Quick answers
- Does Andrew S. Greenstone accept Medicare assignment?
- Yes. Medicare's clinician data says Andrew S. Greenstone 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 Andrew S. Greenstone see?
- In 2024, CMS data shows 280 Original Medicare patients and 1,075 services for Andrew S. Greenstone. This counts Original Medicare only and measures volume, not quality.
- What is Andrew S. Greenstone's NPI number?
- 1801817200. 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 Andrew S. Greenstone, 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 | 280 |
|---|---|
| Services billed to Medicare | 1,075 |
| Different services or procedures | 5 |
| Participating Medicare provider | Yes |
| Average age of these patients | 77 |
Most frequent services
- Psychotherapy, 45 minutes (90834)756 services
- Psychiatric diagnostic evaluation (90791)257 services
- Psychotherapy, 30 minutes (90832)37 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%
- Depression75%
- Anxiety73%
- Arthritis62%
- Alzheimer's disease or dementia58%
Practice locations
Addresses where Andrew S. Greenstone is enrolled with Medicare (CMS data updated October 2, 2026).
- 4011 Williams Dr, Suite 800Georgetown, TX 78628 (512) 868‑2700
Group practices
Medicare enrollment lists Andrew S. Greenstone as a member of this group (CMS data updated October 2, 2026).
- Rolling Hills Behavioral Health Services4 clinicians in the group
Specialties
- Clinical Psychologistprimary
Other clinical psychologists in Georgetown
Clinicians with the same Medicare primary specialty in Georgetown, TX — not a recommendation.
Other clinicians in Rolling Hills Behavioral Health Services
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | CP |
|---|---|
| Graduation year | 2001 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1801817200 |
| 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