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Newly Listed Provider — this NPI profile has been added to the NPI registry within the last 90 days.

DR. MARIELLE KAUALANI ONSTOTT PHD
NPI 1528977436
Counselor - Mental Health in Littleton, CO

Active since September 04, 2026
5554 S PRINCE ST, LITTLETON, CO 80120(303) 730-8858 Get Directions Write a Review

NPPES record added: September 4, 2026. Verified against the NPPES registry weekly; last sync: September 06, 2026.

About Dr. Marielle Kaualani Onstott Phd NPPES

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

DR. MARIELLE KAUALANI ONSTOTT PHD (NPI 1528977436) is an individual mental health provider in Littleton, Colorado and active in the NPI registry since September 2026.

NPPES Registry Identity

NPI1528977436
Entity TypeIndividualFemale
Primary Taxonomy101YM0800X
Provider Legal NameDR. MARIELLE KAUALANI ONSTOTTCredential: PHD
Location Address5554 S PRINCE STLittleton, CO 80120-1149
Mailing Address9231 Travis StThornton, CO 80229-3839 · (720) 477-9642
Phone(303) 730-8858
Sole ProprietorNo
Enumeration DateSeptember 4, 2026
NPPES CertifiedSeptember 4, 2026
✔ NPI 1528977436 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyCounselor · Mental HealthBehavioral Health & Social Service Providers
Taxonomy Code101YM0800X
5554 S PRINCE ST, Littleton, CO 80120
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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.

HEALTH HUNTER, LLC
Social Worker (Clinical)
5554 S PRINCE ST, SUITE 209
LITTLETON, CO 80120
Arapahoe County (303) 374-4665
ELLA MARTIN
Counselor (Professional)
5554 S PRINCE ST
LITTLETON, CO 80120
Arapahoe County (303) 730-8858
LEAH NEAS
Social Worker (Clinical)
5554 S PRINCE ST
LITTLETON, CO 80120
Arapahoe County (303) 730-8858
MRS. MACKENZIE RUTH KRYZER LCSW
Social Worker (Clinical)
5554 S PRINCE ST
LITTLETON, CO 80120
Arapahoe County (303) 730-8858
MISS ASHLEY LYNETTE CASSIDY MA, LPC, LAC
Counselor (Professional)
5554 S PRINCE ST
LITTLETON, CO 80120
Arapahoe County (303) 730-8858
ALISON ENGLER
Counselor (Professional)
5554 S PRINCE ST
LITTLETON, CO 80120
Arapahoe County (303) 730-8858
BRITTAINY JOHNSON
Social Worker (Clinical)
5554 S PRINCE ST
LITTLETON, CO 80120
Arapahoe County (303) 730-8858
ANNIE WHARTON
Social Worker (Clinical)
5554 S PRINCE ST
LITTLETON, CO 80120
Arapahoe County (303) 730-8858

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 Marielle Onstott's NPI number?

The NPI number for Marielle Onstott is 1528977436. It was assigned to this individual provider in the NPPES registry on September 4, 2026.

Where is Marielle Onstott located?

Marielle Onstott practices at 5554 S Prince St, Littleton, CO 80120. The listed phone number is (303) 730-8858.

What is Marielle Onstott's specialty?

The primary specialty registered for this NPI is Counselor, specializing in Mental Health, with taxonomy code 101YM0800X.

When was this NPI record last updated?

The NPPES record for Marielle Onstott was last updated on September 4, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 6 days 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.