John Flaherty, MD
NPI 1821028150 · Infectious Disease Physician · Chicago, IL
Enrolled with Medicare as Practitioner - Infectious Disease · source: CMS PECOS Public Provider Enrollment (2026.04.01)
John Flaherty, MD is a Infectious Disease Physician provider in Chicago, IL (NPI 1821028150).
Provider details
- NPI number
- 1821028150
- Entity type
- Individual
- Primary specialty
- Infectious Disease PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 036073534 (IL)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
227 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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 78 | $102 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 69 | $84 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 63 | $140 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 17 | $154 |
Typical Medicare-allowed amounts for these services range $84–$154 (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 · 21 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Dolutegravir Sodium/Lamivudinebrand: Dovato | 115 | 12 |
| Bictegrav/Emtricit/Tenofov Alabrand: Biktarvy | 83 | — |
| Dolutegravir Sodiumbrand: Tivicay | 76 | — |
| Emtricitabine/Tenofov Alafenambrand: Descovy | 71 | — |
| Sulfamethoxazole/Trimethoprimbrand: Sulfamethoxazole-Trimethoprim | 29 | — |
| Elviteg/Cob/Emtri/Tenof Alafenbrand: Genvoya | 29 | — |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-07-03
- Last updated
- 2014-10-02
Frequently asked questions
- What is John Flaherty's NPI number?
- John Flaherty's National Provider Identifier (NPI) is 1821028150, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is John Flaherty's specialty?
- John Flaherty is listed in the NPPES registry with a primary specialty of Infectious Disease Physician (Allopathic & Osteopathic Physicians).
- Where is John Flaherty located?
- John Flaherty's practice location on file with NPPES is 676 N Saint Clair St, Chicago, IL 60611-2927.
- What is John Flaherty's phone number?
- The practice phone number listed in the NPPES registry for John Flaherty is (312) 926-8358.
- Does John Flaherty accept Medicare?
- John Flaherty is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is John Flaherty's NPI active?
- Yes — John Flaherty's NPI (1821028150) is active in the NPPES registry as of the last update on 2014-10-02.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.