Quick answers
- Does William R. Berrington accept Medicare assignment?
- Yes. Medicare's clinician data says William R. Berrington 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 R. Berrington see?
- In 2024, CMS data shows 156 Original Medicare patients and 555 services for William R. Berrington. This counts Original Medicare only and measures volume, not quality.
- What is William R. Berrington's NPI number?
- 1558374025. 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 R. Berrington, 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 | 156 |
|---|---|
| Services billed to Medicare | 555 |
| Different services or procedures | 8 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes (99233)299 services
- Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)137 services
- Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)76 services
- Critical care, first 30-74 minutes (99291)25 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%
- Arthritis58%
- Ischemic heart disease55%
- Chronic kidney disease51%
- Heart failure51%
Hospitals where William R. Berrington works
Medicare's Facility Affiliation Data lists William R. Berrington 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.
- Swedish IssaquahIssaquah, WA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 500152
- Swedish Medical CenterSeattle, WA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 500027
- Swedish Medical Center / Cherry HillSeattle, WA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 500025
Practice locations
Addresses where William R. Berrington is enrolled with Medicare (CMS data updated October 2, 2026).
- 116 Warren Ave N, Apt 801Seattle, WA 98109
- 6233 51st Ave NESeattle, WA 98115
- 747 BroadwaySeattle, WA 98122 (206) 386‑6000
Group practices
Medicare enrollment lists William R. Berrington as a member of these groups (CMS data updated October 2, 2026).
- Providence Health and Services Oregon1,433 clinicians in the group
- Swedish Health Services1,037 clinicians in the group
- Providence Health and Services Washington475 clinicians in the group
- Providence Medical Institute288 clinicians in the group
Specialties
- Infectious Diseaseprimary
- Internal Medicinealso
Other infectious disease doctors in Seattle
Clinicians with the same Medicare primary specialty in Seattle, WA — not a recommendation.
Other clinicians in Providence Health and Services Oregon
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Alabama School Of Medicine |
| Graduation year | 2000 (26 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1558374025 |
| 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