HERBERT SIER MD
NPI 1881627446
Internal Medicine - Geriatric Medicine in Chicago, IL
About Herbert Sier Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
HERBERT SIER MD (NPI 1881627446) is an individual geriatric medicine provider in Chicago, Illinois and active in the NPI registry since July 2006. He is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Herbert Sier Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
2Medicare enrollment records show Herbert Sier reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Orange, CA 92868
- Reassigned Medicare billing, California enrollment
- 114 clinicians in this Medicare group
Orange, CA 92868
- Reassigned Medicare billing, California enrollment
- 525 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.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 60611 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 60611
CHICAGO, IL 60611
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 Herbert Sier's NPI number?
The NPI number for Herbert Sier is 1881627446. It was assigned to this individual provider in the NPPES registry on July 8, 2006.
Where is Herbert Sier located?
Herbert Sier practices at 680 N Lake Shore Dr Suite 1000, Chicago, IL 60611. The listed phone number is (312) 695-9797.
What is Herbert Sier's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Geriatric Medicine, with taxonomy code 207RG0300X.
Is Herbert Sier enrolled in Medicare?
Yes. Herbert Sier is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Herbert Sier's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Herbert Sier reassigns Medicare benefits to 2 organizations: Regents Of The University Of (Orange, CA) and Uc Regents (Orange, CA). 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 Herbert Sier'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 Herbert Sier was last updated on July 8, 2007. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 19 years 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.
# Herbert Sier, MD · NPI 1881627446
Geriatric Medicine physician in Chicago, Illinois. Individual provider, active in the CMS NPPES registry since July 8, 2006.
## Identity
- **NPI:** 1881627446 (Entity type: Individual)
- **Enumerated:** July 8, 2006
- **Primary specialty:** Internal Medicine - Geriatric Medicine · taxonomy 207RG0300X
- **Sole proprietor:** No
## Practice location
- **Address:** 680 N LAKE SHORE DR, SUITE 1000, Chicago, IL 60611-4546
- **Phone:** (312) 695-9797
## 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:** 2 organizations under Medicare reassignment (form CMS-855R): Regents Of The University Of (NPI 1366590762, Orange, CA); Uc Regents (NPI 1003864174, Orange, CA) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** July 8, 2007
- **Other identifiers:** Medicare UPIN D16380
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Source: [NPI Profile](https://npiprofile.com/npi/1881627446) · Data from the CMS NPPES public registry.