Quick answers
- Does William T. Halligan accept Medicare assignment?
- Yes. Medicare's clinician data says William T. Halligan accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does William T. Halligan see?
- In 2024, CMS data shows 1,353 Original Medicare patients and 2,748 services for William T. Halligan. This counts Original Medicare only and measures volume, not quality.
- What is William T. Halligan's NPI number?
- 1255698163. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for William T. Halligan, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 1,353 |
|---|---|
| Services billed to Medicare | 2,748 |
| Different services or procedures | 34 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
Most frequent services
- Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)681 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)642 services
- Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only (93010)250 services
- Ultrasound of heart with color-depicted blood flow, rate, direction and valve function (93306)204 services
- Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)135 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Ischemic heart disease51%
- Arthritis50%
- Chronic kidney disease36%
- Heart failure35%
Hospitals where William T. Halligan works
Medicare's Facility Affiliation Data lists William T. Halligan at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Prisma Health Greenville Memorial HospitalGreenville, SC · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: not listed by Medicare · CCN 420078
- Prisma Health Greer Memorial HospitalGreer, SC · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 420033
- Prisma Health Hillcrest HospitalSimpsonville, SC · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 420037
- Prisma Health Oconee Memorial HospitalSeneca, SC · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 420009
- Prisma Health Patewood HospitalGreenville, SC · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: not listed by Medicare · CCN 420102
Practice locations
Addresses where William T. Halligan is enrolled with Medicare (CMS data updated October 2, 2026).
- 877 W Faris Rd, Suite BGreenville, SC 29605 (864) 455‑6900
Group practices
Medicare enrollment lists William T. Halligan as a member of this group (CMS data updated October 2, 2026).
- Prisma Health University Medical Group2,493 clinicians in the group
Specialties
Find other Cardiovascular Disease (Cardiology) doctors in South Carolina →
Other cardiologists in Greenville
Clinicians with the same Medicare primary specialty in Greenville, SC — not a recommendation.
Other clinicians in Prisma Health University Medical Group
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Medical University Of South Carolina College Of Medicine |
| Graduation year | 2012 (14 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1255698163 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians