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DR. DONALD L WILLIAMS M.D.
NPI 1326043266
Internal Medicine in Whitewater, WI

Active since June 16, 2005PECOS Enrolled
1461 W MAIN ST STE B, WHITEWATER, WI 53190(262) 472-6839(262) 472-6839 Get Directions Write a Review

NPPES record last updated: May 28, 2024. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Dr. Donald L Williams M.d. NPPES

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

DR. DONALD L WILLIAMS M.D. (NPI 1326043266) is an individual internal medicine provider in Whitewater, Wisconsin, licensed in Wisconsin (23304) and active in the NPI registry since June 2005. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1326043266
Entity TypeIndividualMale
Primary Taxonomy207R00000X
Provider Legal NameDR. DONALD L WILLIAMSCredential: M.D.
Location Address1461 W MAIN ST STE BWhitewater, WI 53190-1568
Mailing Address1461 W Main St Ste BWhitewater, WI 53190-1568 · (262) 472-6839 · Fax (262) 472-6802
Phone(262) 472-6839
Fax(262) 472-6839
Sole ProprietorNo
Enumeration DateJune 16, 2005
Last NPPES UpdateMay 28, 2024
NPPES CertifiedMay 28, 2024
✔ NPI 1326043266 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in WI · 23304
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
1461 W MAIN ST STE B, Whitewater, WI 53190
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Other Identifiers 1

Medicaid30338400WI

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Anthem Blue Cross and Blue Shield, CareSource (Common Ground Healthcare), Dean Health Plan and more.Insurance ›

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Donald L Williams M.d. 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 Donald Williams reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Rock River Community Clinic Inc
Same address
Federally Qualified Health Center (FQHC)
1461 W MAIN ST STE B
Whitewater, WI 53190
  • Reassigned Medicare billing, Wisconsin enrollment
  • 5 clinicians in this Medicare group
NPI 1184220659 (262) 472-6839
Fort Healthcare Inc
7.3 mi
Rural Health
611 SHERMAN AVE E
Fort Atkinson, WI 53538
  • Reassigned Medicare billing, Wisconsin enrollment
  • 298 clinicians in this Medicare group
NPI 1417450115 (920) 563-5571

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 53190 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
$123.69 typical visit price
range $53.90 – $163.24
Typical copayment $30.92 (range $13.47 – $40.81)
Most-billed visit code 99204
Established Patient
$95.41 typical visit price
range $17.40 – $133.76
Typical copayment $23.85 (range $4.35 – $33.44)
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 2

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

ROCK RIVER COMMUNITY CLINIC INC
Clinic/Center (Federally Qualified Health Center (FQHC))
1461 W MAIN ST STE B
WHITEWATER, WI 53190
Walworth County (262) 472-6839
MS. ELIZABETH MARIE LUCHT MSSW, PA-C
Physician Assistant
1461 W MAIN ST STE B
WHITEWATER, WI 53190
Walworth County (262) 472-6839

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 Donald Williams's NPI number?

The NPI number for Donald Williams is 1326043266. It was assigned to this individual provider in the NPPES registry on June 16, 2005.

Where is Donald Williams located?

Donald Williams practices at 1461 W Main St Ste B, Whitewater, WI 53190. The listed phone number is (262) 472-6839.

What is Donald Williams's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Donald Williams enrolled in Medicare?

Yes. Donald Williams is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Donald Williams's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Donald Williams reassigns Medicare benefits to 2 organizations: Rock River Community Clinic Inc (Whitewater, WI) and Fort Healthcare Inc (Fort Atkinson, WI). 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 Donald Williams's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Donald Williams accept?

Health plans from Anthem Blue Cross and Blue Shield, CareSource (Common Ground Healthcare), Dean Health Plan, Group Health Cooperative-SCW and Quartz list Donald Williams 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 Donald Williams was last updated on May 28, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 years 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.