William Sullivan
NPI 1033177894 · Specialist · Hattiesburg, MS
Enrolled with Medicare as Practitioner - Allergy/Immunology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Sullivan is a Specialist provider in Hattiesburg, MS (NPI 1033177894).
Provider details
- NPI number
- 1033177894
- Entity type
- Individual
- Primary specialty
- SpecialistOther Service Providers
- Sex
- Male
- Sole proprietor
- No
- License
- 12999 (MS)
Specialties & taxonomies
Other Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
14 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 14 | $116 |
Typical Medicare-allowed amounts for these services range $116–$116 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 13 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Montelukast Sodium | 98 | 38 |
| Fluticasone Propionate | 79 | 28 |
| Albuterol Sulfatebrand: Albuterol Sulfate Hfa | 57 | 21 |
| Prednisone | 44 | 31 |
| Azithromycin | 27 | 19 |
| Fluticasone/Umeclidin/Vilanterbrand: Trelegy Ellipta | 26 | — |
| Fluticasone/Vilanterolbrand: Breo Ellipta |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$1,761 across 81 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-05-02
- Last updated
- 2013-05-08
Frequently asked questions
- What is William Sullivan's NPI number?
- William Sullivan's National Provider Identifier (NPI) is 1033177894, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Sullivan's specialty?
- William Sullivan is listed in the NPPES registry with a primary specialty of Specialist (Other Service Providers).
- Where is William Sullivan located?
- William Sullivan's practice location on file with NPPES is 109 Millsaps Dr, Hattiesburg, MS 39402-1348.
- What is William Sullivan's phone number?
- The practice phone number listed in the NPPES registry for William Sullivan is (601) 268-5051.
- Does William Sullivan accept Medicare?
- William Sullivan is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Sullivan's NPI active?
- Yes — William Sullivan's NPI (1033177894) is active in the NPPES registry as of the last update on 2013-05-08.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.