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MARI MORTENSEN LCSW
NPI 1578276770
Social Worker - Clinical in Darien, IL

Active since January 03, 2023PECOS Enrolled
9265 WATERFALL GLEN BLVD, DARIEN, IL 60561(708) 650-4356 Get Directions Write a Review

NPPES record last updated: July 31, 2024. Verified against the NPPES registry weekly; last sync: November 08, 2026.

Record update history: Jul 31, 2024, Jan 3, 2023 (2 updates tracked since 2023).

About Mari Mortensen Lcsw NPPES

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

MARI MORTENSEN LCSW (NPI 1578276770) is an individual clinical provider in Darien, Illinois and active in the NPI registry since January 2023. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1578276770
Entity TypeIndividualFemale
Primary Taxonomy1041C0700X
Provider Legal NameMARI MORTENSENCredential: LCSW
Location Address9265 WATERFALL GLEN BLVDDarien, IL 60561-5282
Mailing Address9265 Waterfall Glen BlvdDarien, IL 60561-5282 · (708) 650-4356
Phone(708) 650-4356
Sole ProprietorYes
Enumeration DateJanuary 3, 2023
Last NPPES UpdateJuly 31, 20242 updates tracked since enumeration
NPPES CertifiedJuly 31, 2024
✔ NPI 1578276770 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtySocial Worker · ClinicalBehavioral Health & Social Service Providers
Taxonomy Code1041C0700X
Definition
A social worker who holds a master's or doctoral degree in social work from an accredited school of social work in addition to at least two years of post-master's supervised experience in a clinical setting. The social worker must be licensed, certified, or registered at the clinical level in the jurisdiction of practice. A clinical social worker provides direct services, including interventions focused on interpersonal interactions, intrapsychic dynamics, and life management issues. Clinical social work services are based on bio-psychosocial perspectives. Services consist of assessment, diagnosis, treatment (including psychotherapy and counseling), client-centered advocacy, consultation, evaluation, and prevention of mental illness, emotional, or behavioral disturbances.
9265 WATERFALL GLEN BLVD, Darien, IL 60561
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Mari Mortensen Lcsw is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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 Mari Mortensen reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Mari Mortensen Lcsw PLLC
15 mi
Clinical
101 N MARION ST STE 300
Oak Park, IL 60301
  • Reassigned Medicare billing, Illinois enrollment
NPI 1780412403 (708) 650-4356

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 60561 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
$0.00 typical visit price
range $59.81 – $181.38
Typical copayment $0.00 (range $14.95 – $45.34)
Most-billed visit code NA
Established Patient
$74.38 typical visit price
range $19.15 – $147.12
Typical copayment $18.59 (range $4.78 – $36.78)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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 Mari Mortensen's NPI number?

The NPI number for Mari Mortensen is 1578276770. It was assigned to this individual provider in the NPPES registry on January 3, 2023.

Where is Mari Mortensen located?

Mari Mortensen practices at 9265 Waterfall Glen Blvd, Darien, IL 60561. The listed phone number is (708) 650-4356.

What is Mari Mortensen's specialty?

The primary specialty registered for this NPI is Social Worker, specializing in Clinical, with taxonomy code 1041C0700X.

Is Mari Mortensen enrolled in Medicare?

Yes. Mari Mortensen is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Mari Mortensen's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mari Mortensen reassigns Medicare benefits to Mari Mortensen Lcsw PLLC (Oak Park, 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 Mari Mortensen'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 Mari Mortensen was last updated on July 31, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.