DUNCAN JAMES WILLIAMS DO
NPI 1225730781
Emergency Medicine in Las Vegas, NV

Q: What is Duncan Williams's NPI number?

The NPI number for Duncan Williams is 1225730781. It was assigned to this individual provider in the NPPES registry on March 20, 2023.

Q: What is Duncan Williams's specialty?

The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.

Q: When was this NPI record last updated?

The NPPES record for Duncan Williams was last updated on July 16, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.

Active since March 20, 2023PECOS EnrolledAccepts Medicare Assignment

3186 S MARYLAND PKWY, LAS VEGAS, NV 89109(702) 961-5000 Get Directions Write a Review

NPPES record last updated: July 16, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Jul 16, 2026, Apr 30, 2026, Mar 20, 2023 (3 updates tracked since 2023).

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About Duncan James Williams Do NPPES

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

DUNCAN JAMES WILLIAMS DO (NPI 1225730781) is an individual emergency medicine provider in Las Vegas, Nevada, licensed in Nevada (DO4122) and active in the NPI registry since March 2023. He is enrolled in Medicare PECOS and is a graduate of Arizona College Of Osteopathic Medicine Mid Western University (2023).

NPPES Registry Identity

NPI1225730781

Entity TypeIndividualMale

Primary Taxonomy207P00000X

Provider Legal NameDUNCAN JAMES WILLIAMSCredential: DO

Location Address3186 S MARYLAND PKWYLas Vegas, NV 89109-2306

Mailing Address4637 Chabot Dr Ste 104Pleasanton, CA 94588-2749 · (925) 924-1600

Phone(702) 961-5000

Sole ProprietorYes

Medical School CMSArizona College Of Osteopathic Medicine Mid Western UniversityGraduated 2023

Enumeration DateMarch 20, 2023

Last NPPES UpdateJuly 16, 20263 updates tracked since enumeration

NPPES CertifiedJuly 16, 2026

✔ NPI 1225730781 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyEmergency MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207P00000X

Licenses✔ Licensed in NV · DO4122✔ Licensed in AZ · 012254

Definition

An emergency physician focuses on the immediate decision making and action necessary to prevent death or any further disability both in the pre-hospital setting by directing emergency medical technicians and in the emergency department. The emergency physician provides immediate recognition, evaluation, care, stabilization and disposition of a generally diversified population of adult and pediatric patients in response to acute illness and injury.

3186 S MARYLAND PKWY, Las Vegas, NV 89109

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Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Duncan James Williams Do is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID3274989934

PECOS Enrollment IDI20260515002953

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

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

Fremont Emergency Services Scherr Ltd

0.1 mi

Emergency Medicine

3186 S MARYLAND PKWY
Las Vegas, NV 89109

Reassigned Medicare billing, Nevada enrollment
304 clinicians in this Medicare group

NPI 1518120971 (702) 731-8585

Emergency Physicians Southwest, PC

271 mi

Emergency Medicine

6644 E BAYWOOD AVE
Mesa, AZ 85206

Reassigned Medicare billing, Arizona enrollment
289 clinicians in this Medicare group

NPI 1912053752 (480) 321-2000

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 89109 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

$88.51 typical visit price

range $57.07 – $173.24

Typical copayment $22.12 (range $14.26 – $43.31)

Most-billed visit code 99203

Established Patient

$100.60 typical visit price

range $18.27 – $140.96

Typical copayment $25.15 (range $4.56 – $35.24)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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.

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