William Joseph Mazzella, MD
Hospitalist Physician · Greenville, SC
William Joseph Mazzella, MD is a hospitalist physician with a practice address in Greenville, South Carolina, and NPI 1528158227, issued on Oct 13, 2006. Check the license (South Carolina 35221, as entered in NPPES) on the South Carolina Board of Medical Examiners; the Medicare figures below come from public CMS files.
- Name
- William Joseph Mazzella
- Credential
- MD
- Primary taxonomy
- Hospitalist Physician 208M00000X
- License numbers
- 35221 SC
DR0051332 CO
CV2005119 IN
44676 KY
311477 LA
and 1 more
Self-reported in NPPES; status is on the state search - Practice location
- 701 Grove RD FL 5, Greenville, SC 29605
- Phone
- (864) 455-4411
- Enumerated
- Oct 13, 2006
- Record last updated
- Jan 31, 2023
- Fax
- (864) 455-4480
- Medicaid IDs
- 5900336 NC
N0109A SC
7100184720 KY - Medicare enrollment
- Enrolled (PECOS I20211103001169); accepts Medicare assignment
- Medical or professional school
- University Of North Carolina At Chapel Hill School Of Medicine, 1998
- Entity
- Type 1 · individual
8 nearest hospitalist physician records → All 470 in South Carolina → Look up another NPI →
Also registered at 701 Grove RD FL 5
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Ileen AikenNurse Practitioner1861989147
- Omar Alexander, M.D.Hospitalist Physician1679735047
- Mary Ann AllstonFamily Medicine Physician1104490150
- Grace Anastasio, MDHospitalist Physician1780328898
Verify William Joseph Mazzella in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersSouth Carolina Board of Medical Examiners
Search for license 35221Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
1% fewer Medicare Part D claims than the average hospitalist physician in 2024
515 Medicare Part D claims for 204 beneficiaries, against an average of 521 among the 21,613 providers of this specialty who prescribed in Part D. Brand-name drugs were 20% of claims. 11 claims were for opioids.
Most prescribed
- Jardiance32 claims
- Prednisone30 claims
- Levofloxacin28 claims
- Gabapentin21 claims
- Amlodipine Besylate20 claims
- Rosuvastatin Calcium20 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.
Industry payments in 2024: $12.27
1 payment: food and beverage; the largest payer was Zoll Services LLC (a/k/a Zoll LifeCor Corp). The 7,324 providers of this specialty with any payment received $494.84 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.
Bills Medicare through one group practice
- Prisma Health University Medical GroupGreenville, SC
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William Joseph Mazzella among 470 hospitalist physician records in South Carolina
William Joseph Mazzella, MD is one of 470 hospitalist physician records with a practice address in South Carolina. 93% 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 4% of them.
- NPI issued2006 · 4% of these records are older, 74% newer
- In a Medicare fileYes · 93% of these records are
- In the CMS Doctors and Clinicians fileYes · 87% of these records are
- Graduated1998 · median 2011 among the 409 with a school on file
- Record last updated2023 · 42% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 208M00000X and a South Carolina practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
140 hospitalist physician records list a practice address in Greenville
They are 140 of the 10,264 NPPES records with a practice address in Greenville, and 470 hospitalist physician records in South Carolina.
All 470 in South Carolina → Every provider in Greenville → Hospitalist Physician nationwide →
The 8 hospitalist physician records with the nearest ZIP codes
- Bonnie Barr, M.D.Greenville, SC 296051437108602
- Haritha Boppana, MDGreenville, SC 296051750386454
- Michael Cain, M.D.Greenville, SC 296051922058494
- Robert Cartledge, M.D.Greenville, SC 296051043262561
- Grazyna Charowska, M.D.Greenville, SC 296051992755599
- Steven Connelly, MDGreenville, SC 296051780643981
- John Gemmell, MDGreenville, SC 296051750338679
- Kevin Gilroy, M.D.Greenville, SC 296051679531008
Common questions
What is William Joseph Mazzella, MD's NPI number?
William Joseph Mazzella, MD's National Provider Identifier (NPI) is 1528158227, issued on Oct 13, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William Joseph Mazzella, MD located?
The NPPES record lists a practice address at 701 Grove RD FL 5, Greenville, SC, 29605. Phone: (864) 455-4411. Providers update this record themselves, so call before visiting.
How can I verify William Joseph Mazzella, MD's license?
NPPES lists South Carolina license number 35221, as entered by the provider. Search the South Carolina Board of Medical Examiners at https://verify.llronline.com/LicLookup/Med/Med.aspx?div=22. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does William Joseph Mazzella, MD prescribe under Medicare Part D?
In 2024, William Joseph Mazzella, MD had 515 Medicare Part D claims for 204 beneficiaries; the average among hospitalist physician prescribers was 521. 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.