JOHN FOX MAST MD
NPI 1811488646
Family Medicine in Aurora, IL

Q: What is John Mast's NPI number?

The NPI number for John Mast is 1811488646. It was assigned to this individual provider in the NPPES registry on May 29, 2018.

Q: What is John Mast's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Q: When was this NPI record last updated?

The NPPES record for John Mast was last updated on September 25, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 12 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 May 29, 2018PECOS EnrolledAccepts Medicare Assignment

2000 OGDEN AVE, AURORA, IL 60504(866) 565-8607(312) 563-8661 Get Directions Write a Review

NPPES record last updated: September 25, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

On this page

About John Fox Mast Md NPPES

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

JOHN FOX MAST MD (NPI 1811488646) is an individual family medicine provider in Aurora, Illinois, licensed in Illinois (036156608) and active in the NPI registry since May 2018. He is enrolled in Medicare PECOS, is affiliated with Copley Memorial Hospital, and maintains a secondary practice location in Aurora.

NPPES Registry Identity

NPI1811488646

Entity TypeIndividualMale

Primary Taxonomy207Q00000X

Provider Legal NameJOHN FOX MASTCredential: MD

Location Address2000 OGDEN AVEAurora, IL 60504-5893

Mailing Address2000 Ogden Ave Ste P050Aurora, IL 60504-5893 · (630) 499-2404 · Fax (630) 499-4750

Phone(866) 565-8607

Fax(312) 563-8661

Sole ProprietorNo

Medical School CMSLoyola University Of Chicago, Stritch School Of MedicineGraduated 2018

Enumeration DateMay 29, 2018

Last NPPES UpdateSeptember 25, 2025

NPPES CertifiedSeptember 25, 2025

✔ NPI 1811488646 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 3

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207Q00000X

License✔ Licensed in IL · 036156608

Definition

Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.

Also ListedHospitalistTaxonomy 208M00000X · License 036156608 (IL)

Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X · License 125072449 (IL)

2000 OGDEN AVE, Aurora, IL 60504

Open in Google Maps ↗

Secondary Practice Location 1

Location 11325 N Highland AveAurora, IL 60506-1449 · Phone (630) 859-2222

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

John Fox Mast 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 ID6800223710

PECOS Enrollment IDI20210706001423

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 John Mast reassigns Medicare billing to 5 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Rush-Copley Medical Group

Same address

Hematology & Oncology

2000 OGDEN AVENUE
Aurora, IL 60504

Reassigned Medicare billing, Illinois enrollment
Medicare enrollment name: Rush-Copley Medical Group Nfp
171 clinicians in this Medicare group

NPI 1033210364 (630) 978-6250

Kane Physician Services, P.C.

4.9 mi

Internal Medicine

1325 N HIGHLAND AVE
Aurora, IL 60506

Reassigned Medicare billing, Illinois enrollment
Medicare enrollment name: Kane Physician Services PC
33 clinicians in this Medicare group

NPI 1598527483 (630) 859-2222

Rush University Medical Center

20 mi

Internal Medicine

2011 YORK ROAD, 2ND FLOOR
Oak Brook, IL 60523

Reassigned Medicare billing, Illinois enrollment
Medicare enrollment name: Rush University Medical Group
2,169 clinicians in this Medicare group

NPI 1801375696 (630) 724-1310

Prime Healthcare Illinois Medical Group LLC

30 mi

Multi-Specialty

2380 E DEMPSTER ST
Des Plaines, IL 60016

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

NPI 1023837689 (833) 291-0464

Rush Medical Group

33 mi

Internal Medicine

1620 W HARRISON ST
Chicago, IL 60612

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

NPI 1467312850 (312) 942-5000

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 4

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.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233

Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.

405 services123 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.

127 services74 patients

Hospital discharge day management, more than 30 minutes 99239

Hospital discharge day management over 30 minutes involves a detailed process to ensure a smooth transition from hospital to home. It includes final examinations, discussion of your hospital stay, post-discharge instructions, and coordinating follow-up care.

118 services106 patients

Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223

Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.

88 services84 patients

Hospital Affiliations CMS Care Compare 2

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

Copley Memorial Hospital

Acute Care Hospitals · Aurora, IL

4/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number140029

Location2000 Ogden AvenueAurora, IL 60504 · Kane County

Emergency services Birthing friendly

Valley West Community Hospital

Critical Access Hospitals · Sandwich, IL

OwnershipVoluntary non-profit - Private

CMS Certification Number141340

Location1301 North Main StreetSandwich, IL 60548 · De Kalb County

Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60504 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

$93.02 typical visit price

range $59.81 – $181.38

Typical copayment $23.25 (range $14.95 – $45.34)

Most-billed visit code 99203

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.

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.

DR. SAVITHA ALLAM M.D.

Internal Medicine

2000 OGDEN AVE
AURORA, IL 60504

Dupage County (866) 565-8607

FLORIAN WALTER CRNA

Nurse Anesthetist, Certified Registered

2000 OGDEN AVE, RUSH COPLEY MEMORIAL HOSPITAL
AURORA, IL 60504

Dupage County (630) 978-6200

MS. GINGER T. GUINTHER CRNA

Nurse Anesthetist, Certified Registered

2000 OGDEN AVE
AURORA, IL 60504

Dupage County (630) 978-4860

EDWARD C CHEN M.D.

Emergency Medicine

2000 OGDEN AVE, RUSH-COPLEY MEDICAL CENTER, DEPT. OF EMERGENCY SERVICES
AURORA, IL 60504

Dupage County (630) 978-4810

HENRY LEE DO

Student in an Organized Health Care Education/Training Program

2000 OGDEN AVE
AURORA, IL 60504

Dupage County (630) 978-6200

DR. JOSE S SISON MD

Anesthesiology

2000 OGDEN AVE, RUSH COPLEY MEDICAL CENTER
AURORA, IL 60504

Dupage County (630) 978-6200

RD 911, INC

Emergency Medicine

2000 OGDEN AVE
AURORA, IL 60504

Dupage County (630) 978-6200

ALAN ROSENBERG

Emergency Medicine

2000 OGDEN AVE
AURORA, IL 60504

Dupage County (630) 978-4810

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 John Mast's NPI number?

The NPI number for John Mast is 1811488646. It was assigned to this individual provider in the NPPES registry on May 29, 2018.

Where is John Mast located?

John Mast practices at 2000 Ogden Ave, Aurora, IL 60504. The listed phone number is (866) 565-8607.

What is John Mast's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is John Mast enrolled in Medicare?

Yes. John Mast 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 John Mast's services?

According to the CMS Revalidation Reassignment List (October 2026 release), John Mast reassigns Medicare benefits to 5 organizations: Rush-Copley Medical Group (Aurora, IL), Kane Physician Services, P.C. (Aurora, IL), Rush University Medical Center (Oak Brook, IL), Prime Healthcare Illinois Medical Group LLC (Des Plaines, IL) and Rush Medical Group (Chicago, 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 John Mast's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is John Mast affiliated with any hospitals?

According to CMS data, John Mast is affiliated with Copley Memorial Hospital and Valley West Community Hospital.

When was this NPI record last updated?

The NPPES record for John Mast was last updated on September 25, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 12 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.