Active NPI
William Martin Greenstadt, PH.D.
- Psychoanalysis Psychologist
- New York, NY
National Provider Identifier
1922021559
On this page
Key facts
NPPES NPI Registry- Primary specialty
- Psychoanalysis Psychologist
- License
- 000338-1
- Practice address
- 232 Madison Ave
Suite 1308
New York, NY 10016-2901 - Phone
- (212) 686-9256
- Fax
- (212) 686-4104
- NPI assigned
- Jul 25, 2006
- Sex
- Male
- Sole proprietor
- Yes
NPPES NPI Registry
Registry information is reported by the provider to CMS and is not verified. About this source
Specialties & licenses 2
| Specialty (taxonomy) | Code | License | State | Primary |
|---|---|---|---|---|
| Psychoanalysis Psychologist | 103TP0814X | 000338-1 | NY | Primary |
| Psychologist | 103T00000X | 002936-1 | NY |
Addresses
Primary practice location
232 Madison Ave
Suite 1308
New York, NY 10016-2901
Mailing address
232 Madison Avenue
Suite 1308
New York, NY 10016
Phone (212) 686-9256
Other identifiers 2
| Identifier | Type | State | Issuer |
|---|---|---|---|
| 0001099299 | Other | NY | MHN VENDOR NO. |
| 0097451 | Other | NY | GHI PROVIDER NUMBER |
Medicare participation
Medicare enrollment files- Medicare fee-for-service enrollment
- Not listed in the public Medicare enrollment file
National Provider Directory
National Provider Directory- Medicare enrollment (NPD)
- Enrolled
- Credentials
- Doctor of Philosophy
State licenses
| License | State | Type | Specialty |
|---|---|---|---|
| 000338-1 | NY | MD | Psychoanalysis Psychologist |
| 002936-1 | NY | MD | Occupational Therapy Assistant |
NPI Registry JSON
The complete NPPES record for this NPI in the NPI Registry API format.
{
"created_epoch": "1153785600000",
"enumeration_type": "NPI-1",
"last_updated_epoch": "1757548800000",
"number": "1922021559",
"addresses": [
{
"country_code": "US",
"country_name": "United States",
"address_purpose": "MAILING",
"address_type": "DOM",
"address_1": "232 MADISON AVENUE",
"address_2": "SUITE 1308",
"city": "NEW YORK",
"state": "NY",
"postal_code": "10016",
"telephone_number": "212-686-9256",
"fax_number": "212-686-4104"
},
{
"country_code": "US",
"country_name": "United States",
"address_purpose": "LOCATION",
"address_type": "DOM",
"address_1": "232 MADISON AVE",
"address_2": "SUITE 1308",
"city": "NEW YORK",
"state": "NY",
"postal_code": "100162901",
"telephone_number": "212-686-9256",
"fax_number": "212-686-4104"
}
],
"practiceLocations": [],
"basic": {
"last_name": "GREENSTADT",
"first_name": "WILLIAM",
"middle_name": "MARTIN",
"name_prefix": "Dr.",
"credential": "PH.D.",
"sole_proprietor": "YES",
"sex": "M",
"enumeration_date": "2006-07-25",
"last_updated": "2025-09-11",
"status": "A"
},
"taxonomies": [
{
"code": "103TP0814X",
"taxonomy_group": "",
"desc": "Psychologist, Psychoanalysis",
"state": "NY",
"license": "000338-1",
"primary": true
},
{
"code": "103T00000X",
"taxonomy_group": "",
"desc": "Psychologist",
"state": "NY",
"license": "002936-1",
"primary": false
}
],
"identifiers": [
{
"code": "01",
"desc": "Other (non-Medicare)",
"issuer": "MHN VENDOR NO.",
"identifier": "0001099299",
"state": "NY"
},
{
"code": "01",
"desc": "Other (non-Medicare)",
"issuer": "GHI PROVIDER NUMBER",
"identifier": "0097451",
"state": "NY"
}
],
"endpoints": [],
"other_names": []
}Other providers in New York, NY
Sources for this page
- NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Sep 11, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
- National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.