Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

MATTHEW WILLIAM STIER M.D.
NPI 1902244791
Internal Medicine in Lake Barrington, IL

Q: What is Matthew Stier's NPI number?

The NPI number for Matthew Stier is 1902244791. It was assigned to this individual provider in the NPPES registry on June 13, 2013.

Q: What is Matthew Stier's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Q: When was this NPI record last updated?

The NPPES record for Matthew Stier was last updated on October 19, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 days 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 June 13, 2013PECOS Enrolled

95.01/100

CMS Quality Rating

22285 N PEPPER RD STE 311, LAKE BARRINGTON, IL 60010(847) 382-4410 Get Directions Write a Review

NPPES record last updated: October 19, 2026. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Aug 1, 2019, Jun 27, 2016 (2 updates tracked since 2016).

On this page

About Matthew William Stier M.d. NPPES

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

MATTHEW WILLIAM STIER M.D. (NPI 1902244791) is an individual internal medicine provider in Lake Barrington, Illinois, licensed in Illinois (125062675) and active in the NPI registry since June 2013. He is enrolled in Medicare PECOS, is affiliated with Osf Saint Elizabeth Mdl Ctr, and is a graduate of University Of Illinois College Of Med (chi/peor/rock/chm-urb) (2013).

NPPES Registry Identity

NPI1902244791

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameMATTHEW WILLIAM STIERCredential: M.D.

Location Address22285 N PEPPER RD STE 311Lake Barrington, IL 60010-2541

Mailing Address22285 N Pepper Rd Ste 311Lake Barrington, IL 60010-2541 · (847) 382-4410

Phone(847) 382-4410

Sole ProprietorNo

Medical School CMSUniversity Of Illinois College Of Med (chi/peor/rock/chm-urb)Graduated 2013

Enumeration DateJune 13, 2013

Last NPPES UpdateOctober 19, 20262 updates tracked since enumeration

NPPES CertifiedOctober 19, 2026

✔ NPI 1902244791 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in IL · 125062675

Definition

A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.

Also ListedInternal Medicine · GastroenterologyTaxonomy 207RG0100X · License 036139723 (IL)

22285 N PEPPER RD STE 311, Lake Barrington, IL 60010

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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter Health, Ambetter Health of Delaware, Quartz.Insurance ›

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

Matthew William Stier M.d. 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 ID1850524760

PECOS Enrollment IDI20190814003074

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

Medicare enrollment records show Matthew Stier reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Gi Partners Of Illinois, PLLC

12 mi

Gastroenterology

1880 W WINCHESTER RD, #201
Libertyville, IL 60048

Reassigned Medicare billing, Illinois enrollment
74 clinicians in this Medicare group

NPI 1548613995 (847) 247-0187

Rockford Gastroenterology Associates, Ltd.

43 mi

Specialist

401 ROXBURY RD
Rockford, IL 61107

Reassigned Medicare billing, Illinois enrollment
33 clinicians in this Medicare group

NPI 1447207741 (815) 397-7340

Osf Multi-Specialty Group

123 mi

Internal Medicine

8600 N STATE ROUTE 91
Peoria, IL 61615

Reassigned Medicare billing, Illinois enrollment
2,944 clinicians in this Medicare group

NPI 1154908929 (309) 683-5050

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 14

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.

Injection, vedolizumab, intravenous, 1 mg J3380

Vedolizumab is a medication given via injection. It's used to treat certain bowel conditions (such as Crohn's disease, ulcerative colitis) by reducing inflammation. It works by blocking a certain protein that causes this inflammation.

5,100 services13 patients

Pathology examination of tissue using a microscope, intermediate complexity 88305

A pathology examination of tissue with intermediate complexity involves studying a small sample of your body tissue under a microscope. This helps in identifying any abnormal cells or signs of disease. It's a detailed process requiring expert analysis to ensure accurate results.

297 services124 patients

Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito G0500

Moderate sedation is a method where a physician uses medication to help you relax during a gastrointestinal endoscopy. An independent trained observer will be present to monitor your vital signs and ensure your safety throughout the procedure. It's a common and safe practice.

180 services175 patients

Removal of polyps or growths of large bowel using an endoscope with mechanical snare 45385

This procedure involves using a thin, flexible tube called an endoscope to examine the large bowel. If any abnormal growths or polyps are found, a tool called a mechanical snare is used to remove them. This is a common method to prevent potential health issues.

96 services96 patients

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.

91 services77 patients

Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43239

This procedure involves using a thin, flexible tube with a light and camera, known as an endoscope, to examine the esophagus, stomach, and upper part of the small intestine. Small tissue samples are taken for further examination to help diagnose various conditions.

