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OLESIA SHALAYSKA
NPI 1558816371
Psychologist - Clinical in Warrenville, IL

Active since August 22, 2016PECOS EnrolledAccepts Medicare Assignment
4320 WINFIELD RD STE 200, WARRENVILLE, IL 60555(630) 686-8875(630) 686-5445 Get Directions Write a Review

NPPES record last updated: April 7, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Apr 7, 2026, Jul 2, 2025, Nov 2, 2018 and 1 more (4 updates tracked since 2016).

About Olesia Shalayska NPPES

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

OLESIA SHALAYSKA (NPI 1558816371) is an individual clinical provider in Warrenville, Illinois, licensed in Indiana (20042972A) and active in the NPI registry since August 2016. She is enrolled in Medicare PECOS, maintains a secondary practice location in Palos Heights, and is a graduate of Other (2012).

NPPES Registry Identity

NPI1558816371
Entity TypeIndividualFemale
Primary Taxonomy103TC0700X
Provider Legal NameOLESIA SHALAYSKA
Location Address4320 WINFIELD RD STE 200Warrenville, IL 60555-4023
Mailing Address21w043 Kensington RdLombard, IL 60148-5116 · (630) 536-9444 · Fax (630) 686-5445
Phone(630) 686-8875
Fax(630) 686-5445
Sole ProprietorNo
Medical School CMSOtherGraduated 2012
Enumeration DateAugust 22, 2016
Last NPPES UpdateApril 7, 20264 updates tracked since enumeration
NPPES CertifiedApril 7, 2026
✔ NPI 1558816371 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPsychologist · ClinicalBehavioral Health & Social Service Providers
Taxonomy Code103TC0700X
License✔ Licensed in IN · 20042972A
Definition
A psychologist who provides continuing and comprehensive mental and behavioral health care for individuals and families; consultation to agencies and communities; training, education and supervision; and research-based practice. It is a specialty in breadth -- one that is broadly inclusive of severe psychopathology -- and marked by comprehensiveness and integration of knowledge and skill from a broad array of disciplines within and outside of psychology proper. The scope of clinical psychology encompasses all ages, multiple diversities and varied systems.
4320 WINFIELD RD STE 200, Warrenville, IL 60555
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Secondary Practice Location 1

Location 17110 W 127th St Ste 150Palos Heights, IL 60463-1579 · Phone (630) 686-8875 · Fax (630) 686-5445

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Oscar Health.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

Olesia Shalayska 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 ID8224324017
PECOS Enrollment IDI20180820002153
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 Reassignments

3

Medicare enrollment records show Olesia Shalayska reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Peace Of Mind Psychological Services Inc
Same address
Clinical
4320 WINFIELD RD STE 200
Warrenville, IL 60555
  • Reassigned Medicare billing, Illinois enrollment
NPI 1427661685 (630) 465-9030
Michael Pica P.C.
15 mi
Psychologist
4N701 SCHOOL RD STE A
St Charles, IL 60175
  • Reassigned Medicare billing, Illinois enrollment
  • Medicare enrollment name: Michael Pica PC
  • 3 clinicians in this Medicare group
NPI 1730449315 (630) 549-6497
Behavioral Healthcare Providers Ltd
16 mi
Multi-Specialty
1375 E SCHAUMBURG RD STE 240
Schaumburg, IL 60194
  • Reassigned Medicare billing, Illinois enrollment
  • 12 clinicians in this Medicare group
NPI 1043781958 (847) 895-4540

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 2

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.

Psychotherapy, 45 minutes 90834
Psychotherapy is a treatment method where you converse with a therapist about your thoughts, feelings, and behaviors. In a 45-minute session, the therapist assists you in understanding and managing your mental health concerns, improving emotional wellness, and promoting personal growth.
178 services16 patients
Psychotherapy, 30 minutes 90832
Psychotherapy is a therapeutic interaction or treatment between a trained professional and a patient. In a 30-minute session, the therapist helps you explore feelings, thoughts, and behaviors to better understand yourself and manage life's challenges.
36 services13 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 60555 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$181.38 typical visit price
range $59.81 – $181.38
Typical copayment $45.34 (range $14.95 – $45.34)
Most-billed visit code 99205
Established Patient
$105.07 typical visit price
range $19.15 – $147.12
Typical copayment $26.26 (range $4.78 – $36.78)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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.

JACQUELINE OROZCO LCSW
Social Worker (Clinical)
4320 WINFIELD RD STE 200
WARRENVILLE, IL 60555
Dupage County (312) 801-5100
ANGELA ZABA
Nurse Practitioner (Psychiatric/Mental Health)
4320 WINFIELD RD STE 200
WARRENVILLE, IL 60555
Dupage County (630) 333-4718
RELATIONAL METHOD PLLC
Marriage & Family Therapist
4320 WINFIELD RD STE 200
WARRENVILLE, IL 60555
Dupage County (708) 918-4293
1ST JUVENANT CARE LLC
Home Health
4320 WINFIELD RD STE 200
WARRENVILLE, IL 60555
Dupage County (773) 249-4377
THERESE JANUS
Counselor (Mental Health)
4320 WINFIELD RD STE 200
WARRENVILLE, IL 60555
Dupage County (630) 686-8875
ALAYNA GAJEWSKI
Physical Therapist
4320 WINFIELD RD STE 200
WARRENVILLE, IL 60555
Dupage County (877) 407-3422
S & J WELLNESS PLLC
Counselor (Mental Health)
4320 WINFIELD RD STE 200
WARRENVILLE, IL 60555
Dupage County (815) 782-2172
ABANTU HOME SERVICES LLC
Home Health
4320 WINFIELD RD STE 200
WARRENVILLE, IL 60555
Dupage County (773) 382-1752

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 Olesia Shalayska's NPI number?

The NPI number for Olesia Shalayska is 1558816371. It was assigned to this individual provider in the NPPES registry on August 22, 2016.

Where is Olesia Shalayska located?

Olesia Shalayska practices at 4320 Winfield Rd Ste 200, Warrenville, IL 60555. The listed phone number is (630) 686-8875.

What is Olesia Shalayska's specialty?

The primary specialty registered for this NPI is Psychologist, specializing in Clinical, with taxonomy code 103TC0700X.

Is Olesia Shalayska enrolled in Medicare?

Yes. Olesia Shalayska 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 Olesia Shalayska's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Olesia Shalayska reassigns Medicare benefits to 3 organizations: Peace Of Mind Psychological Services Inc (Warrenville, IL), Michael Pica P.C. (St Charles, IL) and Behavioral Healthcare Providers Ltd (Schaumburg, 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 Olesia Shalayska's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Olesia Shalayska accept?

Health plans from Oscar Health list Olesia Shalayska 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.

When was this NPI record last updated?

The NPPES record for Olesia Shalayska was last updated on April 7, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.