Quick answers
- Does Zachary P. Lamaster accept Medicare assignment?
- Yes. Medicare's clinician data says Zachary P. Lamaster 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 Zachary P. Lamaster see?
- In 2024, CMS data shows 94 Original Medicare patients and 418 services for Zachary P. Lamaster. This counts Original Medicare only and measures volume, not quality.
- What is Zachary P. Lamaster's NPI number?
- 1265667810. 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 Zachary P. Lamaster, 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 | 94 |
|---|---|
| Services billed to Medicare | 418 |
| Different services or procedures | 29 |
| Participating Medicare provider | Yes |
| Average age of these patients | 71 |
Most frequent services
- Insertion of needle into vein for collection of blood sample (36415)66 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)55 services
- Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)34 services
- Admn sarscov2 vacc 1 dose (90480)30 services
- Sarscov2 vac 50 mcg/0.5ml im (91322)30 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 cholesterol69%
- High blood pressure64%
- Arthritis34%
- Diabetes31%
- Anxiety26%
- Depression23%
Hospitals where Zachary P. Lamaster works
Medicare's Facility Affiliation Data lists Zachary P. Lamaster 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.
- Advocate Illinois Masonic Medical CenterChicago, IL · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 140182
Practice locations
Addresses where Zachary P. Lamaster is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 6; the Medicare profile lists all.
- 214 McHenry RdBuffalo Grove, IL 60089 (847) 459‑1160
- 3936 N Milwaukee AveChicago, IL 60641 (773) 736‑6125
- 4600 N Ravenswood AveChicago, IL 60640 (773) 561‑7500
- 4600 N Ravenswood Ave, Fl 2Chicago, IL 60640 (773) 561‑7500
- 836 W Wellington, Suite G346Chicago, IL 60657 (773) 296‑7147
Group practices
Medicare enrollment lists Zachary P. Lamaster as a member of this group (CMS data updated October 2, 2026).
- Advocate Health and Hospitals Corporation3,118 clinicians in the group
Specialties
- Family Practiceprimary
Other family doctors in Buffalo Grove
Clinicians with the same Medicare primary specialty in Buffalo Grove, IL — not a recommendation.
Other clinicians in Advocate Health and Hospitals Corporation
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | DO |
|---|---|
| Medical school | Midwestern University, Chicago College Of Osteopathic Med |
| Graduation year | 2009 (17 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1265667810 |
| 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