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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

MS. TAMMY LYNN MEHLHAFF LCSW
NPI 1801774310
Social Worker - Clinical in Billings, MT

Active since August 22, 2025PECOS Enrolled
1025 S. 25TH ST. W, BILLINGS, MT 59101(406) 272-6590 Get Directions Write a Review

NPPES record last updated: September 2, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Ms. Tammy Lynn Mehlhaff Lcsw NPPES

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

MS. TAMMY LYNN MEHLHAFF LCSW (NPI 1801774310) is an individual clinical provider in Billings, Montana, licensed in Montana (BBH-LCSW-LIC-89866) and active in the NPI registry since August 2025. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1801774310
Entity TypeIndividualFemale
Primary Taxonomy1041C0700X
Provider Legal NameMS. TAMMY LYNN MEHLHAFFCredential: LCSW
Location Address1025 S. 25TH ST. WBillings, MT 59101
Mailing Address744 Wyoming AveBillings, MT 59101-1619 · (406) 545-9077
Phone(406) 272-6590
Sole ProprietorNo
Enumeration DateAugust 22, 2025
Last NPPES UpdateSeptember 2, 2026
NPPES CertifiedSeptember 2, 2026
✔ NPI 1801774310 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtySocial Worker · ClinicalBehavioral Health & Social Service Providers
Taxonomy Code1041C0700X
License✔ Licensed in MT · BBH-LCSW-LIC-89866
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.
1025 S. 25TH ST. W, Billings, MT 59101
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Ms. Tammy Lynn Mehlhaff 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.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 59101 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 $56.81 – $172.26
Typical copayment $0.00 (range $14.20 – $43.06)
Most-billed visit code NA
Established Patient
$70.82 typical visit price
range $18.24 – $140.32
Typical copayment $17.70 (range $4.56 – $35.08)
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 Tammy Mehlhaff's NPI number?

The NPI number for Tammy Mehlhaff is 1801774310. It was assigned to this individual provider in the NPPES registry on August 22, 2025.

Where is Tammy Mehlhaff located?

Tammy Mehlhaff practices at 1025 S. 25th St. W, Billings, MT 59101. The listed phone number is (406) 272-6590.

What is Tammy Mehlhaff's specialty?

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

Is Tammy Mehlhaff enrolled in Medicare?

Yes. Tammy Mehlhaff is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for Tammy Mehlhaff was last updated on September 2, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 53 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.