DR. DENNIS ALAN PEACOCK MD
NPI 1023223021
Internal Medicine in Chicago, IL
About Dr. Dennis Alan Peacock Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. DENNIS ALAN PEACOCK MD (NPI 1023223021) is an individual internal medicine provider in Chicago, Illinois, licensed in Illinois (036.141382) and active in the NPI registry since May 2007. He is enrolled in Medicare PECOS, is affiliated with Loyola University Medical Center, and maintains a secondary practice location in Chicago.
NPPES Registry Identity
Specialties & Licenses 2
Secondary Practice Location 1
Other Identifiers 2
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. Dennis Alan Peacock 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 Reassignment
Medicare enrollment records show Dennis Peacock reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Maywood, IL 60153
- Reassigned Medicare billing, Illinois enrollment
- 1,138 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.
Areas of Expertise CMS Part B claims 5
Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Loyola University Medical Center
Acute Care Hospitals · Maywood, ILPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 60657 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 4
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
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 Dennis Peacock's NPI number?
The NPI number for Dennis Peacock is 1023223021. It was assigned to this individual provider in the NPPES registry on May 11, 2007.
Where is Dennis Peacock located?
Dennis Peacock practices at 1333 W Belmont Ave Ste 100, Chicago, IL 60657. The listed phone number is (312) 694-2273.
What is Dennis Peacock's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is Dennis Peacock enrolled in Medicare?
Yes. Dennis Peacock 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 organization bills Medicare for Dennis Peacock's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Dennis Peacock reassigns Medicare benefits to Loyola University Medical Center (Maywood, 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 Dennis Peacock's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Dennis Peacock accept?
Health plans from Oscar Health list Dennis Peacock 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 Dennis Peacock affiliated with any hospitals?
According to CMS data, Dennis Peacock is affiliated with Loyola University Medical Center.
When was this NPI record last updated?
The NPPES record for Dennis Peacock was last updated on May 27, 2022. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.
# Dr. Dennis Alan Peacock, MD · NPI 1023223021
Internal Medicine physician in Chicago, Illinois. Individual provider, active in the CMS NPPES registry since May 11, 2007.
## Identity
- **NPI:** 1023223021 (Entity type: Individual)
- **Enumerated:** May 11, 2007
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** 036.141382 (Illinois)
- **Sole proprietor:** No
## Practice location
- **Address:** 1333 W BELMONT AVE STE 100, Chicago, IL 60657
- **Phone:** (312) 694-2273 · **Fax:** (312) 694-1875
## 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:** Loyola University Medical Center (NPI 1336159961, Maywood, IL), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Tennessee, Hsc, College Of Medicine, class of 2004
## Record status
- **NPPES last updated:** May 27, 2022
- **Other identifiers:** Medicaid 05024018 (MS); Medicaid 1073849 (LA)
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Source: [NPI Profile](https://npiprofile.com/npi/1023223021) · Data from the CMS NPPES public registry.