William G. Matthaeus, MD
Hematology & Oncology Physician · Milwaukee, WI
William G. Matthaeus, MD is a hematology & oncology physician with a practice address in Milwaukee, Wisconsin, and NPI 1326039074, issued on Nov 2, 2005. Check the license (Wisconsin 25992, as entered in NPPES) on the Wisconsin Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- William G. Matthaeus
- Credential
- MD
- Primary taxonomy
- Hematology & Oncology Physician 207RH0003X
- License number
- 25992 WI
Self-reported in NPPES; status is on the state search - Practice location
- 1055 N Mayfair RD, Milwaukee, WI 53226
- Phone
- (262) 857-5750
- Enumerated
- Nov 2, 2005
- Record last updated
- Sep 24, 2024
- Medicaid ID
- 30850600 WI
- Medicare enrollment
- Enrolled (PECOS I20040923000223); accepts Medicare assignment
- Medical or professional school
- Medical College Of Wisconsin, 1983
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest hematology & oncology physician records → All 295 in Wisconsin → Look up another NPI →
Verify William G. Matthaeus in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWisconsin Medical Examining Board
Search for license 25992Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
74% more Medicare Part D claims than the average hematology & oncology physician in 2024
1,523 Medicare Part D claims for 226 beneficiaries, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D. Brand-name drugs were 28% of claims. 124 claims were for opioids.
Most prescribed
- Anastrozole172 claims
- Prochlorperazine Maleate88 claims
- Letrozole84 claims
- Prednisone62 claims
- Eliquis55 claims
- Ibrance55 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
- Aurora Health Care Central, Inc.Sheboygan, WI
- Aurora Health Care Metro, Inc.Milwaukee, WI
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William G. Matthaeus among 295 hematology & oncology physician records in Wisconsin
William G. Matthaeus, MD 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 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 92% newer
- In a Medicare fileYes · 82% of these records are
- In the CMS Doctors and Clinicians fileYes · 74% of these records are
- Graduated1983 · median 2004 among the 217 with a school on file
- Record last updated2024 · 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).
Hematology & Oncology Physician providers in Wisconsin
There are 295 hematology & oncology physician records in Wisconsin.
All 295 in Wisconsin → Every provider in Milwaukee → Hematology & Oncology Physician nationwide →
The 8 hematology & oncology physician records with the nearest ZIP codes
- Yee Chung Cheng, MDMilwaukee, WI 532261811948318
- Christopher Chitambar, MDMilwaukee, WI 532261215987748
- William Drobyski, MDMilwaukee, WI 532261861443848
- Amy Harker-Murray, MDMilwaukee, WI 532261760459663
- Peiman Hematti, MDMilwaukee, WI 532261710953732
- Walter Longo, MDMilwaukee, WI 532261629044649
- Joel Lundberg, MDMilwaukee, WI 532261306827621
- Mark Moskowitz, MDMilwaukee, WI 532261295718815
Common questions
What is William G. Matthaeus, MD's NPI number?
William G. Matthaeus, MD's National Provider Identifier (NPI) is 1326039074, issued on Nov 2, 2005. An NPI identifies a provider in billing; it is not a license.
Where is William G. Matthaeus, MD located?
The NPPES record lists a practice address at 1055 N Mayfair RD, Milwaukee, WI, 53226. Phone: (262) 857-5750. Providers update this record themselves, so call before visiting.
How can I verify William G. Matthaeus, MD's license?
NPPES lists Wisconsin license number 25992, 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 William G. Matthaeus, MD prescribe under Medicare Part D?
In 2024, William G. Matthaeus, MD had 1,523 Medicare Part D claims for 226 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.
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.