Dr. Cassidy Williams, DO
- Part D claims, 2026
- 11
- Industry payments
- $1,755
- State license
- 1
- Year NPI issued
- 2022
- Practice address
- 1653 W Congress Pkwy, Chicago, IL 60612
- Practice phone
- Call (312) 942-5000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Rush University &Medical Center
Chicago, Illinois
Find Dr. Williams' 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.
Dr. Cassidy Williams is a general surgeon in Chicago, Illinois
Dr. Williams practices at Rush University &Medical Center in Chicago, Illinois.
Dr. Williams' NPI, 1578211140, was assigned on March 14, 2022. Dr. Williams holds Illinois license 125.082539.
- NPI
- 1578211140NPI Registry (opens in a new tab)
- NPI enumeration date
- March 14, 2022
- NPI status
- Active
- Practice phone
- (312) 942-5000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Female
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Practice Data
Dr. Cassidy Williams practices at Rush University &Medical Center in Chicago, Illinois
Dr. Williams' primary practice is Rush University &Medical Center, at 1653 W Congress Pkwy, Chicago, IL 60612 in Cook County. The practice phone is (312) 942-5000.
- Rush University &Medical Center1653 W Congress Pkwy, Chicago, IL 60612 · Cook CountyPhone(312) 942-5000
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dr. Cassidy Williams is affiliated with 1 site of care
Dr. Williams' primary practice is Rush University &Medical Center in Chicago, Illinois.
Sources: NPPES NPI Registry (CMS); and Dmand AI Practice Data
Dmand AI tracks the EHR system at Dr. Cassidy Williams' practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Williams practices. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Rush University &Medical Center | Available with a free account |
Source: Dmand AI Technology Install Data
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Dr. Cassidy Williams is one of 1,217 general surgeons in Illinois
Surgery is Dr. Williams' primary specialty in the NPI Registry, under taxonomy code 208600000X. Dr. Williams is licensed in Illinois.
Specialties and state licenses
- Surgery, IllinoisPrimary
General surgeons near Dr. Williams
Counts of general surgeons 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
Dr. Cassidy Williams' patients have a median age of 75
Across all payers, Dmand AI patient panel data puts Dr. Williams' median patient age at 75, with 0% women.
Dr. Williams' patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 75
Patient panel by sex, all payers
- Women0%
- Men100%
Source: Dmand AI Patient Panel Data
Dr. Cassidy Williams wrote 11 Medicare Part D claims in 2026
In 2026, Dr. Williams wrote 11 Medicare Part D claims. 100% of them were for generic drugs.
Source: Medicare Part D Prescribers - by Provider (CMS), 2026 data
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Dr. Cassidy Williams received $1,755 in industry payments from 2023 to 2025
CMS Open Payments shows 20 general payments to Dr. Williams from 6 drug and device companies from 2023 to 2025. Food and beverage make up the largest share, 100% of the total. Boston Scientific Corporation paid the most, $903.
General payments to Dr. Williams by program year, 2023 to 2025
Companies that paid Dr. Williams the most, 2023 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Sources for Dr. Cassidy Williams'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 | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Primary practice, affiliations and health system | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Practice Data |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel Data |
| Part D prescribing | Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| 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 Dr. Cassidy Williams
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Cassidy Williams' NPI number?
Dr. Cassidy Williams' NPI number is 1578211140. It was assigned on March 14, 2022, and it is active in the NPI Registry.
What kind of doctor is Dr. Cassidy Williams?
Dr. Cassidy Williams is a general surgeon in Chicago, Illinois. The primary specialty in the NPI Registry is Surgery Physician (taxonomy code 208600000X).
Where does Dr. Cassidy Williams practice?
Dr. Williams practices at 1653 W Congress Pkwy, Chicago, IL 60612. Dr. Williams' primary practice is Rush University &Medical Center in Chicago, Illinois.
What is Dr. Cassidy Williams' office phone number?
The practice phone on file for Dr. Williams is (312) 942-5000. Dmand AI also checks direct phone and mobile numbers, available with a free account.
What is Dr. Cassidy Williams' email address?
Dmand AI checks professional and personal email addresses for Dr. Williams through healthcare-specific waterfall enrichment. They are available with a free Dmand AI account.
What is Dr. Cassidy Williams' medical license number?
Dr. Williams holds Illinois license 125.082539.
Has Dr. Cassidy Williams received payments from drug or device companies?
CMS Open Payments shows $1,755 in general payments to Dr. Williams from 6 companies from 2023 to 2025. The largest total came from Boston Scientific Corporation.
How long has Dr. Cassidy Williams been practicing?
Dr. Williams' NPI was assigned in 2022.
What EHR does Dr. Cassidy Williams' practice use?
Dmand AI tracks the EHR system at Rush University &Medical Center. The vendor and product are available with a free Dmand AI account.
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