NPPES file of Aug 9, 2026

Justin James Chau, M.D.

Hematology & Oncology Physician · Grafton, WI

Justin James Chau, M.D. is a hematology & oncology physician with a practice address in Grafton, Wisconsin, and NPI 1871974154, issued on Jun 12, 2015. Check the license (Wisconsin 82045, as entered in NPPES) on the Wisconsin Medical Examining Board; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1871974154
Name
Justin James Chau
Credential
M.D.
Primary taxonomy
Hematology & Oncology Physician 207RH0003X
License numbers
82045 WI
MD-45076 IA
Self-reported in NPPES; status is on the state search
Practice location
975 Port Washington RD, Grafton, WI 53024
Enumerated
Jun 12, 2015
Record last updated
May 5, 2026
Medicaid ID
100236288 WI
Medicare enrollment
Enrolled (PECOS I20230522000534); accepts Medicare assignment
Medical or professional school
University Of Iowa, Rj & L Carver College Of Medicine, 2015
Telehealth
Offers telehealth (CMS)
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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8 nearest hematology & oncology physician records → All 295 in Wisconsin → Look up another NPI →

Also registered at 975 Port Washington RD

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Hamid Afsari, D.O.Hospitalist Physician1053672048
  2. Muhammed Al-Fawakhiri, MDInternal Medicine Physician1942276613
  3. Beverly Altman, LMTMassage Therapist1447888789
  4. Claudia Altmann, MDInfectious Disease Physician1386691756
  5. Peter Andrew, AAAnesthesiologist Assistant1821704545
  6. Patrick AndrewsPhysical Therapist1689481962

Verify Justin James Chau in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersWisconsin Medical Examining Board
    Search for license 82045    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the Wisconsin license search

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23% fewer Medicare Part D claims than the average hematology & oncology physician in 2024

677 Medicare Part D claims for 107 beneficiaries, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D. 25 claims were for opioids.

  1. Justin Chau677
  2. Specialty average877

Most prescribed

  1. Prednisone92 claims
  2. Abiraterone Acetate52 claims
  3. Anastrozole41 claims
  4. Hydroxyurea41 claims
  5. Eliquis31 claims
  6. Pantoprazole Sodium23 claims

Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.

Bills Medicare through 2 group practices

  1. Aurora Advanced Healthcare, Inc.Grafton, WI
  2. Aurora Health Care Metro, Inc.Grafton, WI

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Justin James Chau among 295 hematology & oncology physician records in Wisconsin

Justin James Chau, M.D. is one of 295 hematology & oncology physician records with a practice address in Wisconsin. 82% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2015, is newer than 81% of them.

  • NPI issued2015 · 81% of these records are older, 14% newer
  • In a Medicare fileYes · 82% of these records are
  • In the CMS Doctors and Clinicians fileYes · 74% of these records are
  • Graduated2015 · median 2004 among the 217 with a school on file
  • Record last updated2026 · 51% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RH0003X and a Wisconsin practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

5 hematology & oncology physician records list a practice address in Grafton

They are 5 of the 459 NPPES records with a practice address in Grafton, and 295 hematology & oncology physician records in Wisconsin.

All 295 in Wisconsin → Every provider in Grafton → Hematology & Oncology Physician nationwide →

The 8 hematology & oncology physician records with the nearest ZIP codes

  1. Maria GeorgenGrafton, WI 530241114488129
  2. John Maul, MDGrafton, WI 530241326014382
  3. Peter Polewski, MDGrafton, WI 530241659784940
  4. Thomas Zukowski, MDGrafton, WI 530241912989260
  5. Jacob Adashek, DOGermantown, WI 530221144780107
  6. Timothy Goggins, M.D.Germantown, WI 530221497890701
  7. Stephen Strother, M.D.Brookfield, WI 530451417063231
  8. Michael Delatorre, M.D.Menomonee Falls, WI 530511831211861

Common questions

What is Justin James Chau, M.D.'s NPI number?

Justin James Chau, M.D.'s National Provider Identifier (NPI) is 1871974154, issued on Jun 12, 2015. An NPI identifies a provider in billing; it is not a license.

Where is Justin James Chau, M.D. located?

The NPPES record lists a practice address at 975 Port Washington RD, Grafton, WI, 53024. Providers update this record themselves, so call before visiting.

How can I verify Justin James Chau, M.D.'s license?

NPPES lists Wisconsin license number 82045, as entered by the provider. Search the Wisconsin Medical Examining Board at https://dsps.wi.gov/Pages/BoardsCouncils/MEB/Default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Justin James Chau, M.D. prescribe under Medicare Part D?

In 2024, Justin James Chau, M.D. had 677 Medicare Part D claims for 107 beneficiaries; the average among hematology & oncology physician prescribers was 877. Part D covers Medicare prescriptions only.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.