DR. ROSS HOWARD MCMILLAN MD
NPI 1578099578
Internal Medicine - Gastroenterology in Chicago, IL
About Dr. Ross Howard Mcmillan Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. ROSS HOWARD MCMILLAN MD (NPI 1578099578) is an individual gastroenterology provider in Chicago, Illinois, licensed in Illinois (036156732) and active in the NPI registry since May 2017. He is enrolled in Medicare PECOS, is affiliated with The University Of Chicago Medical Center, and is a graduate of Johns Hopkins University School Of Medicine (2018).
NPPES Registry Identity
Specialties & Licenses 3
Accepted 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
Dr. Ross Howard Mcmillan 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.
Medicare Billing Reassignments
2Medicare enrollment records show Ross Mcmillan reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Chicago, IL 60637
- Reassigned Medicare billing, Illinois enrollment
- 1,905 clinicians in this Medicare group
Chicago, IL 60637
- Reassigned Medicare billing, Illinois and Indiana enrollments
- 2,237 clinicians in this Medicare group
Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
The University Of Chicago Medical Center
Acute Care Hospitals · Chicago, ILPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 60637 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
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.
CHICAGO, IL 60637
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 Ross Mcmillan's NPI number?
The NPI number for Ross Mcmillan is 1578099578. It was assigned to this individual provider in the NPPES registry on May 11, 2017.
Where is Ross Mcmillan located?
Ross Mcmillan practices at 5841 S Maryland Ave, Chicago, IL 60637. The listed phone number is (888) 824-0200.
What is Ross Mcmillan's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.
Is Ross Mcmillan enrolled in Medicare?
Yes. Ross Mcmillan 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 Ross Mcmillan's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Ross Mcmillan reassigns Medicare benefits to 2 organizations: The University Of Chicago Medical Center (Chicago, IL) and University Of Chicago (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 Ross Mcmillan's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Ross Mcmillan accept?
Health plans from Oscar Health list Ross Mcmillan 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 Ross Mcmillan affiliated with any hospitals?
According to CMS data, Ross Mcmillan is affiliated with The University Of Chicago Medical Center.
When was this NPI record last updated?
The NPPES record for Ross Mcmillan was last updated on September 5, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 14 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.
# Dr. Ross Howard Mcmillan, MD · NPI 1578099578
Gastroenterology physician in Chicago, Illinois. Individual provider, active in the CMS NPPES registry since May 11, 2017.
## Identity
- **NPI:** 1578099578 (Entity type: Individual)
- **Enumerated:** May 11, 2017
- **Primary specialty:** Internal Medicine - Gastroenterology · taxonomy 207RG0100X
- **State license:** 036156732 (Illinois)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 5841 S MARYLAND AVE, Chicago, IL 60637-1443
- **Phone:** (888) 824-0200
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 2 organizations under Medicare reassignment (form CMS-855R): The University Of Chicago Medical Center (NPI 1033218128, Chicago, IL); University Of Chicago (NPI 1821048786, Chicago, IL) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Johns Hopkins University School Of Medicine, class of 2018
## Record status
- **NPPES last updated:** September 5, 2025
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Source: [NPI Profile](https://npiprofile.com/npi/1578099578) · Data from the CMS NPPES public registry.