Mary E. Wassilak, Whnpbc
- Hospital affiliations
- 1
- Industry payments
- $40
- Medical group
- 1
- State license
- 1
- Year NPI issued
- 2009
- Practice address
- 25 North Winfield Road, Winfield, IL 60190
- Practice phone
- Call (630) 682-1600
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Find Mary Wassilak's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Mary E. Wassilak is a nurse practitioner in Winfield, Illinois
Mary Wassilak practices at Northwestern Medicine Central DuPage Hospital in Winfield, Illinois, part of Northwestern Memorial HealthCare.
Mary Wassilak's NPI, 1811138944, was assigned on March 19, 2009. Mary Wassilak graduated from University of Illinois College of Med (Chi/Peor/Rock/Chm-Urb) in 2007. Mary Wassilak holds Illinois license 209006774.
- NPI
- 1811138944NPI Registry (opens in a new tab)
- Medicare PAC ID
- 8022295666
- NPI enumeration date
- March 19, 2009
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (630) 682-1600
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Female
- Estimated age
- 45
- Medical school graduation
- 2007
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Mary E. Wassilak practices at Northwestern Medicine Central DuPage Hospital in Winfield, Illinois
Mary Wassilak's primary practice is Northwestern Medicine Central DuPage Hospital, at 25 North Winfield Road, Winfield, IL 60190 in Du Page County. The practice phone is (630) 682-1600.
- Northwestern Medicine Central DuPage Hospital25 North Winfield Road, Winfield, IL 60190 · Du Page CountyPhone(630) 682-1600
Source: Dmand AI Affiliation Data
Mary E. Wassilak is affiliated with 4 sites of care and 1 medical group
Mary Wassilak's primary practice is Northwestern Medicine Central DuPage Hospital in Winfield, Illinois, part of Northwestern Memorial HealthCare. The medical group on file is Northwestern Medicine Regional Medical Group. Dmand AI also links Mary Wassilak to 1 more breast imaging center, 1 clinical lab and 1 group practice or clinic, each named with a free account.
Sources: Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Mary E. Wassilak's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Mary Wassilak practices, 4 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Northwestern Medicine Central DuPage Hospital | Available with a free account |
| +3 more affiliated sites | Available with a free account |
Source: Dmand AI Technology Install Data
For health IT teams
Dmand AI maps EHR vendors, IT decision makers and buying committees across Northwestern Memorial HealthCare and 6.2K+ hospitals, with verified contacts in the same login.
Mary E. Wassilak is one of 4,254 nurse practitioners in Illinois
Nurse practitioner is Mary Wassilak's primary specialty in the NPI Registry, under taxonomy code 363L00000X. Mary Wassilak is licensed in Illinois.
Specialties and state licenses
- Nurse practitioner, IllinoisPrimary
Nurse practitioners near Mary Wassilak
Counts of nurse practitioners with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Mary E. Wassilak's patients have a median age of 33
Across all payers, Dmand AI patient panel data puts Mary Wassilak's median patient age at 33, with 99% women.
Mary Wassilak's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 33
Patient panel by sex, all payers
- Women99%
- Men0%
Source: Dmand AI Patient Panel Data
How Mary E. Wassilak takes part in Medicare
Mary Wassilak accepts Medicare assignment, so Medicare's approved amount is taken as full payment.
- Accepts Medicare assignment
- Yes
Source: Doctors and Clinicians National Downloadable File (CMS)
Mary E. Wassilak received $40 in industry payments in 2025
CMS Open Payments shows 1 general payment to Mary Wassilak from 1 drug or device company in 2025. Food and beverage make up the largest share, 100% of the total. Sumitomo Pharma America, Inc. paid the most, $40.
Companies that paid Mary Wassilak the most, 2025 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Mary E. Wassilak graduated from University of Illinois College of Med (Chi/Peor/Rock/Chm-Urb)
Mary Wassilak graduated from University of Illinois College of Med (Chi/Peor/Rock/Chm-Urb) in 2007.
- Medical school
Source: Dmand AI Professional Profile Data
Sources for Mary E. Wassilak's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | Dmand AI Affiliation Data |
| Primary practice, affiliations and health system | Dmand AI Affiliation DataDmand AI Org Hierarchy Data |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel Data |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Mary E. Wassilak
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Mary E. Wassilak's NPI number?
Mary E. Wassilak's NPI number is 1811138944. It was assigned on March 19, 2009, and it is active in the NPI Registry.
What does Mary E. Wassilak specialize in?
Mary E. Wassilak is a nurse practitioner in Winfield, Illinois. The primary specialty in the NPI Registry is Nurse Practitioner (taxonomy code 363L00000X).
Where does Mary E. Wassilak practice?
Mary Wassilak practices at 25 North Winfield Road, Winfield, IL 60190. Mary Wassilak's primary practice is Northwestern Medicine Central DuPage Hospital in Winfield, Illinois, part of Northwestern Memorial HealthCare. Dmand AI also links Mary Wassilak to 1 breast imaging center, 1 clinical lab and 1 group practice or clinic.
What is Mary E. Wassilak's office phone number?
The practice phone on file for Mary Wassilak is (630) 682-1600.
What is Mary E. Wassilak's medical license number?
Mary Wassilak holds Illinois license 209006774.
Which hospitals is Mary E. Wassilak affiliated with?
Mary Wassilak practices at Northwestern Medicine Central DuPage Hospital in Winfield, Illinois.
What medical group is Mary E. Wassilak part of?
Mary Wassilak is linked to Northwestern Medicine Regional Medical Group.
Does Mary E. Wassilak accept Medicare?
Yes. CMS lists Mary Wassilak as accepting Medicare assignment.
Where did Mary E. Wassilak go to medical school?
Mary Wassilak graduated from University of Illinois College of Med (Chi/Peor/Rock/Chm-Urb) in 2007.
Has Mary E. Wassilak received payments from drug or device companies?
CMS Open Payments shows $40 in general payments to Mary Wassilak from 1 company from 2025 to 2025. The largest total came from Sumitomo Pharma America, Inc.
How long has Mary E. Wassilak been practicing?
Mary Wassilak graduated from medical school in 2007, 19 years ago.
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