Mainstay Clinics Inc
NPI 1134622053 · Nurse Practitioner · Libertyville, IL
Enrolled with Medicare as Part B Supplier - Clinic/Group Practice · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Mainstay Clinics Inc is a Nurse Practitioner organization in Libertyville, IL (NPI 1134622053).
Provider details
- NPI number
- 1134622053
- Entity type
- Organization
- Primary specialty
- Nurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
- Organization subpart
- No
- Authorized official
- Alexander Jarosz, Officer(224) 717-0447
- License
- 209009332 (IL)
Specialties & taxonomies
Physician Assistants & Advanced Practice Nursing Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
8 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
Practice location
Mailing address
Registry dates
- Enumerated
- 2018-03-16
- Last updated
- 2025-08-29
- Certified
- 2025-08-29
Frequently asked questions
- What is Mainstay Clinics Inc's NPI number?
- Mainstay Clinics Inc's National Provider Identifier (NPI) is 1134622053, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What type of organization is Mainstay Clinics Inc?
- Mainstay Clinics Inc is classified in the NPPES registry as Nurse Practitioner (Physician Assistants & Advanced Practice Nursing Providers).
- Where is Mainstay Clinics Inc located?
- Mainstay Clinics Inc's practice location on file with NPPES is 333 Peterson Rd Ste 240, Libertyville, IL 60048-1085.
- What is Mainstay Clinics Inc's phone number?
- The practice phone number listed in the NPPES registry for Mainstay Clinics Inc is (224) 864-2124.
- Does Mainstay Clinics Inc accept Medicare?
- Mainstay Clinics Inc is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Who is the authorized official for Mainstay Clinics Inc?
- The authorized official listed on Mainstay Clinics Inc's NPPES record is Alexander Jarosz, Officer. The authorized official registers and maintains the organization's NPI and is not necessarily its owner.
- Is Mainstay Clinics Inc's NPI active?
- Yes — Mainstay Clinics Inc's NPI (1134622053) is active in the NPPES registry as of the last update on 2025-08-29.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.