Penny Williams, MD
NPI 1588649453 · Critical Care Medicine (Internal Medicine) Physician · Phoenix, AZ
Enrolled with Medicare as Practitioner - Pulmonary Disease · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Penny Williams, MD is a Critical Care Medicine (Internal Medicine) Physician provider in Phoenix, AZ (NPI 1588649453).
Provider details
- NPI number
- 1588649453
- Entity type
- Individual
- Primary specialty
- Critical Care Medicine (Internal Medicine) PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- 26291 (AZ)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
20 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
4 documented practice locations
- Medicare service volume (vs. specialty peers)28% of score
187 Medicare services, 2024 (ranked within specialty)
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 methodology.
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) |
|---|---|---|
| Critical Care, First 30-74 Minutes99291 | 119 | $201 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 52 | $113 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 16 | $75 |
Typical Medicare-allowed amounts for these services range $75–$201 (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.
Practice location
Mailing address
Additional practice locations (3)
- 2400 S Avenue aYuma, AZ 85364-7127Phone: (928) 344-2000
- 800 W Meeting StLancaster, SC 29720-2202Phone: (843) 792-1414
- 400 N State of Franklin Rd Rm 2746Johnson City, TN 37604-6035Phone: (423) 431-6111
Registry dates
- Enumerated
- 2005-12-13
- Last updated
- 2025-01-28
- Certified
- 2025-01-28
Frequently asked questions
- What is Penny Williams's NPI number?
- Penny Williams's National Provider Identifier (NPI) is 1588649453, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Penny Williams's specialty?
- Penny Williams is listed in the NPPES registry with a primary specialty of Critical Care Medicine (Internal Medicine) Physician (Allopathic & Osteopathic Physicians).
- Where is Penny Williams located?
- Penny Williams's practice location on file with NPPES is 3330 N 2nd St Ste 300, Phoenix, AZ 85012-2369.
- What is Penny Williams's phone number?
- The practice phone number listed in the NPPES registry for Penny Williams is (602) 261-7830.
- Does Penny Williams accept Medicare?
- Penny Williams is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Penny Williams's NPI active?
- Yes — Penny Williams's NPI (1588649453) is active in the NPPES registry as of the last update on 2025-01-28.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.