Quick answers
- Does Terra J. Grandmason accept Medicare assignment?
- Yes. Medicare's clinician data says Terra J. Grandmason 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 Terra J. Grandmason see?
- In 2024, CMS data shows 289 Original Medicare patients and 2,727 services for Terra J. Grandmason. This counts Original Medicare only and measures volume, not quality.
- What is Terra J. Grandmason's NPI number?
- 1235328501. 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 Terra J. Grandmason, 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 | 289 |
|---|---|
| Services billed to Medicare | 2,727 |
| Different services or procedures | 20 |
| Participating Medicare provider | Yes |
| Average age of these patients | 74 |
Most frequent services
- New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)152 services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)130 services
- New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more (99203)58 services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)53 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 pressure68%
- High cholesterol67%
- Arthritis42%
- Diabetes29%
- Anxiety25%
- Chronic kidney disease25%
Hospitals where Terra J. Grandmason works
Medicare's Facility Affiliation Data lists Terra J. Grandmason 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.
- Mason General Hospital & Family of ClinicsShelton, WA · Critical Access Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 501336
- Providence Centralia HospitalCentralia, WA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 500019
- Providence St Peter HospitalOlympia, WA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 500024
- Tacoma General Allenmore HospitalTacoma, WA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 500129
Practice locations
Addresses where Terra J. Grandmason is enrolled with Medicare (CMS data updated October 2, 2026).
- 209 Lilly Rd NE, Suite BOlympia, WA 98506 (360) 413‑8250
Group practices
Medicare enrollment lists Terra J. Grandmason as a member of this group (CMS data updated October 2, 2026).
- Puget Sound Gastroenterology PLLC61 clinicians in the group
Specialties
- Nurse Practitionerprimary
Other nurse practitioners in Olympia
Clinicians with the same Medicare primary specialty in Olympia, WA — not a recommendation.
Other clinicians in Puget Sound Gastroenterology PLLC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | NP |
|---|---|
| Graduation year | 2007 |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1235328501 |
| 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