MARK FARRELL O'BRIEN MS, LCPC
NPI 1932427986
Counselor - Professional in Chicago, IL

Q: What is Mark O'brien's NPI number?

The NPI number for Mark O'brien is 1932427986. It was assigned to this individual provider in the NPPES registry on May 13, 2010.

Q: What is Mark O'brien's specialty?

The primary specialty registered for this NPI is Counselor, specializing in Professional, with taxonomy code 101YP2500X.

Q: When was this NPI record last updated?

The NPPES record for Mark O'brien was last updated on September 20, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.

Active since May 13, 2010

605 N MICHIGAN AVE FL 4, CHICAGO, IL 60611 Get Directions Write a Review

NPPES record last updated: September 20, 2019. Verified against the NPPES registry weekly; last sync: August 16, 2026.

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About Mark Farrell O'brien Ms, Lcpc NPPES

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

MARK FARRELL O'BRIEN MS, LCPC (NPI 1932427986) is an individual professional provider in Chicago, Illinois, licensed in Illinois (180008079) and active in the NPI registry since May 2010.

NPPES Registry Identity

NPI1932427986

Entity TypeIndividualMale

Primary Taxonomy101YP2500X

Provider Legal NameMARK FARRELL O'BRIENCredential: MS, LCPC

Location Address605 N MICHIGAN AVE FL 4Chicago, IL 60611-3141

Mailing Address605 N Michigan Ave Fl 4Chicago, IL 60611-3141 · (312) 316-7703

Sole ProprietorYes

Enumeration DateMay 13, 2010

Last NPPES UpdateSeptember 20, 2019

✔ NPI 1932427986 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyCounselor · ProfessionalBehavioral Health & Social Service Providers

Taxonomy Code101YP2500X

License✔ Licensed in IL · 180008079

605 N MICHIGAN AVE FL 4, Chicago, IL 60611

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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.

DELILAH ORTIZ LCSW

Social Worker

605 N MICHIGAN AVE FL 4
CHICAGO, IL 60611

Cook County (773) 217-0651

DR. YVONNE M. PATTERSON, LLC

Clinic/Center (Adult Mental Health)

605 N MICHIGAN AVE FL 4
CHICAGO, IL 60611

Cook County (312) 805-5523

SOPHIA JULIO

Counselor (Mental Health)

605 N MICHIGAN AVE FL 4
CHICAGO, IL 60611

Cook County (773) 964-7191

MEGAN MURPHY LCSW

Social Worker (Clinical)

605 N MICHIGAN AVE FL 4
CHICAGO, IL 60611

Cook County (217) 439-4255

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 Mark O'brien's NPI number?

The NPI number for Mark O'brien is 1932427986. It was assigned to this individual provider in the NPPES registry on May 13, 2010.

Where is Mark O'brien located?

Mark O'brien practices at 605 N Michigan Ave Fl 4, Chicago, IL 60611.

What is Mark O'brien's specialty?

The primary specialty registered for this NPI is Counselor, specializing in Professional, with taxonomy code 101YP2500X.

When was this NPI record last updated?

The NPPES record for Mark O'brien was last updated on September 20, 2019. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 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.