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THALIA GUILLEN ACSW
NPI 1851063697
Counselor - Mental Health in Merced, CA

Active since September 30, 2021

NPPES record last updated: November 19, 2025. Verified against the NPPES registry weekly; last sync: July 26, 2026.

Record update history: Nov 19, 2025, Sep 19, 2024, Jul 29, 2024 and 3 more (6 updates tracked since 2021).

About Thalia Guillen Acsw NPPES

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

THALIA GUILLEN ACSW (NPI 1851063697) is an individual mental health provider in Merced, California, licensed in California (103266) and active in the NPI registry since September 2021. She maintains 9 additional practice locations.

NPPES Registry Identity

NPI1851063697
Entity TypeIndividualFemale
Primary Taxonomy101YM0800X
Provider Legal NameTHALIA GUILLENCredential: ACSW
Location Address1640 N STMerced, CA 95340-4657
Mailing Address1640 N StMerced, CA 95340-4657 · (209) 381-4547
Phone(209) 381-4547
Sole ProprietorNo
Enumeration DateSeptember 30, 2021
Last NPPES UpdateNovember 19, 20256 updates tracked since enumeration
NPPES CertifiedNovember 19, 2025
✔ NPI 1851063697 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyCounselor · Mental HealthBehavioral Health & Social Service Providers
Taxonomy Code101YM0800X
License✔ Licensed in CA · 103266
1640 N ST, Merced, CA 95340
Open in Google Maps ↗

Secondary Practice Locations 9

Location 19722 Haskell AvenuePlanada, CA 95365 · Phone (209) 382-0756
Location 29525 E. Broderick StreetPlanada, CA 95365 · Phone (209) 382-0272
Location 36300 Cypress AveWinton, CA 95388-9547 · Phone (209) 357-6189
Location 46981 Chestnut LaneWinton, CA 95388 · Phone (209) 357-6891
Location 57265 Almond AveWinton, CA 95388-9325 · Phone (209) 357-6180
Location 613071 E. Le Grand RoadLe Grand, CA 95333 · Phone (209) 389-4515
Location 77160 W. Walnut AvenueWinton, CA 95388 · Phone (209) 357-6182
Location 8161 S. Plainsburg RoadPlanada, CA 95365 · Phone (209) 382-0768
Location 97000 N. Center StreetWinton, CA 95388-9399 · Phone (209) 357-6175

Other Providers at the Same Location NPPES 2

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

NAI SAECHAO
Social Worker (Clinical)
1640 N ST
MERCED, CA 95340
Merced County (209) 381-4533
LETICIA CORREA
Social Worker (Clinical)
1640 N ST
MERCED, CA 95340
Merced County (209) 381-4527

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 Thalia Guillen's NPI number?

The NPI number for Thalia Guillen is 1851063697. It was assigned to this individual provider in the NPPES registry on September 30, 2021.

Where is Thalia Guillen located?

Thalia Guillen practices at 1640 N St, Merced, CA 95340. The listed phone number is (209) 381-4547.

What is Thalia Guillen'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 Thalia Guillen was last updated on November 19, 2025. NPI Profile syncs with the weekly NPPES data releases published by CMS.