Mary M. Horowitz, MD
Hematology & Oncology Physician · Milwaukee, WI
Mary M. Horowitz, MD is a hematology & oncology physician with a practice address in Milwaukee, Wisconsin, and NPI 1356392195, issued on May 15, 2006. Check the license (Wisconsin 24175, as entered in NPPES) on the Wisconsin Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- Mary M. Horowitz
- Credential
- MD
- Primary taxonomy
- Hematology & Oncology Physician 207RH0003X
- License number
- 24175 WI
Self-reported in NPPES; status is on the state search - Practice location
- 9200 W Wisconsin Ave, Milwaukee, WI 53226
- Phone
- (414) 805-0700
- Enumerated
- May 15, 2006
- Record last updated
- Jan 25, 2013 (not updated in 13 years: call before relying on the address or phone)
- Fax
- (414) 805-0714
- Medicaid ID
- 1356392195 WI
- Entity
- Type 1 · individual
8 nearest hematology & oncology physician records → All 295 in Wisconsin → Look up another NPI →
Also registered at 9200 W Wisconsin Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Shameem Aadam, RPHPharmacist1760755680
- Abubaker Abdalla, MDHospitalist Physician1194187617
- Sameem Abedin, MDHematology & Oncology Physician1063641157
- Lolia Abibo, M.D.Hospitalist Physician1912359795
- Haisam Abid, MBBSHospitalist Physician1578083184
- Faith Abodunrin, MDHematology & Oncology Physician1437768769
Verify Mary M. Horowitz in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWisconsin Medical Examining Board
Search for license 24175Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Industry payments in 2024: $2,961.28
7 payments; by number, the most common kind was travel and lodging; the largest payer was National Marrow Donor Program. The 8,560 providers of this specialty with any payment received $7,481.41 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Mary M. Horowitz among 295 hematology & oncology physician records in Wisconsin
Mary M. Horowitz, 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 2006, is newer than 8% of them.
- NPI issued2006 · 8% of these records are older, 59% newer
- In a Medicare fileYes · 82% of these records are
- In the CMS Doctors and Clinicians fileNo · 74% of these records are
- Record last updated2013 · 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
- William Matthaeus, MDMilwaukee, WI 532261326039074
Common questions
What is Mary M. Horowitz, MD's NPI number?
Mary M. Horowitz, MD's National Provider Identifier (NPI) is 1356392195, issued on May 15, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Mary M. Horowitz, MD located?
The NPPES record lists a practice address at 9200 W Wisconsin Ave, Milwaukee, WI, 53226. Phone: (414) 805-0700. Providers update this record themselves, so call before visiting.
How can I verify Mary M. Horowitz, MD's license?
NPPES lists Wisconsin license number 24175, 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.
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.