KRISTEN LYNN ZACK MD
NPI 1376105692
Internal Medicine - Nephrology in Billings, MT

Q: What is Kristen Zack's NPI number?

The NPI number for Kristen Zack is 1376105692. It was assigned to this individual provider in the NPPES registry on July 8, 2019. The provider is also known as Kristen Lynn Pietrzyk.

Q: What is Kristen Zack's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Nephrology, with taxonomy code 207RN0300X.

Q: When was this NPI record last updated?

The NPPES record for Kristen Zack was last updated on August 28, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.

Active since July 08, 2019PECOS EnrolledAccepts Medicare Assignment

1045 N 30TH ST, BILLINGS, MT 59101(406) 238-2500 Get Directions Write a Review

NPPES record last updated: August 28, 2025. Verified against the NPPES registry weekly; last sync: August 09, 2026.

On this page

About Kristen Lynn Zack Md NPPES

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

KRISTEN LYNN ZACK MD (NPI 1376105692) is an individual nephrology provider in Billings, Montana, licensed in Montana (162224) and active in the NPI registry since July 2019. She is enrolled in Medicare PECOS, is affiliated with Billings Clinic, and is a graduate of Other (2019).

NPPES Registry Identity

NPI1376105692

Entity TypeIndividualFemale

Primary Taxonomy207RN0300X

Provider Legal NameKRISTEN LYNN ZACKCredential: MD

Location Address1045 N 30TH STBillings, MT 59101-0733

Mailing Address1045 N 30th StBillings, MT 59101-0733 · (406) 238-2500

Phone(406) 238-2500

Sole ProprietorNo

Medical School CMSOtherGraduated 2019

Enumeration DateJuly 8, 2019

Last NPPES UpdateAugust 28, 2025

NPPES CertifiedAugust 28, 2025

✔ NPI 1376105692 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · NephrologyAllopathic & Osteopathic Physicians

Taxonomy Code207RN0300X

License✔ Licensed in MT · 162224

Definition

An internist who treats disorders of the kidney, high blood pressure, fluid and mineral balance and dialysis of body wastes when the kidneys do not function. This specialist consults with surgeons about kidney transplantation.

1045 N 30TH ST, Billings, MT 59101

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Other Names 1

Former Name (1)Kristen Lynn Pietrzyk

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Arizona Complete Health, Blue Cross and Blue Shield of Montana.Insurance ›

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

Kristen Lynn Zack Md 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 ID7012245475

PECOS Enrollment IDI20250912001092, I20260109001838

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.

Areas of Expertise CMS Part B claims 5

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.

76 services64 patients

New patient office or other outpatient visit with a high level of medical decision making, if using time, 60 minutes or more 99205

This is a first-time patient visit where a healthcare professional spends 60-74 minutes with you. It involves a comprehensive evaluation, including your medical history and current health condition. They'll also advise on preventive health measures and formulate a treatment plan if needed.

47 services47 patients

Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215

This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.

35 services32 patients

Urinalysis, manual test 81002

A urinalysis is a simple, non-invasive test that checks the urine for various elements such as sugar, protein, and signs of infection. It can help detect many common conditions, including kidney disease and diabetes. The manual test involves a lab technician examining a urine sample.

23 services23 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.

11 services11 patients

Hospital Affiliations CMS Care Compare 3

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

Glendive Medical Center

Critical Access Hospitals · Glendive, MT

OwnershipVoluntary non-profit - Private

CMS Certification Number271332

Location202 Prospect DrGlendive, MT 59330 · Dawson County

Emergency services

Sheridan Memorial Hospital

Acute Care Hospitals · Sheridan, WY

4/5 CMS rating

OwnershipGovernment - Local

CMS Certification Number530006

Location1401 W 5th StSheridan, WY 82801 · Sheridan County

Emergency services

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

$130.52 typical visit price

range $56.81 – $172.26

Typical copayment $32.63 (range $14.20 – $43.06)

Most-billed visit code 99204

Established Patient

$100.16 typical visit price

range $18.24 – $140.32

Typical copayment $25.04 (range $4.56 – $35.08)

Most-billed visit code 99214

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 17

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

BILLINGS CLINIC

Specialist (Research Study)