85 services84 patients

Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222

Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.

65 services65 patients

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232

Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.

50 services34 patients

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

30 services28 patients

Biopsy of large bowel using a flexible endoscope 45380

A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.

18 services18 patients

Administration of chemotherapy into vein, 1 hour or less 96413

Chemotherapy is a treatment that uses drugs to destroy cancer cells. When administered into a vein, it's often through an IV. This procedure usually lasts 1 hour or less. You may feel a slight pinch as the needle is inserted, but it's generally painless.

17 services15 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

Diagnostic exam of large bowel using a flexible endoscope 45378

This procedure, known as a colonoscopy, involves using a flexible tube with a light and camera to examine the large intestine. It helps detect any abnormalities such as polyps or inflammation. It's a standard procedure to ensure gut health.

14 services14 patients

Infusion into a vein for therapy, prevention, or diagnosis, 1 hour or less 96365

This is a procedure where a medical professional inserts a small tube into your vein to deliver medication, nutrients, or fluids directly into your bloodstream. This can be for treatment, prevention, or diagnosis. The process typically takes less than an hour.

14 services14 patients

Hospital Affiliations CMS Care Compare 5

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

Osf Saint Elizabeth Mdl Ctr

Acute Care Hospitals · Ottawa, IL

3/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140110

Location1100 E Norris DriveOttawa, IL 61350 · La Salle County

Emergency services Birthing friendly

Uw Health

Acute Care Hospitals · Rockford, IL

3/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140228

Location1401 East State StreetRockford, IL 61104 · Winnebago County

Emergency services Birthing friendly

Saint Anthony Medical Center

Acute Care Hospitals · Rockford, IL

2/5 CMS rating

OwnershipVoluntary non-profit - Church

CMS Certification Number140233

Location5666 East State StreetRockford, IL 61108 · Winnebago County

Emergency services Birthing friendly

Osf Saint Paul Medical Center

Critical Access Hospitals · Mendota, IL

OwnershipVoluntary non-profit - Church

CMS Certification Number141310

Location1401 E 12th StreetMendota, IL 61342 · La Salle County

Emergency services

Rochelle Community Hospital

Critical Access Hospitals · Rochelle, IL

OwnershipVoluntary non-profit - Private

CMS Certification Number141312

Location900 N 2nd StRochelle, IL 61068 · Ogle County

Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60010 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

$137.43 typical visit price

range $59.81 – $181.38

Typical copayment $34.35 (range $14.95 – $45.34)

Most-billed visit code 99204

Established Patient

$105.07 typical visit price

range $19.15 – $147.12

Typical copayment $26.26 (range $4.78 – $36.78)

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.

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.

95.01/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored through an Alternative Payment Model

Quality

80.02

Promoting Interoperability

100

Improvement Activities

Other Providers at the Same Location NPPES 3

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

ERIN E MICKLINGHOFF CNP

Nurse Practitioner (Adult Health)

22285 N PEPPER RD STE 311
LAKE BARRINGTON, IL 60010

Cook County (847) 382-4410

NICOLE M GENTILE MD

Internal Medicine (Gastroenterology)

22285 N PEPPER RD STE 311
LAKE BARRINGTON, IL 60010

Cook County (847) 382-4410

NISTHA RAWAL DO

Internal Medicine (Gastroenterology)

22285 N PEPPER RD STE 311
LAKE BARRINGTON, IL 60010

Cook County (847) 382-4410

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 Matthew Stier's NPI number?

The NPI number for Matthew Stier is 1902244791. It was assigned to this individual provider in the NPPES registry on June 13, 2013.

Where is Matthew Stier located?

Matthew Stier practices at 22285 N Pepper Rd Ste 311, Lake Barrington, IL 60010. The listed phone number is (847) 382-4410.

What is Matthew Stier's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Matthew Stier enrolled in Medicare?

Yes. Matthew Stier 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 Matthew Stier's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Matthew Stier reassigns Medicare benefits to 3 organizations: Gi Partners Of Illinois, PLLC (Libertyville, IL), Rockford Gastroenterology Associates, Ltd. (Rockford, IL) and Osf Multi-Specialty Group (Peoria, IL). 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 Matthew Stier's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Matthew Stier accept?

Health plans from Ambetter Health, Ambetter Health of Delaware and Quartz list Matthew Stier as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Matthew Stier affiliated with any hospitals?

According to CMS data, Matthew Stier is affiliated with Osf Saint Elizabeth Mdl Ctr, Uw Health, Saint Anthony Medical Center, Osf Saint Paul Medical Center and Rochelle Community Hospital.

When was this NPI record last updated?

The NPPES record for Matthew Stier was last updated on October 19, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 days 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.