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DR. WILLIAM LASSITER HOLMES IV MD
NPI 1063161065
Family Medicine in Houston, TX

Active since March 18, 2022PECOS Enrolled
1100 W 34TH ST, HOUSTON, TX 77018(713) 861-3939 Get Directions Write a Review

NPPES record last updated: January 26, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Dr. William Lassiter Holmes Iv Md NPPES

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

DR. WILLIAM LASSITER HOLMES IV MD (NPI 1063161065) is an individual family medicine provider in Houston, Texas, licensed in Texas (V8283) and active in the NPI registry since March 2022. He is enrolled in Medicare PECOS and is a graduate of Baylor College Of Medicine (2017).

NPPES Registry Identity

NPI1063161065
Entity TypeIndividualMale
Primary Taxonomy207Q00000X
Provider Legal NameDR. WILLIAM LASSITER HOLMES IVCredential: MD
Location Address1100 W 34TH STHouston, TX 77018-6206
Mailing Address1100 W 34th StHouston, TX 77018-6206 · (713) 861-3939
Phone(713) 861-3939
Sole ProprietorNo
Medical School CMSBaylor College Of MedicineGraduated 2017
Enumeration DateMarch 18, 2022
Last NPPES UpdateJanuary 26, 2026
NPPES CertifiedJanuary 26, 2026
✔ NPI 1063161065 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207Q00000X
License✔ Licensed in TX · V8283
Definition
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
1100 W 34TH ST, Houston, TX 77018
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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 (PECOS)

Dr. William Lassiter Holmes Iv Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID2769955103
PECOS Enrollment IDI20260626000266
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 Reassignment

Medicare enrollment records show William Holmes reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Rio Grande Valley Adult & Internal Medicine Specialists PLLC
297 mi
Internal Medicine
1010 JAMES ST
Weslaco, TX 78596
  • Reassigned Medicare billing, Texas enrollment
  • 18 clinicians in this Medicare group
NPI 1528039120 (956) 968-1621

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 77018 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
$90.40 typical visit price
range $58.24 – $176.98
Typical copayment $22.60 (range $14.56 – $44.24)
Most-billed visit code 99203
Established Patient
$102.71 typical visit price
range $18.60 – $143.93
Typical copayment $25.67 (range $4.65 – $35.98)
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.

ERIC WARWICK MD
Family Medicine
1100 W 34TH ST
HOUSTON, TX 77018
Harris County (713) 861-3939
VYAS VENKAT SARABU
Student in an Organized Health Care Education/Training Program
1100 W 34TH ST
HOUSTON, TX 77018
Harris County (713) 861-3939
DR. JOSHUA MINJAE SUH M.D.
Student in an Organized Health Care Education/Training Program
1100 W 34TH ST
HOUSTON, TX 77018
Harris County (713) 861-3939
ADAM CLIFFORD MENDONCA MD
Family Medicine
1100 W 34TH ST
HOUSTON, TX 77018
Harris County (713) 861-3939
JUDY LEVISON MD
Obstetrics & Gynecology
1100 W 34TH ST
HOUSTON, TX 77018
Harris County (713) 861-3939
KHOA V. PHAM M.D.
Family Medicine
1100 W 34TH ST
HOUSTON, TX 77018
Harris County (713) 867-7880
NORTHWEST COMMUNITY HEALTH CLINIC
Clinic/Center (Federally Qualified Health Center (FQHC))
1100 W 34TH ST
HOUSTON, TX 77018
Harris County (713) 861-3939
JUAN ANTONIO GARCIA JR.
Student in an Organized Health Care Education/Training Program
1100 W 34TH ST
HOUSTON, TX 77018
Harris County (713) 861-3939

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 William Holmes's NPI number?

The NPI number for William Holmes is 1063161065. It was assigned to this individual provider in the NPPES registry on March 18, 2022.

Where is William Holmes located?

William Holmes practices at 1100 W 34th St, Houston, TX 77018. The listed phone number is (713) 861-3939.

What is William Holmes's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is William Holmes enrolled in Medicare?

Yes. William Holmes is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for William Holmes's services?

According to the CMS Revalidation Reassignment List (October 2026 release), William Holmes reassigns Medicare benefits to Rio Grande Valley Adult & Internal Medicine Specialists PLLC (Weslaco, TX). The 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 William Holmes'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 William Holmes was last updated on January 26, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 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.