Quick answers
- Does Marc R. Grossman accept Medicare assignment?
- Yes. Medicare's clinician data says Marc R. Grossman 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 Marc R. Grossman see?
- In 2024, CMS data shows 90 Original Medicare patients and 387 services for Marc R. Grossman. This counts Original Medicare only and measures volume, not quality.
- What is Marc R. Grossman's NPI number?
- 1003904988. 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 Marc R. Grossman, 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 | 90 |
|---|---|
| Services billed to Medicare | 387 |
| Different services or procedures | 9 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
Most frequent services
- Established patient office or other outpatient visit with straightforward medical decision making, if using time, 10 minutes or more (99212)115 services
- Eye training exercise performed by health care professional (92065)105 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)71 services
- Extended exam involving color vision testing (92283)52 services
- Imaging of optic nerve (92133)14 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 cholesterol61%
- Arthritis36%
- High blood pressure31%
- Anxiety21%
- Osteoporosis20%
- Ischemic heart disease19%
Practice locations
Addresses where Marc R. Grossman is enrolled with Medicare (CMS data updated October 2, 2026).
- 20 Chestnut StRye, NY 10580 (914) 967‑1740
Specialties
- Optometryprimary
Other optometrists in Rye
Clinicians with the same Medicare primary specialty in Rye, NY — not a recommendation.
Clinician information
| Credential | OD |
|---|---|
| Optometry school | State University Of New York - State College Optometry |
| Graduation year | 1980 (46 years since optometry school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1003904988 |
| 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
- 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