MATHIAS JAMES LILLIG MD
NPI 1235344433
Psychiatry & Neurology - Child & Adolescent Psychiatry in Chicago, IL
About Mathias James Lillig Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MATHIAS JAMES LILLIG MD (NPI 1235344433) is an individual child & adolescent psychiatry provider in Chicago, Illinois, licensed in Illinois (036.112778) and active in the NPI registry since May 2007. He is enrolled in Medicare PECOS and maintains a secondary practice location in Chicago.
NPPES Registry Identity
Specialties & Licenses 2
Secondary Practice Location 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Mathias James Lillig Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignment
Medicare enrollment records show Mathias Lillig reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Chicago, IL 60612
- Reassigned Medicare billing, Illinois enrollment
- 49 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.
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 60608
CHICAGO, IL 60608
CHICAGO, IL 60608
CHICAGO, IL 60608
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 Mathias Lillig's NPI number?
The NPI number for Mathias Lillig is 1235344433. It was assigned to this individual provider in the NPPES registry on May 11, 2007.
Where is Mathias Lillig located?
Mathias Lillig practices at 1747 W Roosevelt Rd, Chicago, IL 60608. The listed phone number is (312) 996-2200.
What is Mathias Lillig's specialty?
The primary specialty registered for this NPI is Psychiatry & Neurology, specializing in Child & Adolescent Psychiatry, with taxonomy code 2084P0804X.
Is Mathias Lillig enrolled in Medicare?
Yes. Mathias Lillig is registered in the Medicare PECOS enrollment system.
Which organization bills Medicare for Mathias Lillig's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mathias Lillig reassigns Medicare benefits to The Board Of Trustees Of The University Of Illinois (Chicago, IL). The 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 Mathias Lillig's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Mathias Lillig was last updated on November 8, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 23 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.
# Mathias James Lillig, MD · NPI 1235344433
Child & Adolescent Psychiatry physician in Chicago, Illinois. Individual provider, active in the CMS NPPES registry since May 11, 2007.
## Identity
- **NPI:** 1235344433 (Entity type: Individual)
- **Enumerated:** May 11, 2007
- **Primary specialty:** Psychiatry & Neurology - Child & Adolescent Psychiatry · taxonomy 2084P0804X
- **State license:** 036.112778 (Illinois)
- **Sole proprietor:** No
## Practice location
- **Address:** 1747 W ROOSEVELT RD, Chicago, IL 60608-1264
- **Phone:** (312) 996-2200
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** The Board Of Trustees Of The University Of Illinois (NPI 1609822147, Chicago, IL), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** November 8, 2024
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Source: [NPI Profile](https://npiprofile.com/npi/1235344433) · Data from the CMS NPPES public registry.