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DOREEN BEST SIELERT LCSW
NPI 1952030207
Social Worker - Clinical in Santa Rosa, CA

Active since June 09, 2022PECOS Enrolled
PO BOX 6927, SANTA ROSA, CA 95406(707) 623-0129 Get Directions Write a Review

NPPES record last updated: January 7, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Jan 7, 2026, Aug 12, 2025, Jun 9, 2022 (3 updates tracked since 2022).

About Doreen Best Sielert Lcsw NPPES

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

DOREEN BEST SIELERT LCSW (NPI 1952030207) is an individual clinical provider in Santa Rosa, California, licensed in California (113022) and active in the NPI registry since June 2022. She is enrolled in Medicare PECOS and maintains a secondary practice location in Santa Rosa.

NPPES Registry Identity

NPI1952030207
Entity TypeIndividualFemale
Primary Taxonomy1041C0700X
Provider Legal NameDOREEN BEST SIELERTCredential: LCSW
Location AddressPO BOX 6927Santa Rosa, CA 95406-0927
Mailing AddressPo Box 6927Santa Rosa, CA 95406-0927 · (707) 623-0129
Phone(707) 623-0129
Sole ProprietorYes
Enumeration DateJune 9, 2022
Last NPPES UpdateJanuary 7, 20263 updates tracked since enumeration
NPPES CertifiedJanuary 7, 2026
✔ NPI 1952030207 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 CA · 113022
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.
PO BOX 6927, Santa Rosa, CA 95406
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Other Names 1

Other Name (5)Doreen Best Sielert Lcsw

Secondary Practice Location 1

Location 1PO Box 6927Santa Rosa, CA 95406-0927 · Phone (707) 623-0129

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Doreen Best Sielert 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 Reassignments

2

Medicare enrollment records show Doreen Sielert reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

County Of Sonoma
2.4 mi
Mental Health (Including Community Mental Health Center)
2225 CHALLENGER WAY
Santa Rosa, CA 95407
  • Reassigned Medicare billing, California enrollment
  • 64 clinicians in this Medicare group
NPI 1154537512 (707) 565-6950
Sutter Bay Medical Foundation
51 mi
Multi-Specialty
12 CAMINO ENCINAS
Orinda, CA 94563
  • Reassigned Medicare billing, California enrollment
  • 4,479 clinicians in this Medicare group
NPI 1366898538 (510) 204-8180

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 95406 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 $63.04 – $187.01
Typical copayment $0.00 (range $15.76 – $46.75)
Most-billed visit code NA
Established Patient
$77.94 typical visit price
range $21.02 – $153.40
Typical copayment $19.48 (range $5.25 – $38.35)
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 Doreen Sielert's NPI number?

The NPI number for Doreen Sielert is 1952030207. It was assigned to this individual provider in the NPPES registry on June 9, 2022. The provider is also known as Doreen Best Sielert Lcsw.

Where is Doreen Sielert located?

Doreen Sielert practices at PO Box 6927, Santa Rosa, CA 95406. The listed phone number is (707) 623-0129.

What is Doreen Sielert's specialty?

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

Is Doreen Sielert enrolled in Medicare?

Yes. Doreen Sielert is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Doreen Sielert's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Doreen Sielert reassigns Medicare benefits to 2 organizations: County Of Sonoma (Santa Rosa, CA) and Sutter Bay Medical Foundation (Orinda, CA). Each 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 Doreen Sielert'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 Doreen Sielert was last updated on January 7, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 months 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.