Gregory W Gerritsen, PHD
Gregory W Gerritsen is a Clinical Psychologist provider (Psychologist) practicing in Boulder, CO, registered in the NPPES registry with NPI 1083795686 since 2006. The credential PHD stands for Doctor of Philosophy.
✓ Active NPI ✓ Valid NPI checksum Sole proprietor
| NPI | 1083795686 |
|---|---|
| Entity type | Individual (Type 1) |
| Name | Gregory W Gerritsen |
| Credential | PHD |
| Sex | Male |
| Practice address | Boulder, CO, 80302 |
| Phone | 3034734433 |
| Fax | 3034992217 |
| Enumeration date | 2006-10-18 |
| Last updated in NPPES | 2007-10-23 |
Street address withheld — NPPES sole-proprietor addresses can be home addresses. See our data policy.
Taxonomy & licenses
| Taxonomy code | Specialty | Primary | License | State |
|---|---|---|---|---|
| 103TC0700X | Clinical Psychologist | Primary | 1209 | CO |
PHD — Doctor of Philosophy: A doctoral degree; in healthcare often held by clinical psychologists and researchers. About the PHD credential
Other identifiers
| Identifier | Type | State | Issuer |
|---|---|---|---|
| 07012099 | Medicaid | CO | — |
Copy-ready billing details
Provider: Gregory Gerritsen, PHD NPI: 1083795686 Taxonomy: 103TC0700X (Clinical Psychologist) Address: Boulder, CO, 80302
Other providers at this practice address
| NPI | Name | Type | Specialty | Location |
|---|---|---|---|---|
| 1568417327 | Arlene Hegg | Individual | Specialist | Boulder, CO |
| 1194772996 | Richard Suddath | Individual | Psychiatry Physician | Boulder, CO |
| 1851330435 | John Kirk | Individual | Specialist | Boulder, CO |
| 1609891779 | Suzanne Sundheim | Individual | Child & Adolescent Psychiatry Physician | Boulder, CO |
| 1457361339 | Suzanne Sundheim MD Professional LLC | Organization | Psychiatry Physician | Boulder, CO |
| 1801943477 | Earle Shugerman | Individual | Psychiatry Physician | Boulder, CO |
| 1508911512 | Lauri Liverman | Individual | Psychiatric/Mental Health Nurse Practitioner | Boulder, CO |
| 1306963277 | Melanie Young | Individual | Clinical Psychologist | Boulder, CO |
Verify this record
Cross-check NPI 1083795686 against the authoritative CMS record: view Gregory W Gerritsen on the official NPPES registry .
What is an NPI number?
A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes — even if the provider moves or changes specialty. Read the full guide or validate an NPI number.
Frequently asked questions
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Source: CMS NPPES (public data). Snapshot 2026-07-11. Provider record last updated 2007-10-23.