1. Home
  2. Directory
  3. Colorado
  4. Boulder
  5. Dentist
  6. NPI Profile
Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 30 days.

DR. ETHELYN GAIL THOMASON DMD
NPI 1871585729
Dentist - General Practice in Boulder, CO

Active since August 17, 2005
4155 DARLEY AVE, STE F, BOULDER, CO 80305(303) 499-9700(303) 499-2528 Get Directions Write a Review

NPPES record last updated: July 13, 2026. Verified against the NPPES registry weekly; last sync: July 26, 2026.

About Dr. Ethelyn Gail Thomason Dmd NPPES

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

DR. ETHELYN GAIL THOMASON DMD (NPI 1871585729) is an individual general practice provider in Boulder, Colorado, licensed in Colorado (8399) and active in the NPI registry since August 2005.

NPPES Registry Identity

NPI1871585729
Entity TypeIndividualFemale
Primary Taxonomy1223G0001X
Provider Legal NameDR. ETHELYN GAIL THOMASONCredential: DMD
Location Address4155 DARLEY AVE, STE FBoulder, CO 80305-6536
Mailing Address4155 Darley Ave, Ste FBoulder, CO 80305-6536 · (303) 499-9700 · Fax (303) 499-2528
Phone(303) 499-9700
Fax(303) 499-2528
Sole ProprietorNo
Enumeration DateAugust 17, 2005
Last NPPES UpdateJuly 13, 2026
✔ NPI 1871585729 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyDentist · General PracticeDental Providers
Taxonomy Code1223G0001X
License✔ Licensed in CO · 8399
Definition
A general dentist is the primary dental care provider for patients of all ages. The general dentist is responsible for the diagnosis, treatment, management and overall coordination of services related to patients' oral health needs.
4155 DARLEY AVE, Boulder, CO 80305
Open in Google Maps ↗

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Blue Cross and Blue Shield of Montana, Blue Cross and Blue Shield of Oklahoma, Blue Cross and Blue Shield of Texas and more.Insurance ›

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.

DR. LONNIE M SIBLEY JR. DDS
Dentist (Oral and Maxillofacial Surgery)
4155 DARLEY AVE
BOULDER, CO 80305
Boulder County (303) 499-7072
JOY LIOU HICKS DMD
Dentist (General Practice)
4155 DARLEY AVE, UNIT C
BOULDER, CO 80305
Boulder County (303) 499-7072
EVE LUONG RDH
Dental Hygienist
4155 DARLEY AVE
BOULDER, CO 80305
Boulder County (303) 499-7072
MIROSLAWA GABRIELA HARI R.D.H.
Dental Hygienist
4155 DARLEY AVE
BOULDER, CO 80305
Boulder County (303) 499-7072

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 Ethelyn Thomason's NPI number?

The NPI number for Ethelyn Thomason is 1871585729. It was assigned to this individual provider in the NPPES registry on August 17, 2005.

Where is Ethelyn Thomason located?

Ethelyn Thomason practices at 4155 Darley Ave Ste F, Boulder, CO 80305. The listed phone number is (303) 499-9700.

What is Ethelyn Thomason's specialty?

The primary specialty registered for this NPI is Dentist, specializing in General Practice, with taxonomy code 1223G0001X.

What insurance does Ethelyn Thomason accept?

Health plans from Blue Cross and Blue Shield of Montana, Blue Cross and Blue Shield of Oklahoma, Blue Cross and Blue Shield of Texas, HRI Dental & Vision and Paramount and 1 other insurer list Ethelyn Thomason as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Ethelyn Thomason was last updated on July 13, 2026. NPI Profile syncs with the weekly NPPES data releases published by CMS.