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GUILLERMO JAVIER ARES MAISONET MD
NPI 1942542105
Surgery - Pediatric Surgery in Maywood, IL

Active since March 25, 2013PECOS EnrolledAccepts Medicare Assignment
2160 S 1ST AVE, MAYWOOD, IL 60153(708) 216-9000 Get Directions Write a Review

NPPES record last updated: August 20, 2026. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Aug 20, 2026, Aug 3, 2026, Oct 14, 2022 and 1 more (4 updates tracked since 2020).

About Guillermo Javier Ares Maisonet Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

GUILLERMO JAVIER ARES MAISONET MD (NPI 1942542105) is an individual pediatric surgery provider in Maywood, Illinois, licensed in Illinois (036139625) and active in the NPI registry since March 2013. He is enrolled in Medicare PECOS, maintains 6 additional practice locations, and is a graduate of Other (2013).

NPPES Registry Identity

NPI1942542105
Entity TypeIndividualMale
Primary Taxonomy2086S0120X
Provider Legal NameGUILLERMO JAVIER ARES MAISONETCredential: MD
Location Address2160 S 1ST AVEMaywood, IL 60153-3328
Mailing Address225 E Chicago AveChicago, IL 60611-2991 · (800) 543-7362
Phone(708) 216-9000
Sole ProprietorYes
Medical School CMSOtherGraduated 2013
Enumeration DateMarch 25, 2013
Last NPPES UpdateAugust 20, 20264 updates tracked since enumeration
NPPES CertifiedAugust 20, 2026
✔ NPI 1942542105 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtySurgery · Pediatric SurgeryAllopathic & Osteopathic Physicians
Taxonomy Code2086S0120X
License✔ Licensed in IL · 036139625
Definition
A surgeon with expertise in the management of surgical conditions in premature and newborn infants, children and adolescents.
2160 S 1ST AVE, Maywood, IL 60153
Open in Google Maps ↗

Other Names 1

Other Name (5)Guillermo Javier Ares Maisonet Md

Secondary Practice Locations 6

Location 11900 Silver Cross BlvdNew Lenox, IL 60451-9509 · Phone (800) 543-7362
Location 21870 Silver Cross BlvdNew Lenox, IL 60451-8639 · Phone (800) 543-7362
Location 325 N Winfield RdWinfield, IL 60190-1379 · Phone (800) 543-7362
Location 4225 E Chicago AveChicago, IL 60611-2991 · Phone (800) 543-7362
Location 52301 Enterprise DrWestchester, IL 60154-5802 · Phone (800) 543-7362
Location 61131 Techny RdNorthbrook, IL 60062-5503 · Phone (800) 543-7362

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

Guillermo Javier Ares Maisonet 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.

PECOS PAC ID143521591
PECOS Enrollment IDI20221024001443
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Guillermo Ares Maisonet reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Lurie Children's Medical Group Inc
11 mi
Pediatrics
225 E CHICAGO AVE
Chicago, IL 60611
  • Reassigned Medicare billing, Illinois enrollment
  • 826 clinicians in this Medicare group
NPI 1518064716 (312) 227-6412

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.

ANITA OZA NAGAMINE M.D.
Radiology (Diagnostic Radiology)
2160 S 1ST AVE
MAYWOOD, IL 60153
Cook County (708) 216-9000
DR. BRYCE ANDREW PASCHOLD D.P.M.
Podiatrist (Foot & Ankle Surgery)
2160 S 1ST AVE
MAYWOOD, IL 60153
Cook County (708) 216-4254
DR. ANTONIO HERNANDO IGLESIAS M.D.
Psychiatry & Neurology (Neurology)
2160 S 1ST AVE
MAYWOOD, IL 60153
Cook County (708) 216-9000
IAN CHARLES MCCOMB
Oral & Maxillofacial Surgery
2160 S 1ST AVE
MAYWOOD, IL 60153
Cook County (708) 216-9000
JAMES WU D.O.
Psychiatry & Neurology (Psychiatry)
2160 S 1ST AVE
MAYWOOD, IL 60153
Cook County (708) 216-9000
PAIGE T SONG MD
Student in an Organized Health Care Education/Training Program
2160 S 1ST AVE
MAYWOOD, IL 60153
Cook County (888) 584-7888
ELIZABETH CHO
Orthopaedic Surgery
2160 S 1ST AVE
MAYWOOD, IL 60153
Cook County (708) 216-1274
DR. CATHRYN T SAWALSKI DO, MBA
Internal Medicine
2160 S 1ST AVE
MAYWOOD, IL 60153
Cook County (888) 584-7888

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 Guillermo Ares Maisonet's NPI number?

The NPI number for Guillermo Ares Maisonet is 1942542105. It was assigned to this individual provider in the NPPES registry on March 25, 2013. The provider is also known as Guillermo Javier Ares Maisonet MD.

Where is Guillermo Ares Maisonet located?

Guillermo Ares Maisonet practices at 2160 S 1st Ave, Maywood, IL 60153. The listed phone number is (708) 216-9000.

What is Guillermo Ares Maisonet's specialty?

The primary specialty registered for this NPI is Surgery, specializing in Pediatric Surgery, with taxonomy code 2086S0120X.

Is Guillermo Ares Maisonet enrolled in Medicare?

Yes. Guillermo Ares Maisonet 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 Guillermo Ares Maisonet's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Guillermo Ares Maisonet reassigns Medicare benefits to Lurie Children's Medical Group Inc (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 Guillermo Ares Maisonet'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 Guillermo Ares Maisonet was last updated on August 20, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.