.56 – $35.08)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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.

AMANDA NEWBERN LANGVE PT
Physical Therapist
801 N 29TH ST
BILLINGS, MT 59101
Yellowstone County (406) 238-2500
KIRK KENFIELD PA
Physician Assistant (Surgical)
801 N 29TH ST
BILLINGS, MT 59101
Yellowstone County (406) 238-2500
ELIZABETH V CONNOR MD
Obstetrics & Gynecology (Gynecologic Oncology)
801 N 29TH ST
BILLINGS, MT 59101
Yellowstone County (406) 238-5000
ALEXANDER RAMSEY PA-C
Physician Assistant
801 N 29TH ST
BILLINGS, MT 59101
Yellowstone County (406) 238-2500
BILLINGS CLINIC
Occupational Therapist
801 N 29TH ST
BILLINGS, MT 59101
Yellowstone County (406) 238-2500
JERALD A. BELL MD
Ophthalmology
801 N 29TH ST
BILLINGS, MT 59101
Yellowstone County (406) 238-2501
MELANIE SCHMITZ PA-C
Physician Assistant (Surgical)
801 N 29TH ST
BILLINGS, MT 59101
Yellowstone County (406) 238-2500
AARON JAMES AUDET M.D.
Family Medicine
801 N 29TH ST
BILLINGS, MT 59101
Yellowstone County (406) 238-2500

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 Marin Underhill's NPI number?

The NPI number for Marin Underhill is 1114897527. It was assigned to this individual provider in the NPPES registry on November 10, 2025.

Where is Marin Underhill located?

Marin Underhill practices at 801 N 29th St, Billings, MT 59101. The listed phone number is (406) 238-2500.

What is Marin Underhill's specialty?

The primary specialty registered for this NPI is Physician Assistant with taxonomy code 363A00000X.

Is Marin Underhill enrolled in Medicare?

Yes. Marin Underhill 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.

Is Marin Underhill affiliated with any hospitals?

According to CMS data, Marin Underhill is affiliated with Billings Clinic.

When was this NPI record last updated?

The NPPES record for Marin Underhill was last updated on November 10, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 months 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.